Sick 98 Promax 225 SS

[JR IN JAX]

My Timex-like Promax has gotten sick. It will only turn up to 4K when I start off, but will not break the 30" ChooperII loose anymore and has a hard time getting on a plane.
I have also lost 1000 RPM [6K] of the top.

Compression was 140 on all six holes and I am running the stock ECU with brand new BUZHWs. I just had the TPS checked on a DDT [OK] and had to have a waterpump changed due to picking up shells in a shallow lake.
My fuel flow is about 18 GPH [Floscan] when it is struggling to get on a plane.

My major problem is that my long time Tech is getting older [late 70s] and he is scared to ride in my boat to witness the problem. He does not have a test tank since he is on the river.

I appreciate any suggestions.

[slowaction420]

clean the vst yet?

[JR IN JAX]

No, not yet but I will tonight, thanks for a good idea since we are all getting ethanolized.
I would really like to take the boat to St Augustine tomorrow if I can get it healthy.

[HighVelocity]

Maybe the fuel pump is on it's way out. Powerplay25 had RPM issues for months and his pump finally took a dump.

If you have good compression, then that leaves fuel or timing advance.

Ed

[JR IN JAX]

Maybe the fuel pump is on it's way out. Powerplay25 had RPM issues for months and his pump finally took a dump.

If you have good compression, then that leaves fuel or timing advance.

Ed
Ed, how did he diagnose his fuel pump issue? Was it a pressure or a volume problem? My pump has about 1500 hours on it so it is not a "Spring Chicken".

I just bought enough fuel injection type 3/8" fuel line to replace all the Ethanolized lines in my boat.

I checked the timing this week 25* BTC and the Idle control is eliminated.

[Bartman39]

Something that doesnt tell all but can sometimes point you in the right direction is take a look under the flywheel at the stator...? Have a guy over at BBC was having a problem with a Promax 200 that would not turn over 5500rpm no matter what prop and just happened to look at the stator and saw a melted coil... :eek: Even if you see nothing a DVA meter might shed some light too...

Just a thought...?

[JR IN JAX]

Thanks for all the help everyone.

I am hoping that I found the problem this afternoon. I pulled out all of the fuel lines and found one that was soft/collapsed where it made a turn coming out of the prefilter. Hopefully my problem was fuel starvation.

I also bought a fuel rail pressure gauge on my way home from the office and my VST pump went right up to 35 PSI and shut off.

I am going to put it in on the St Marys River tomorrow [instead of St Augustine] hopefully it is fixed and I won't get a ticket like the last time I took the boat there.

[K-Dawg]

What time you gonna hit the river here and where. Might see ya out there.

[JR IN JAX]

What time you gonna hit the river here and where. Might see ya out there.
We are going to launch at Scott's Landing [US1] and hope to be in the water just after 10 AM. We'll probably stake out a sand beach a couple miles East of the ramp on the Florida side. We'll also have the PWCs too.

Watch out for Barney Fife in the GMP boat or it will cost you $86, the Florida guys are nice if you aren't drinking. For some reason if the people on the Georgia side see an Allison they call for Barney.....

[JR IN JAX]

It was not the collapsed fuel line, it is still sick, sounds like it is only running on 4 cylinders and will hardly get on a plane. I am going to try a different shop next week if I can find one that has a test tank.

[olmo40]

Unscrew your water seperator filter and empty the contents into a container ,to check for debris,I have been finding many with little black particles lately ie deteriorating fuel line . You can also do a search on checking spark here .Im assuming fuel as you have had a DDT scan .

[myron]

JR look at the back of the coils, take the rubber cover off and see if they are cracked, had one give me fits one time and that was the problem

[chad202]

Check the wires coming from the regulators/rectifiers and make sure not of them are resting on a sharp angle that has cut thru the insulations making it go to ground. Same thing happened to my 99 promax. Chased it for a while before finding.

[JR IN JAX]

Thanks, Guys, I will give them both a look. I want to get it fixed before I put it up for the Winter.

[HighVelocity]

Ed, how did he diagnose his fuel pump issue? Was it a pressure or a volume problem? My pump has about 1500 hours on it so it is not a "Spring Chicken".

I just bought enough fuel injection type 3/8" fuel line to replace all the Ethanolized lines in my boat.

I checked the timing this week 25* BTC and the Idle control is eliminated.


Hey, just got the latest on Powerplay25, It wasn't the fuel pump, as Dave originally though!!!!!!! It was infact clogged injectors, 3 or them to be exact. This comes from Fuller's Marine and they are very good mechanics there. The injectors are going out to Brucato to be fixed up.

Dave's motor ran good but wouldn't pull the high RPM's and then it just got worse and worse. Maybe another ethnol issue, screwin things up??

