Opti-max ?

[Greg Moss]

All right now here is one for you guy's. Got a 1999 Opti max that when you try to start it, it fires and dies. If it does stay running and you advance the throttles it will not pick up speed. The DDT tester passes all test. TPS reading do just what they are supposed to One goes up and the other goes down in specs. Run the motor for a while and it fills the tester with TPS faults. Why? and what do you think is wrong with it . Voltages for the TPS are good. what else can give me a TPS fault? Also the check engine light comes on and the horn beeps. The book says TPS . whenthat happens but the TPS'sboth read good. One more thing the fuel and air pressure are both good. Air is 90 psi and fuel is 75-80.

[sosmerc]

These engines can be strange, huh?! So TPS values change properly, yet no speed increase? What about MAP sensor? Does its value change when you move throttle? What if you disconnected the MAP sensor and pulled different amounts of vacuum on it using a hand vacuum pump? If this all checks out, what about putting in a few drops of extra fuel in thru the intake to see if speed picks up? If you disconnect various sensors (except for the crank position sensor) you should experience some sort of change. Engine won't run with crank position sensor disconnected.
So you have run the auto test sequence? How about manual running "special functions" tests like cylinder drop test?
The only real problem I have experienced with these engines is fouled spark plugs...and the DDT won't give you any clues there.
Probably should be step one...new set of plugs.

[Greg Moss]

This is one of those buddy deals:D you know they sold a perfectly good motor all I have to do is rig it for the guy. well the thing don't run. I haven't tried the MAP yet haven't had it running long enough to pull sensors loose while it is running or run the self test to drop cylinders. Will try it and plugs in the morning. Rigged the perfectly good kicker motor on the boat also. Hit the key and the starter is locked up. ever have one of those days:rolleyes:

[sosmerc]

I know exactly what you mean! I bought the latest DDT Cartridge, and the correct factory manual, and the required 19 spline adaptor for my dyno, all for this 2000 280 EFI engine that came in today and somehow the guy thought I was going to work on it while he watched and figured he have it back today!
I don't know what I said that gave him that impression, but I rarely allow customers to stand over my shoulder as I work and I NEVER promise a completion time because there are too many variables that can arise...especially on a Saturday...and today was no exception!
What's really weird is the guy's name is Todd Love and my name is Steve Love. There aren't many folks around my area with the last name Love. On top of that, he has a summer place that is straight across the Hood Canal from my place. He probably heared me running his engine today!! Guess I may be seeing alot of him this summer....hopefully waving at me with joy as his Cougar cruises my at an easy 80 or so!
Anyway, good luck on your Optimax. When things are working properly they do run pretty sweet....but they are a bitch to rig and work on so you have my sympathy! I sure hope the new 3 cylinder 115 Opti is better packaged for rigging and service!!

[Greg Moss]

I have worked on a bunch of opti's but this is the first one I ran into that acted like this. Most times the ddt will tell you everything that you need to know but this one is acting weird.

[LARRY D]

Gregg you might want to check the tracker valve. fuel psi should be 88 to 92 & air pressure 78 to 82. the tracker valve keeps the fuel pressure 10lbs higher than air pressure. Later Larry D.

[sosmerc]

Greg, one thing that is sure nice about the DDT and the PCM 555 is the "system info" feature. You are pretty assured of getting the correct specs for the engine being worked on! Now, if they would just include a complete service manual on there as well...no need to order more manuals!!!:D

[FlatsMaster]

greg, i also own a optimax had similiar problem- motor whould run than stal took it to mercury same thing DDT came up with all kind of wrong codes took it some where else same thing, so brought motor home took plugs out turned over, and took fuse out of fuel pump got all the oil and fuel out of cyl's put new plugs on, fuse back hooked water hose and fired motor up at about 2100 rpms ran rough but got motor to keep running pulled fuel injector plugs off one at a time still nothing motor still at 2100 rpm's pulled of direct injector plugs of one at a time found that cyl's 3 and 6 direct injectors were not working mechanicly, but good ohm readings on them, took rails off and pulled DFI'S off cleaned them and got them to work , put back on and motor and fired right up 2 mechanics 2 dealers 2 DDT'S these optis are tricky also , be careful with those DFI'S they sure are expensive and also the seal around them good luck just my 2 cents Jorge

[sosmerc]

Glad you got it fixed. What I don't understand is why the mechanics could not detect this by doing a cylinder drop test with the engine running. With the DDT you can shut off cylinders individually at any rpm....and if there is no drop in rpm or power you could assume that either that cylinder was not getting fire or fuel. You came to the same conclusion basically by doing the same think, only manually shutting off parts of the system by disconnecting pieces of the system.
What did your plugs look like?

