Mercury Optimax compressor failure - Got pics of the bearing just about to fail.

[Mr. Demeanor]

This is my THIRD compressor failure in about 450 hours.
The first and second failed running Merc oils (Premium Plus and Opti oil respectively).
The third has been run on Pennzoil XLF since new and has lasted the longest (about 200 hours).
I AM AT MY WITS END AND OUT OF MONEY!!!
This time I noticed a little play in the pulley and decided to pull the to off the compressor and check things out. I found the journal on the big end of the connecting rod starting to fail. Probably caught this JUST in time. Last one completely failed and took out 3 air injectors.
So now we finally have pics of what fails in these things just before it destroys itself leaving no evidence. There is NO sign of heat, discoloration, and very well oiled. This simply looks like metal failure to me but I would like to hear your opinions.
I honestly just cant keep dropping compressors on this thing and not be able to trust a motor I fish 60 miles offshore with now and then.
The rebuild kit and top cap assembly are NLA on Mercs parts list. Do have a new part number for the compressor for about the 50th time.
If there is anyone that has a connect at Merc that might be able to help me out, I sure would appreciate it. I'm not crying poor but just cannot stomach replacing these things at my expense any more when its clearly a defect in workmanship.

Heres the pics:
http://img.photobucket.com/albums/v399/MrDemeanor/Boating/PICT0011-1.jpg

http://img.photobucket.com/albums/v399/MrDemeanor/Boating/PICT0012-1.jpg

http://img.photobucket.com/albums/v399/MrDemeanor/Boating/PICT0013.jpg

http://img.photobucket.com/albums/v399/MrDemeanor/Boating/PICT0014.jpg

http://img.photobucket.com/albums/v399/MrDemeanor/Boating/PICT0016.jpg

[Mr. Demeanor]

It looks like I can rebuild the compressor for about $200.
Looks like I will need:
Top cap assembly.
Connecting rod assembly.
Wrist pin clips.
New oil line filters.

Anything else? Ayone know if I can get the connecting rod out through the bottom or do I have to pull the head and piston out?

If anyone has any ideas on why I am going through compressors every 150 hours I am all ears! I do everything I am suposed to plus I manually pre-oil the new ones and put the computer into break-in mode. The boat is propped right (not that it should effect the compressor) and well maintained. Oil type doesnt seems to matter. Never had an overheat and water flow is great. I clean the screen in the water supply to the compressor annually and just did finding it clear. Oil pooled in the bottom of the compressor is clean. Belt tensioner is working properly.
I am at a loss :confused:

[Euroski]

That looks more like a defect(void) in the casting.

[baddjonny]

Have you tried any of the crankshaft rebuilders they might have a new type crank repair a quick spray weld grind and polish it might be a harder repair than the original surface.
might be worth a try ??
jon b

[Mr. Demeanor]

Have you tried any of the crankshaft rebuilders they might have a new type crank repair a quick spray weld grind and polish it might be a harder repair than the original surface.
might be worth a try ??
jon b

I did consider that and also will be contacting Mercury. At this point I really feel I deserve some support from Mercury.

[merctech5591]

if you get no support from merc, im sure i have a few cranks for an air comp. under my bench. mine just failed this past thanksgiving getting to the dock.

[Mr. Demeanor]

I wonder if I have a bad pulley (out of balance) ? I think the XS motors use a different pulley that might be lighter for higher rpm use. That might be a good upgrade to take some load off the bearings.

[NitroMusky]

Im not an expert on the optis, (but have spent enough time under the cowl fighting demons on mine).... Based on the journal AND scoring on the cylinder I would suspect lube issue getting oil to the compressor. i know you said "well oiled" but how do you know this? have you looked into the the oil flow from the motor to the compressor? I can't believe you had such bad luck as to get 3 bad compressors so i would be looking for some restriction outside of the compressor itself which is causing under lubrication. Best of luck...these motors are great... when they're running right.

[Mr. Demeanor]

I am open to any and all suggestions. I did test oil flow with a DDT last time and will do that again.
I think the light scoring could result from the metal that came off the journal circulating aorund the compressor. Hard to know for sure.

Would be overpropped have any effect on the load on the compressor? I am not overpropped but my boat is big for a single and slow to plane especially when loaded for a big fishing trip. It feels/sounds overpropped but will touch the limiter when its light. Its one of those hulls that just loosens up and runs well over 40mph but feels a little underpowered at slower speeds and when planing off.

