2004 225 Optimax Problems

[wantahappymotor]

I am looking for a little help. My 225HP Salt Water Optimax is having a couple problems mostly around idle. This is a 2004 with about 575 hours. It seems to have started months ago with an oil discharge in the water at idlel. The engine sputters/coughs and then oil is in the water. I have had 3 mechanics look at it.
The last one feels it is the combination of regular gas and non branded oil.
I replaced the oil with the Mercury brand and I'm in the process of using a 50% mix of new high test gas with the old.
At idle, the engine sputters/coughs with oil in the water and now also surging. The surge seems like 100-200 more rpm. One extreme to the other. NO Ethenol yet.
All plugs replaced and water filter.
Any ideas?

 

[woody66912]

Re: 2004 225 Optimax Problems

I'm not sure what was all looked at already.but when optis have idle problems i always check the flowing /fuel lift pump diaphragm / witch would let raw fuel into the engine block. [air] side of fuel rails for excessive fuel in the air side.witch would indicate a failed tracker valve or fuel pressure regulator diaphragm.also the air handler on the front of the engine can be removed to check the reed valves for cracks or chips.not sure if any of this helps.

 

[wantahappymotor]

Re: 2004 225 Optimax Problems

Woody66912
I appreciate the detailed response. Can you break that down a little for a layman or should I just pass you suggestion on to the mechanic?
He did just replace the engine oil reservoir and sensor due to an alarm. Turned out to be a defective sensor.

 

[hamit59]

Re: 2004 225 Optimax Problems

Hi really need some more info. What is the fuel rail pressure? and what is the air rail pressure? fuel pressure should be 80psi and the air rail should be at 90 psi. you don't have much wiggle room in these specs if either is off more than 5 psi you will not get the fuel bloom your looking for in the cylinder. Most time i see the fuel rail down on pressure causing lean burn if that the case then you would need to look at the high pressure fuel pump.if it's high on the fuel side then you may have bad fuel regulator causing a rich burn. if the air rail pressure is lower than 90 psi check the relief valve if that's ok then it would be time to rebuild the compressor. If there is not enough air to push the fuel into the cylinder then you fuel/air mix would be wrong and you would get a rich burn and maybe plug fouling or over fueling ie: rainbows opti's can run without the compressor for a short time but you'll be running a rich mix opti 's run good when there right but you have to make sure you do all the trouble shooting in the right order

cylinder compression
spark on all cylinders
air rail pressure 90 psi
fuel rail pressure 80 psi

 

[happymotor1]

Re: 2004 225 Optimax Problems

Woody66912,
Thought you might appreciate below.
Langpie,
I believe my engine is fixed. I willl test this weekend. I had a Mercury service company look at it. He said there was a hole in the diaphram between the fuel and air pressure.
I have listed a response below that I got from an earlier thread. The problem was that I didn't know what "woody66912" was talking about. I should have gave his reponse to the last guy servicing the motor.

woody66912
Petty Officer 2nd Class
Join Date: Jul 2008
Location: northwestern wi
Posts: 152

Re: 2004 225 Optimax Problems

 

[toddieie]

Re: 2004 225 Optimax Problems

If you have any diaphram issues you can contact thepelicanservices dot com - they can fix the diaphrams without you having to replace the fuel rails!! This will save you hundreds of dollars!! Good Luck!