Ed

[JR IN JAX]

This is possible since I took on a load of crapgas at a marina on one of the lakes in North Ga. Maybe it made it through the double filters and did the injector in.
Jack Barsh told me to take it to Charlie at River Marine here in Jax. I will let you know the outcome.

BTW what is with the little green dot by our location? Does this mean that I have a reputation level of "Manure"?

[HighVelocity]

HAHAHA I think the green dot means we are working on the site.

I used to live in GA. Went to Lake's Linear and Altoona when I lived there. Those lakes are clay lakes, and Altoona gets piss warm in the summer, nasty.

Anyway, good luck with the motor, I would get your injectors cleaned up if you have a lot of hours on the motor. If your running lean, you could slowy roast the motor till she squeaks, that'd be bad.

Ed

[JR IN JAX]

The new Techs looking at my sick motor just told me they thought that my newest [6 month old] switch box dropped voltage, but they went back to verify it and the voltage was back.

They also commented on what I had noticed, I could pull quite a few random plug wires on either bank at my 600 RPM idle and it made little difference in the idle.

I think they are going to water test it.

[HighVelocity]

Well that would be great if they could water test the boat with some type of harness plugged in to the motor. This way they could test everything under a load and see what's out of spec.

[JR IN JAX]

I wish they had the large shaft test wheel so that could do static run-ups.
Hopefully they will nail it down, they are certainly trying to.

[JR IN JAX]

Well the latest saga of the sick Promax.

They found the high pressure hose had shed some debris that was partially clogging the injector screens, even though the VST was clean inside.

They took it out for another water test and it jumped out of the water just fine and then died, which is a totally different problem.

It can be recranked almost immediately and will do the same repeatedly.

They hooked the tank straight to the motor bypassing the filters and Floscan and it still did the same.

They determined the fuel pump must be shutting off. They called Merc and Merc thinks the ECU might be going bad and shutting off the pump.

They are going to try another '98 20" shaft Pmax 225 ECU [mine is a 15"] that they have in stock and water test it again Monday.

[myron]

JR dont you have an ACU?

[JR IN JAX]

I have it up at Tony B's getting a steamwheel pigtail put on it. I ran the OEM Merc the last of the Summer and it did OK.

[JR IN JAX]

I just went and picked up my toy.

They put their own ECU from a PMax powerhead they have in stock and it jumped out of the hole and kept running, so obviously my stock ECU is dying or like Charlie mentioned, maybe the ECU was getting hit with over-voltage which will shut off the pump too.

I bought another new regulator to replace the one that was original [the other one is just a year old] just to make sure I have nailed down the possibilities.

Hopefully when my ACU gets back, my toy will be 100% again.

[bigantmitch]

Had a similar problem with my 2000 225 Pro Max Idles fine then wouldnt go over 3000 RPMs. Changed power packs still nothing. checked comp on all cylinders found that my divider gasket was leaking water into no. 5 cyl. Changed all gaskets compression on all cylinders was perfect. Now it wouldnt even come out the hole. Timing light showed all 6 cylinders hiiting on idle. But when we gave it throttle the left side 1,3,5 quit firing. Stator looked fine no discoloration or melting. Checked ohms on stator, still fine. Changed wiring thinking I had a melted wire. Problem still existed. Changed Stator. PROBLEM SOLVED.....Ha Ha and only 1200.00 later I was up and running.

[JR IN JAX]

Between gearcases, electrical, wiring harnesses, water pumps ect... I have close to 10K spent on mine already this year in repairs. I have thought about changing the stator but it always checks good and they even pulled the flywheel to check the magnets/stator.
My Nephew wanted to sell me his sweeeet running '05 280 for 5.5K, I am beginning to think I should have done it.
The accessories to my engine have close to 1500 hours on them which is a lot of the cause of my problems.

[bigantmitch]

Not saying it is but mine looked brand new....coils looked great.....ohmed 1300 on high and 1295 on low......but it was the Stator. Had my mechanic baffled said hes never seen one check perfect and look perfect and be bad.....

[Powerplay25]

Jr.

The injectors on my port side motor were out of wack and needed to be serviced. That was problem number one.

Just found out today the bigger problem with my Pro Max is four out of six sleeves have turned.

Hopefully that is not your issue.

[whipper]

Mine was doing the same thing JR a few years back. I ended up buying a half a motor. I changed more things than one at a time like a dummy so never did pin point the problem. It was my ECU,Stator, Switchbox,Diaphram pump spring, Coils or water in the gas.:D I changed out all these and she,s been running like a champ ever since.:thumbsup: I do think it was the stator though? She would idle great take off some times OK then die. Start sputtering some times then off plain. Always would start and idle. The stator checked out ok it was only under load that it wouldnt. I had lots of crapy cracked coils. Good luck JR youll get er done soon Im sure. 225 problems can sure drive ya nuts!