[Mr. Demeanor]

Just spent some time checking further. Oil supply hose to compressor and all connections look good. No pinches, no leaks, etc. I put the engine into break-in mode manually and watched oil pump into compressor. There is no measurement listed for the amount pumping into the compressor in the shop manual but flow was there unristricted.
Inspected pulley and it apprears to be true. Inspected belt tensioner which appears to be fine.
I will have a DDT on it this week and test the overall oil output but I really dont think that is it. I can see it getting oil. It looks to me like an issue where the large roller bearing in the top cap assembly can not support the side load placed on the pulley by the belt. The question is why is mine creating a larger side load or why is the bearing unable to support it?
I need to see if there has been an update to the belt tensioner part number. Maybe they have changes the amount of tension? It is a simple spring loaded tensioner with no provision for adjustment but maybe Merc has an update.

Really hoping to find something definite so I can have some faith in the new parts.

[NitroMusky]

Hmm...are you checking the oil output at wot or only at idle? I dont know if is supposed to get more oil at higher rpms or steady amt regardless of speed but a restriction may not manifest itself at low flows, rather acting like a governor to limit the peak of flow.

Lugging the motor (overpropped) shouldn't affect it. Unlike the main pistons which have added stress from extra pressure in the combustion chamber when lugged, the air compressor is not tied into these pistons directly nor does it have pressure being applied to it. it is creating the pressure. Now if there is a problem in that it is allowing a pressure that is too high, I imagine this in theory could stress that piston similar to lugging the motor pistons. I imagine it's running ok when the compressor is working, but you may want to check the air/fuel pressure using a dual gauge to make sure the pressure regulator and tracker valve are good, just to be safe but doubt that's the issue.

More importantly, if youre saying you haven't replaced the top end on the compressor and instead had been rebuilding it, you can't rule that out. Sorry if I didn't catch that the first go around.

[Mr. Demeanor]

More importantly, if youre saying you haven't replaced the top end on the compressor and instead had been rebuilding it, you can't rule that out. Sorry if I didn't catch that the first go around.


I have been replacing the entire compressor with a new factory unit. No rebuilds.
There is no way to check the oil output other than measuring the amount used during the prime sequence.

Here are a couple more pics.
These are pics trying to show the fine metalic particals coming from the bearing in the top cap. This is a large bearing similar to a wheel bearing. Turning it by hand it feels ok but maybe a little stiff. I will have a better comparison when I have the new one to compare to.
http://img.photobucket.com/albums/v399/MrDemeanor/Boating/PICT0017.jpg
http://img.photobucket.com/albums/v399/MrDemeanor/Boating/PICT0016-1.jpg

Pic of the inside of the compressor. You can see it is well oiled. The return oil passages (9 oclock position) are full of metal from the little crank pin.

http://img.photobucket.com/albums/v399/MrDemeanor/Boating/PICT0020.jpg

Pics of the large bearing that has has the crank on one end and the pulley on the other. This is the one that has developed some slop and allowed the crank pin to get out of alignment with the con rod bearing. It has a plastic cover over the rollers to hold oil in the assembly.

http://img.photobucket.com/albums/v399/MrDemeanor/Boating/PICT0021.jpg

Rod bearing that fits over the pitted pin. Looks pretty good considering...

http://img.photobucket.com/albums/v399/MrDemeanor/Boating/PICT0024.jpg

Damn! If it would just come back a little further I could pull the con rod without pulling the head off. Not that its a big deal and I can inspect the reeds at that time.

http://img.photobucket.com/albums/v399/MrDemeanor/Boating/PICT0023.jpg

The problem? I would like to think so but ultimatley, Merc designed it and is responsible for making sure it works.

http://img.photobucket.com/albums/v399/MrDemeanor/Boating/PICT0022.jpg

[NitroMusky]

Ya got me...just tryin to provide some potential areas to explore, as remote as they may be.

If you think they are all failing on account of issues wiht the top bearing then it wouldn't hurt to get a new tensioner as you suggest, if nothing else than for (some?) peace of mind. I seem to recall they are relatively low $, though I also seem to recall that when they fail they tend to lose tension. Any rubber shavings (dust) on top of the motor? Too much can signal problems with the belt system

[Mr. Demeanor]

I just got off the telephone with Matt Cooley at Mercury Marine. Matt tells me that the new compressor has been completely redesigned. The new compressor has a crank assembly that runs completely though the compressor housing with a bearing at each end. This makes a lot of sense and is a welcome change that will hopefully eliminate these failures. Thats the good news.

The bad news is after $3000 in compressor repairs in 500 hours and Matt fully admitting there is a problem with the compressor design that took 11 years to address, they will not help me out financially in any way. I even asked if they would just sell me one at cost. No handouts but a nice gesture that would go along way toward showing some customer appreciation. Matt said he could not do anything because the engine is a 2003. Doesn't matter that the compressor is a 2008.....

So thats it in a nutshell. They MAY have finally fixed the problem. I will be out another $700 in parts and will never own another Mercury product. I will look for a company that values their customers and can see past a few bucks to retain a future customer.

I will post pics and my assessment of the new part when I locate one.