[sosmerc]

Jorge, I just re-read your post and my reply. In (slim) defense of the mechanics, I just realized that your engine probably wasn't running long enough for them to perform this "cylinder drop test" I referred to. So I guess they should have removed the injectors and then had the DDT fire them one at a time so they could visually verify whether or not fuel was being delivered. As you said, these engines can be tricky and I've had a couple that tested perfectly with the DDT, but that didn't tell squat about the condition of the plugs...and that turned out to be the problem.
If one could figure out how to do a fuel pressure drop test while having the DDT run the injectors individually for a set period of time you could then establish a faulty injector. I do this on the EFI engines easily.

[FlatsMaster]

sosmerc, i,m not trying to put the pros at merc down in no way, or the DDT, wish i had one own 2 optimax's just saying i coulnt wait any more dealers had boat for two months and with warranty gone it was getting expensive so i took it into my own hands, first thing i noticed was that cyl's 3and 6 plugs were alot cleaner than the rest so that lead me to checking all ohms on everything and then to the injectors, glad i found problem coulnt wait to get back to chasing permit, bonefish and snook goodluck sosmec just shared my experience with thos tricky opti's besides that problem i thik there great motors, my neibors are friends with me again no loud exhaust or oil smoke. goodluck Jorge

[delawarerick]

I asked the techs at work and everyone had an answer. Bull sh$t all the directed injected engines (any flavor) have some problems and software for scaning still leaves some gut feelings a mechanic gets. Had a ficht 99 that would not run under load on #6 injector tested and all. Sent it out and had the computer scanned and a wire had come unsoldered from the board. Every test on the computer read normal. Tech support had us pull the heads so many times we even sent them the computer they sent it back. I really appreciate the knowledge surrounding Mercuries. Thanks Rick

[hydrostream1]

Did you check grounds,loose pins in the connector at the ecu and the tps.I had several engines give false or erronius codes,had a merc sterndrive boat with the 555 ecu throw a code that was not in the trouble code list! called merc tech,they were scratching their heads.finally i started wiggling connectors,and discovered a loose pin in the ecu connector,tightened it up with my pick,fixed it.Had a tiara 31ft fishing boat with two crusaders 8.1`s with a crank sensor code still ran,but would start missing at 3000 and above,replaced the sensor,still did it.tried swapping ecu from the other engine,nada.Started pulling at different areas of the wiring harness it started acting up bad.I traced it down to the connector at the crank sensor,the little pin inside the connector was a little loose fitting on the crank sensor pin,the vibration from the engine,set it off.I tightened it up no more problem.Damn basic crap.just my two cents

[sosmerc]

The operative word being "crap". Maybe computers don't belong on outboards. This stuff is so darn sensitive and the DDT then displays erratic information that you can't trust or believe. I guess the engineers have a long ways to go to achieve the same reliablility the auto industry has. (at least my experience with modern cars that I've owned).
But you are so right hydrostream 1....it's the basic stuff like loose wires and bad connections that can drive you nuts....as well as the computer.

[MIKE'S MIRAGE]

GREG, WHAT SPARK PLUGS ARE IN IT. IF THEY ARE THE CHAMPIONS, THROW THEM OUT. RUN THE NGK PZFR5F-11'S. ON THE DATA MONITOR SCREEN, WHAT IS THE VOLTAGE SPEC FOR PWR 1 VOLTS? IF THERE IS TOO MUCH PRE-LOAD ON THE THROTTLE CABLE, THIS WILL ALSO CAUSE THE FAULTS. LASTLY, CHECK THE CRANK POSITION WINDOW, THE AIR GAP MAY HAVE GOTTEN SMALLER WHICH COULD ALSO CAUSE THIS PROBLEM. HOPE THIS HELPS. MIKE

[Markus]

11s.

That is really, really cold plugs.

Why?

[MIKE'S MIRAGE]

THAT'S WHAT THE MFG CALLS FOR. I BELIEVE DUE TO EMISSIONS REGULATIONS.

[Greg Moss]

I put a new set of plugs in it and it will sit here and idle. Going to try it in the river today. The guy has already spent $700 twice at Meek's here in Kemah tring to get it to run and he didn't enlighten me to that fact before he sold the motor.:( He is bringing all the service order copies he has so i can see what has been done to it before. Man I hate haveing to work on something that some one else has first. at least I know what ever they did at Meek's is not the problem so I can not waste any more time checking what they did. Oh and the plugs looked oil fouled big time, didn't think these motors run enough oil to blacken a plug like that.