This thread has been forwarded to Matt and I hope he pays particular attention to the number of views it gets.

[Euroski]

If that part was on a car or truck engine there would be a mandated federal recall along with a class action law suit!

[4Speed]

I dont know if this is even possible on this type of compressor but is there a way to measure compressor dischard pressure (CDP) and possibly mount a pressure gage on the dash. I know with gas turbines and shop compressors CDP is very critical and can tell you a lot pertaining to compressor condition. Of couse you are comparing a 1 stage piston to a multi stage axial... Just a thought

[Capt.Insane-o]

Compressor output is rarely a problem unless they self digest themselves. By then they make so much noise or shear the bolts off the pulley it's pretty obvious.

[Mr. Demeanor]

This is just a side load problem in the bearing. They said there is only one bearing in that top cap. I assumed there were two to give the shaft some stability. I will press it apart and post what I find after Christmas.

[Baja 252]

I would talk to Don Weed at European Marine. http://www.europeanmarine.org/

He's one of the best Opti guys around and the Moderator of the 3 liter Merc forum on BBC.
http://www.bbcboards.net/zeroforum?id=227

I'm sure he can shed some light on your problem.

[rustnrot]

That's a shame that they won't sell it to you at cost...they "lose" nothing if they do this and "gain" a lot. Oh well, the bureaucracy always wins.

[XstreamVking]

On my optis, I have a switch for my temp ga.that allows me to either monitor compressor temp, or check the cyl . head temp on the block. When the cooling screen gets clogged the compressor will get hot quick..Can't be good for it.. Going deep into the everglades it gives me come peace of mind anyway.... Has alerted me to crap clogging the screen by an increase in comp temp. Always did this on my old go fast motors for port and stbd head temps... Might help.....

[Mr. Demeanor]

I would talk to Don Weed at European Marine. http://www.europeanmarine.org/

He's one of the best Opti guys around and the Moderator of the 3 liter Merc forum on BBC.
http://www.bbcboards.net/zeroforum?id=227

I'm sure he can shed some light on your problem.

Just spoke with Don. VERY knowledgeable guy. Thanks.
He gave me some ideas and things to look at. Compressors create moisture and he recommends a little squirt of Merc storgae oil in the compressor intake line at the top of the compressor if its going to sit for awhile. The compressor is a steel bore and I boat in a salt/humid envoirnment.
I will wrap this up when I get the new compressor and get it all fixed.

[Euroski]

My 300xs and I'm going to pull it apart next spring to check things out. An idea I have... why not install a filter for when the compressor fails to catch the crap before it gets to the air injectors?? Since the pressure is only about 100lbs a metal case fuel filter should do well? What do you all think?

[Mr. Demeanor]

I pulled the head off my compressor today and the reeds were full of a very fine metalic sludge. Almost like anti-seize grease. It must be a combination of metal that got past the rings and oil. A filter of some sort sounds like a great idea. I also think changing the oil drain lines to clear would let you see the metal in the lines and give you some warning.

[Kimmerly.performance]

My 300xs and I'm going to pull it apart next spring to check things out. An idea I have... why not install a filter for when the compressor fails to catch the crap before it gets to the air injectors?? Since the pressure is only about 100lbs a metal case fuel filter should do well? What do you all think?

http://www.balstonfilters.com/compressed_air_filters.html

Something along the likes of this??? I'm sure you could find a little brass screen that isn't so bulky.

[rustnrot]

To be clear in my mind, "and the reeds were full of a very fine metalic sludge" means that all this crap ends up blowing through the air injectors and on into the engine cylinder, correct?? It is when the compressor really blows up that the metal particles are large enough to plug (and thus ruin) the air injectors, correct?? Finally, have you noticed any abnormal cylinder wear due to all this stuff going in the engine cylinders all these years??

[Mr. Demeanor]

To be clear in my mind, "and the reeds were full of a very fine metalic sludge" means that all this crap ends up blowing through the air injectors and on into the engine cylinder, correct?? It is when the compressor really blows up that the metal particles are large enough to plug (and thus ruin) the air injectors, correct?? Finally, have you noticed any abnormal cylinder wear due to all this stuff going in the engine cylinders all these years??


I should have been mor clear. There is reed valve in the head of the compressor. That is the reed valve that was full of debris.

[pwrman]

Hi what year and model is the motor? the early optimax had compressor issues.

pwr

[mrcrsr]

i found too that customers who do alot of lo speed running/trolling tend to go thru compressors more often, maybe do to the compressor receiving less oil at lo speed operation

[Mr. Demeanor]

Mine is a 2003 which is not one of the early ones known to have failres. The compressors have been 2003, 2005, 2008, and 2011 :eek:
I rarely troll or go wide open. Usually cruising to the fishing grounds 3500-4000rpm, shut down, fish, move on.
I have my fingers crossed this new compressor design is a permanent fix.

[pwrman]

Mine is a 2003 which is not one of the early ones known to have failres. The compressors have been 2003, 2005, 2008, and 2011 :eek:
I rarely troll or go wide open. Usually cruising to the fishing grounds 3500-4000rpm, shut down, fish, move on.
I have my fingers crossed this new compressor design is a permanent fix.

That's sad Merc should step up to plate and fix your motor.
Based on the above, I would not bolt on anther compressor without measuring the runout of the compressor pully and checking the tensioner.

what Hp is the motor and were the fuel rails/injectors service when changing the compressor?

pwr

[rustnrot]

Any update to this? I have a failed Tohatsu TLDI compressor that is of similar (only one bearing on one side of crank) that has failed. I'll start another thread on the failure mode with pictures.

[hydrostream1]

I think the filter in the air pressure line to the compressor is a good idea,someone on here already posted about this.You may have to change it often,guess depends on how much debris gets in the filter.

[Stitch King]

That looks more like a defect(void) in the casting.

That's exactly what it is.

These photo's need to go on every boating site in the world.

How that got past quality controls (Casting, Machining and Assembly) is amazing. Hopefully that part was made in a "Low Cost Country" and not here in the U.S.

[Wayne Cammidge]

I am still waiting to see one of the new design compressors and yet we are still having failures

[powerabout]

how about a paxton, you know where to put the spare air?
how reliable is the compressor on a truck?
class action should get it fixed

[RustyJ671]

Subscribed. A friend of mine is getting a 2014 version of a 300XS. He is being told that that it puts out an additional 17 hp due to the compressor upgrade. I think someone is feeding him a line of crap, but I have yet to find anything stating otherwise. If anyone has any real info, please post it.

[Euroski]

If it makes 17hp with the new pump then I'm changing mine(2007 300xs)!

[native2]

I don't believe it.... But I wouldn't know...

[Liberator*21]

Being a Manufacturing Engineer, I know what I see here. I totally agree with Stitch King, factory defect. That area is a raw casting, no material there from the beginning to machine.........

http://i177.photobucket.com/albums/w201/90profx/1-Junk%20Pics/Casting_zpsdaa20f51.jpg~original (http://s177.photobucket.com/user/90profx/media/1-Junk%20Pics/Casting_zpsdaa20f51.jpg.html)

[LaveyT]

+1 , If it were not for cost savings no body would use castings. Many times we have to shift all of our machining one way or another in an attempt to get the casting to "Clean up". Its always an issue , core shift, worn tooling low paid low skilled employees.:nonod:

[Kcraft]

If it makes 17hp with the new pump then I'm changing mine(2007 300xs)!
What would this new compressor be worth too you for possible 17 HP:D ? Just the peace of mind that is not going to let go would be worth what ever the cost of this new compressor.http://i962.photobucket.com/albums/ae108/KENLARUE/IMG_1404.jpg (http://s962.photobucket.com/user/KENLARUE/media/IMG_1404.jpg.html)

[powerabout]

Being a Manufacturing Engineer, I know what I see here. I totally agree with Stitch King, factory defect. That area is a raw casting, no material there from the beginning to machine.........

http://i177.photobucket.com/albums/w201/90profx/1-Junk%20Pics/Casting_zpsdaa20f51.jpg~original (http://s177.photobucket.com/user/90profx/media/1-Junk%20Pics/Casting_zpsdaa20f51.jpg.html)
Its the Rolls Royce version, damn we machined it wrong, yer but know-one will notice coz its inside the engine....
$10 part - compensation to Qantas $95 million

[half fast]

No ,that was a slick surface.It has been hammered off by the rod bearing.I have seen it many times on outboard cranks.We have seen a great improvment on the new style opti compressor.The new one is now painted black . hf...

[Stitch King]

Gary if you don't take this one, I guess I will....

HF,

Based on your statement two engineers (one with over 30 years and the other with over 20 years of manufacturing experience) from "Americas Biggest Industrial Company" (Fortune Magazine) which is ranked #8 on the Fortune 500 don't know what a bad casting looks like.

There is absolutely no way the void shown above in the machined surface was caused by a mechanical failure.

While I'm sure there are many failures in the field where the bearing and/or rod chewed up the journal, this particular situation is a bad casting which would be the root cause of a bearing failure down the road.

Respectfully,

Ken Wolkens

[ridgerunner]

I agree with Gary, and I have no credentials other than having a weak mind and I can and have been turning wrenches on my own junk. No marks in the unmachined rod journal so there was not enough casting there to machine it smooth. The owner of the compressor took the picture before the thing puked so I don't think your correct half fast. I never seen a bearing failure on a rod make casting marks.
IMO, Chris unearthed the exact cause of compressor failure, quality control. Aside from it being a crappy design in the first place..ie. only one crank bearing on one side of the rod. So far I have had three Opti's without a compressor failure. I run the crap out of them in my slow boat trying to keep the S&F crowd in sight..