[sosmerc]

I've been told that when you tear down these Opti's you will find they have alot of oil on everything inside. They are a different animal and I guess that's the reason Merc has developed the Optmax oil and it probably should be used. The oil has different properties and is not TCW III rated...in fact Merc DOES NOT recommend its use in anything but Optimax.
Good luck on your river test....I hope you have a better day than I did yesterday with my customers 280.

[Greg Moss]

What happened with the 280? I would rather work on those than these damn Opti's Got a Foutain here with 2 Opti's on it Had reman powerheads installed all I got to do is hook them up and get them runniing. Oh Boy:rolleyes:

[sosmerc]

Got the 280 on the dyno. Idle speed in N about 1100 with back pressure from cattle feed tank. First couple of times it died when put into F. But after a bit it settled down and I could get it to idle in gear 875-950...fairly stable. With the engine in F I could depress the shift "interrupt" switch and noticed that nothing special happened. The rpm didn't change and the timing didn't change. The Engine was almost impossible to shift from F to N.
So I removed the shift cable and decided to try and shift by hand while running (just to confirm the problem was not the cable or control). The engine suddenly would not shift into forward. I could get N and Reverse, but no more forward. I experienced this once before on a 2002 Opti that had about 5 minutes on it.
The pin that connects the clutch to the shift cam carrier broke (right at that thin area). I'm positive this damn thing has broken at the same spot.
The engine is under warranty until June so I guess I have to advise my customer to take it back to authorized dealer. What I have found out it that not long ago a local dealer replaced a broken propshaft and forward gear on this motor. Maybe there were other "stressed" parts they didn't replace? So in order to be ready to work on this thing I bought latest DDT cartridge, factory manual, and 19 spline adaptor for my dyno and now I feel I've really done nothing for myself or my customer.
I did clear all the fault codes before running and in the short time I ran it I would get the #5 LCD coming on. DDT Manual says #5 is for Coolant Temp Sensor. Temp readings were normal and the ohms test on the sensor was within spec. #4 LCD came on once as well, DDT manual says that's for TPS and (Not Used) On this engine, the DDT doesn't seem to be helpful, except for the run history.
One other observation, with engine idling around 900 - 1000 in gear, the timing is at about 10 degrees BTDC. I know it's not adjustable, but doesn't that seem abit high?
Sure like to know what that shift switch is really supposed to do.
Damn manual doesn't say anything. When the switch is closed it's about .3 ohms...when open my Fluke 88 shows high M ohms, but not complete "no continuity". If I disconnect switch leads with engine running in gear, makes no difference to rpm or timing.
Good thing I got so much testing done before the gearcase decided to quit.

[Greg Moss]

What software are you using? I have found TPS problems with the DDT you need to look up sensors on the screen. you need cartridge 91-8222608-5or 6 to test that motor. It will test every thing you need. TPS for that motor only funtions below 2500rpm from then on rpm is controlled by the crank posion sensor.check TPS volts to make sure they are between .80/.82 volts at idle. on the ECM the plug that is closet to theend with two mounting bolts, Pin 14 is the switch input ground that pin with the motor running and see what the motor does that will tell you what the shift does or if it is working.

[sosmerc]

The software I'm using is the -6 (latest version I was told). TPI set to .801 volts. The DDT manual that came with the cartridge is 90-825159-4
Page 169 and 170 is LED switch definitions.
Why would LED #4 light up?
If you ground pin #14 what SHOULD happen?
What about this gearcase problem...have you seen this part fail before?

[sosmerc]

One more question Greg, before I go out to the shop and attempt to find something I can actually fix.
The part number on the box for my software and manual is 91-822608 6
Yet the cartridge is labeled Ver. 5.0 '91 '99
I already have another cartridge that is labeled the same and the manual with it is labeled 90-825159-4 but the print date is 699 whereas my new one shows a print date 799.

Looks like they did some minor updating and I paid thru the nose for it and maybe I didn't even need it. I'm going to plug in the old cartridge and see if it will also "communicate" with the ECM.

[Greg Moss]

I think the dates on the cartridge is the dates they copy righted it. Don't think it has anything to do with the date it was updated. Pin 14 should either kill the motor or change the timeing you wanted to know what the shift switch does ground that pin and see what it does with the motor running I don't have a 280 here right now to try. I am not sure if the pins are the same witrh these Opti's but I will lookand see. If they are the same i will try it on one of these too.