Compressors on a truck? Semi-tractor has a good one, not turning as many RPM as the Merc. Tons heavier, lubricated with engine oil and lots larger. Still, maybe Mercury should look to that manufacturer to make their compressors.

The crazy thing is this thread will be at the top of the list here (as it has been) for the compressor failure rate that to me seems unusually high. Mercury has all but denied a problem even exists,(the water sucking problem at high speed too) and I would still buy another one tomorrow despite the troubles. Why should/would Mercury do anything? I am loyal enough so technically I am my own worst enemy.
Who you gonna go with? I like my Mexican made Merc. The E-tec don't fit the harness and the Japanese 2-strokes are slow and dwindling. Just keep the post up top so the E-tec guys can have some decent ammunition to go along with their displacement advantage.:eek: You guys can beat each other up with credentials all day. Merc isn't gonna do bupkiss to help the thousands of compressor failures worldwide.

[LaveyT]

280273 This part has never been close to a bearing or an outboard for that matter. Its Non-Cleanup.

[1BadAction]

280273 This part has never been close to a bearing or an outboard for that matter. Its Non-Cleanup.

I can see that even the outer surface is off quite a bit, and if I can see it with my eyes, I can only imagine how far out it is when you stick a mic on it. :nonod:

[Bies]

Sorry to hear the horror stories, maybe a dumb question, what is the compressor doing, packing the crankcsae?

[RustyJ671]

The compressor provides the air for the direct injectors.

[Bies]

Thank you

[Liberator*21]

Gary if you don't take this one, I guess I will....

HF,

Based on your statement two engineers (one with over 30 years and the other with over 20 years of manufacturing experience) from "Americas Biggest Industrial Company" (Fortune Magazine) which is ranked #8 on the Fortune 500 don't know what a bad casting looks like.

There is absolutely no way the void shown above in the machined surface was caused by a mechanical failure.

While I'm sure there are many failures in the field where the bearing and/or rod chewed up the journal, this particular situation is a bad casting which would be the root cause of a bearing failure down the road.

Respectfully,

Ken Wolkens

Thanks Ken, I stand with your opinion as well. I lived the life of diagnosing engine bearing failures on Jet Engines for GE Aviation and I've seen them all, and even some investment castings used in some mechanical controls when machined off center show the exact same scenario. Any hammering would "NOT" produce a dimpled symmetrical surface finish as shown in the photos, hammering produces impact zone compression layers and given the fact there's absolutely evidence of hammering it is a cast surface. That's my story and I'm stick'n to it...........

[half fast]

He said it lasted 200 hrs.If in fact it was like that from the begining it would have made it maybe 20 minutes.When the heat treated outer surface goes that is exactly what it looks like on any outboard crank. hf... Don't really care if he is fortune 500 or not .How many outboards or optis has he worked on ?

[Liberator*21]

Don't really care if he is fortune 500 or not .How many outboards or optis has he worked on ?

No disrespect intended hf, but between Ken and I, we've both seen our share of the internal workings of Merc motors. We've both built and rebuilt quite a few motors, so it's not like we're voicing an opinion without prior experience. I respect your opinion as well, but without any of us having the actual failed part in our hands.......well, all we can do is state our "personal" opinions. This isn't a witch hunt to see who can trump who, its just a forum for personal opinions, like the o'l saying goes, "A picture is worth a million words" & "Opinions are like A/holes, everybody's got one", those couldn't be further from the truth in this case, all opinions are just that "Opinions".

[JP Love]

Being a Manufacturing Engineer, I know what I see here. I totally agree with Stitch King, factory defect. That area is a raw casting, no material there from the beginning to machine.........

http://i177.photobucket.com/albums/w201/90profx/1-Junk%20Pics/Casting_zpsdaa20f51.jpg~original (http://s177.photobucket.com/user/90profx/media/1-Junk%20Pics/Casting_zpsdaa20f51.jpg.html)Good point from a machinist... JP Love

[JP Love]

I just got off the telephone with Matt Cooley at Mercury Marine. Matt tells me that the new compressor has been completely redesigned. The new compressor has a crank assembly that runs completely though the compressor housing with a bearing at each end. This makes a lot of sense and is a welcome change that will hopefully eliminate these failures. Thats the good news.

The bad news is after $3000 in compressor repairs in 500 hours and Matt fully admitting there is a problem with the compressor design that took 11 years to address, they will not help me out financially in any way. I even asked if they would just sell me one at cost. No handouts but a nice gesture that would go along way toward showing some customer appreciation. Matt said he could not do anything because the engine is a 2003. Doesn't matter that the compressor is a 2008.....

So thats it in a nutshell. They MAY have finally fixed the problem. I will be out another $700 in parts and will never own another Mercury product. I will look for a company that values their customers and can see past a few bucks to retain a future customer.

I will post pics and my assessment of the new part when I locate one.



This thread has been forwarded to Matt and I hope he pays particular attention to the number of views it gets. You deserve a full support and free replacement from Mercury Marine because is a quality control issue... Call this guy again and show im the crank..

[JP Love]

I can see that even the outer surface is off quite a bit, and if I can see it with my eyes, I can only imagine how far out it is when you stick a mic on it. :nonod:About .010''to .012'' by experience..

[Liberator*21]

Let me throw something else into the pot:

One further thing that must be considered in this evaluation, there is "NO" evidence to support it as a scored journal vs cast surface. As a rotating mass it would display smearing to some extent in the direction of rotation, that does not exist in the photo. Since the bearings are of a needle type, hammering would be displayed the length of the journal/needle bearing surface as the journal and needle bearings are directly parallel to each other and therefore would impact the entire surface (had it been there to begin with) and not a local area.

[JP Love]

Let me throw something else into the pot:

One further thing that must be considered in this evaluation, there is "NO" evidence to support it as a scored journal vs cast surface. As a rotating mass it would display smearing to some extent in the direction of rotation, that does not exist in the photo. Since the bearings are of a needle type, hammering would be displayed the length of the journal/needle bearing surface as the journal and needle bearings are directly parallel to each other and therefore would impact the entire surface (had it been there to begin with) and not a local area.
It's a cast issue.... Lack of metal for a perfect journal machining

[1BadAction]

About .010''to .012'' by experience..

:D:thumbsup:

[Mr. Demeanor]

Merc swore me to secrecy on how this was resolved :D

Having said that, this makes me want to open up my new one and have a look.

[powerabout]

Let me throw something else into the pot:

One further thing that must be considered in this evaluation, there is "NO" evidence to support it as a scored journal vs cast surface. As a rotating mass it would display smearing to some extent in the direction of rotation, that does not exist in the photo. Since the bearings are of a needle type, hammering would be displayed the length of the journal/needle bearing surface as the journal and needle bearings are directly parallel to each other and therefore would impact the entire surface (had it been there to begin with) and not a local area.

I,ve seen cranks with a million hours on them and they looked like that. The hard casing has just been worn off. You would think you would get spalling following the rotation but no.
If it was new you would say it was a manufacturing fault.

[pcrussell50]

He said it lasted 200 hrs.If in fact it was like that from the begining it would have made it maybe 20 minutes.When the heat treated outer surface goes that is exactly what it looks like on any outboard crank. hf... Don't really care if he is fortune 500 or not .How many outboards or optis has he worked on ?

yebbut remember, this is a compressor, not a motor. it's only loaded on the intake stroke and at that, only by the force of compression. i can't imagine that it has anywhere nearly the hammering forces applied to it that it would if it was undergoing a power/combustion stroke like a motor does. I'm with the guys that say "defect".

-Peter

[gen2flight]

It is about time to open up a new compressor and verify design changes or improvements to the original. To me it SHOULD have 2 bearings supporting the crank, one on each end, but I think it is impossible to assemble unless both bearings are in the top cap.

[CUSTOM PERFORMANCE 1]

The moral to the story is that if the motor is out of warranty, you are out of luck on the compressors. We lost one in our first 250 XS with about 175 hours, Mercury did not care. No help. We replaced the compressor and sold the motor. The real answer is where the compressor was assembled, "Mexico". You don't think they care about us, do ya. The latest compressor is supposed to be the final fix for the issue, we hope, since we have 3 300XS's in our current possession. However, the cost of the replacement compressor is not really too bad if you think about how much fuel you have saved running an Opti. over non direct injected motors. And when we replaced a 250 offshore with a 250 XS, the fuel savings was a staggering 40%. Just our 2 cents!!!!

[Euroski]

Whats the price for a new compressor? I have a 2007 300xs.

[1BadAction]

Whats the price for a new compressor? I have a 2007 300xs.
750ish, depending on how bad your dealer does you.

[Capt.Insane-o]

list is 792.00.. plus the injector cleaning/replacement.

[pcrussell50]

how sure are we that the new design compressor is supported at BOTH ends of the crankshaft? i've got folks climing my azz on another forum for proof of this. anyone got pics?

-peter

[Wayne Cammidge]

Does not sound like it is much different. Just sounds like they have added an extra bearing in the end cap to support the crankshaft better. Do not know anyway they would be able to get it together unless it was built this way, without a major rework

[pcrussell50]

Do not know anyway they would be able to get it together unless it was built this way, without a major rework

oh. I was hoping they DID do a major re-work.

ninja edit in italics, sorry

-peter

[gen2flight]

My last outing at the end of last year I noticed what I thought was a momentary rod knock after firing up on a cold morning. Thinking I might be developing a compressor problem, I replaced it with a new one before running the motor this year. What I was hearing wasn't related to the compressor, some piston skirt slap as they round up from a cold start. The old new style compressor is sitting on my work bench. I expect to find it in good condition internally when I open it up, hot up here in the north country for a couple more days so I will update after some more serious hours/days of boating /skiing. I'll still go out on a limb and say it can't be assembled with bearings at both ends.

[davemvegas]

Being a Manufacturing Engineer, I know what I see here. I totally agree with Stitch King, factory defect. That area is a raw casting, no material there from the beginning to machine.........

http://i177.photobucket.com/albums/w201/90profx/1-Junk%20Pics/Casting_zpsdaa20f51.jpg~original (http://s177.photobucket.com/user/90profx/media/1-Junk%20Pics/Casting_zpsdaa20f51.jpg.html)

i have seen several wheel bearings that the rollers in the cage look like new. but the race that the rollers ride on have damage that looks about the same as that compressor does.

[4JawChuck]

I've seen this exact issue on HP snowmobile cranks, the technical term is "flaking" and is due to the thin nitrided/hardened layer flexing under high pressure in a localized area which eventually fatigues the harder surface which comes off in flakes creating "casting like" craters etc.

The type of failure shown here is typical of a needle roller bearing flaking failure, in the link below you can see how it looks on a ball roller bearing;

283715

I don't want to get into an argument of how/why/who is at fault or why it happens but I can relate how we fixed the issue to repair cranks that had these issues...had a similar issue with needle roller bearing on Muncie M22 transmission input shafts as well.

You can hardface weld the shaft and regrind so the hardened layer is thicker or you can grind undersize and chrome oversize and then grind to size. Since this part is so tiny welding would have to be done via TIG and thin 1/16 chrome facing rod or the part undercut and radiused so the chrome could be ground flush with the mounting face/flywheel.

My educated guess is Merc nitrided this surface or laser hardened the surface (which I doubt because I dont see the typical discoloration) and its too thin to handle the vibration/load.

Ideally the bearing surface area needs to be longer to handle the load, you could press fit a die pin custom ground to size and install a longer needle roller bearing if there is room. None of this is easy to do and obviously Merc thinks that increasing the rigidity of the crank will reduce failures to tolerable levels.

Its too bad these tiny engineering flaws are ignored during the design phase where they are easily fixed, the occillatory nature of the load on this little crank would be easily handled with a plain bearing if there was enough oil to keep it lubricated but that would require a seal and an oil supply to accomplish.

Seen it many times, chroming and regrind was the cheapest fix but hard facing rod was the most durable...nitriding is just too thin for this application.

[harrells]

Subscribed to thread. What year did this newly designed compressor get installed in the motors? Just purchased a 2012 250 sport XS that was manufactured in Dec. 2012 I assume due to the # 12 being inside a large square on the engine ID sticker.

[tomibach]

model year 2007 225hp 600hrs Optimax (two)..severe galling on crankpin journal, scuffing and scoring on lower cylinder walls....had removed them from my engines and tore them down out of curiosity....always used DFI oil from the dealer...warmed them up, and ran them very conservatively....glad I pulled them after reading this forum...see how long the new and improved ones last...bearings seemed tight although the crankpin needle bearing on the con-rod was fouled with metal flakes

[Mr. Demeanor]

I have about 100 hours on my new compressor which is the longest one has lasted for me. I guess the newer ones are black. My new one was one of the first of the new design and is silver but it does say its made in the USA.

Has anyone had a new one fail yet?

[Promax1R]

I have a 2006 225 Opti with 145 hours on it. How can I check the compressor before I have a failure? The engine runs great and I had rather catch a problem before it hits.

[XstreamVking]

Use a stethoscope to listen to the compressor carefully while motors running. Bad internals make a grinding/knocking sound. Remove the belt and rotate the compressor by hand. Should be smooth with no play at the pulley. Have the air pressure checked by a tech for proper psi. I am sure there are more checks with a lap top diagnostic tool also. Hope this helps.

[boaterok]

With all that play at the crank end whats it doing to the other end of the rod to the wristpin bearing and sideloads on the piston. Is there still damage in the topend that is taking out the bottomend of the compressor quicker.

[Wayne Cammidge]

The Lap top will do nothing to tell about the condition of the compressor, only if it is getting hot.

[jmiller165]

Is the compressor something that should get changed out on my '08 300xs regardless of the fact that it is functioning fine to my knowledge. I have never really checked it but from what I have read I need to relieve the tension on the belt and wiggle it around making sure it is still solidly in place? Anything else or should I just take it to my dealer and have it replaced?

[XstreamVking]

If you have over 400 hrs on it, I would consider replacing it with a new one. I have gotten 800 hrs on one before replacing it and as few as 300 on another. New ones are said to be better quality.

[Promax1R]

I was told by a Merc. dealer they changed internals of compressor starting in 2011. They are suspose to be the best ones to date.

[xskeetshooter]

the early ones made in mexico were doomed to fail..i would look at maybe going to higher precission bearing, standard clearance brs are c3, the br will have markings so look, go up 2-3 numbers on clearance ..the higher the c number the more precise it is,,in turn the rod journal will run more true..just a thought...be prepared to pay a lot for a high c number bearing.

[aRocketScientist]

What an interesting problem. My engine light just came on at low RPM, and i found this thread. From the fix that mercury implemented on the compressor, the compressor had a design flaw. The crankshaft was only supported on one side, with one bearing between the belt pulley and compressor piston. From the description of boat/engine combination, it seems to me that the compressor was bogging down at a bad RPM where it was holding large pressures before it was being injected into the combustion chamber. (Notice the damage to the crank shaft is centered on the compression side of the race.) This large pressure in the compressor, and possibly a resonant frequency at that bog down RPM, caused the crankshaft to rotate slightly causing all the force of the piston to be unequally distributed to the inside of the race. Essentially reducing the size or area that the roller bearing were riding on the race, inside only. (Notice the damage starts on the inside of the race where the roller bearings were transferring all the force from the crankshaft to the piston, instead of having an equal distribution over the entire race) The crankshaft race is heat treated to increase it's strength, but heat treating also makes the metal more brittle, causing the heat treated metal to fail in compression on the bearing side of the race. The heat treated surface flaked off, leaving the more ductile (rough looking) surface behind. Adding the bearing to the other side stops the rotation, even if there is a bad resonance frequency, which would also change with the redesign. It's a design flaw, not really a manufacturing flaw.

Back to cruising the internet to see what the check engine light ON my 1998 Optimax means. It actually goes off when I advance the throttle slightly with no audible increase in RPM and comes ON with a slight decrease in throttle position.

[2stroked out]

Todd D is making billet compressor pulleys. They are a little lighter and vented should run cooler.

[2us70]

I have a 2001 225 Optimax which is all original except for water pumps over the years. I don't know how many hours I have on it but it is quite a few. Do I need to think about rebuilding or replacing my air pump?

[XstreamVking]

Have it checked for proper air pressures and possible leaking air the from the air hoses. Some go many, many, hrs. Some crap at several hundred. I have had several compressors last for nearly a thousand hrs before any problems.

[Onetime]

I'm a little late to this thread but wanted to interject here. 4JawChuck is spot on. To the engineers that posted saying it was a factory defect and machined that way I disagree. While I agree with them on the design flaw the failure is due to the case hardened bearing surface flaking off. Have seen this before on many roller bearing crankshafts. The hardened surface, which is 60 RC or better, is being dislodged from the core material. You can go to most any roller bearing manufacturers engineering books and even in a Mercury service manual and see photos or drawings of this exact nature failure. This is exactly what 4JawChuck did. Those photos and descriptions are from manufacturers books. By the way love your screen name "4JawChuck".

[Onetime]

Has anyone seen the oil lines being connected wrong to the compressor? Just ran into this. One line going to the compressor is a larger diameter. It is direct from the oil pump and feeds oil to the compressor through the upper fitting on the compressor. The two lower hoses are drains from the compressor which then feed the crankshaft mains.
Just saw the feed line going to one of the bottom drain fittings. Came from the factory this way. Wouldn't have noticed it except for the oil leak from the larger hose to the smaller fitting.
How does the path of the oil go in the compressor?

[pcrussell50]

ok, so so far, we have some pics of a bad compressor crank. debate rages as to whether it's damage is due to failure of the hardened surface or the rough surface left after casting. I gotta guess that even though the two look similar, (and I have a Mercury manual which shows the pics of a damaged hardened surface), someone who really knows the difference can tell, because even though sand casting and hardened surface failure may look similar, there is still a difference. there has to be.

I'm still in the camp of those who thinks it looks like an un-machined cast surface. I've seen plenty of cast surfaces. But I've never seen hardness failure in real life, only a black and white picture in the Mercury manual, so I can't speak from the experience of having seen both.

-peter

[Onetime]

Been thinking about this. Really it doesn't matter the cause. Regardless it's still a failure and unfortunately Mercury is not standing behind them in any way unless you're still under the original factory warranty.
Bottom line it sucks.

[Roblunday@gmail.com]

Welcome to big black.....that's there profit numbers they are referring to....
mercury marine has the weakest warranty in the industry. Hang a honda if you want customer appreciation