Volvo Penta GXi-J 5.0L Getting Fuel in Oil

mattcamp

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Don,

I have learned so much from your posts/responses to posts. Sorry for posting the q in the wrong thread before, this is the first time I have ever used any kind of forum etc.

I have a mystery problem that two dealers have not been able to figure out. I am getting a significant amount of fuel mixed into the engine oil. I have checked the injectors, no problem. Checked the fuel pumps, no problem. Checked vent line from fuel pump, no problem. Replaced the plugs, distributor cap and rotor, and still getting fuel in the oil.

Engine is a Volvo Penta GXi-J 5.0L - 2009.

Thanks for your help!

Matt
 

Don S

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

Do you do a lot of idling or low rpm running? Is the engine up to 160?-170? even if it shows ok on the gauge, make sure the sensor to the ecm is showing the same thing.
 

boatguya1

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

Do you do a lot of idling or low rpm running? Is the engine up to 160?-170? even if it shows ok on the gauge, make sure the sensor to the ecm is showing the same thing.

Don,do you think a leak in the fuel pressure regulator allowing fuel into the vacume hose to the regulator might do this?

OP, per Don's idea with the computer not seeing the correct temp you might pull the lead on the temp sensor for the computer and look for corrosion. It also would be interesting to see if the fuel pressure holds after you turn the pumps off or is leaking down right away.

James
 

Don S

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

I have no clue about the pressure regulator. If it was bad, I would suspect running problems if the diaphragm was bad in the regulator. I would hope the 2 dealers actually did a fuel pressure check. I also assumed (stupid on my part I know) that the vent line from the pump is vacuum line for the regulator.
 

boatguya1

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

I have no clue about the pressure regulator. If it was bad, I would suspect running problems if the diaphragm was bad in the regulator. I would hope the 2 dealers actually did a fuel pressure check. I also assumed (stupid on my part I know) that the vent line from the pump is vacuum line for the regulator.

"Vent line" gives me another thought, Maybe the float in the vapor seperator is stuck open. Where does the vent line from the vapor seperator go on those? I guess a good question would be how much fuel in the oil are we talking about and how long does it take to happen, OP?

James
 

Don S

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

There is no float or VST on the MPI engines.
 

boatguya1

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

There is no float or VST on the MPI engines.

Looking at the Volvo EPC it appears there is a VST or fuel resivior on the 5.0GXi-j. What else would the tank thing the 2 pumps are on be?

James
 

mattcamp

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

James,

After running the boat an hour (multiple times after full oil/filter change) getting about 4% oil, reducing the oil viscosity by 1/3 or so.

Matt
 

Don S

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

Has your Volvo dealer contacted Volvo Penta tech support? Your engine should still be under warranty, and if the dealers can't figure it out, Volvo normally sends a rep to that dealer to find the problem.
 

boatguya1

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

James,

After running the boat an hour (multiple times after full oil/filter change) getting about 4% oil, reducing the oil viscosity by 1/3 or so.

Matt

Is the boat running rich, sooting the transome smelling like fuel when running, starting hard warm?

Don is correct above about keeping on the dealer about this. If they can't figure it out they should get a tech rep out there to do it. Are you still in warr?

James
 

mattcamp

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

It has already been to two dealers and just brought it to the 3rd on Saturday. The first two seemed unwilling to involve Volvo after they couldn't figure out.

The boat started great and ran great, but did run very rich.
 

Don S

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

It has already been to two dealers and just brought it to the 3rd on Saturday. The first two seemed unwilling to involve Volvo after they couldn't figure out.

Sure sounds like dealers you don't want to deal with. They are probably afraid to have the tech reps in their shops.. I have delt with them on several occasions and always learned something new from them, and they were always very friendly.

The boat started great and ran great, but did run very rich.

That could be because the ECM is seeing a cold engine. The engine may be warm and the gauge show warm, but the ecm sees cold and causes a rich condition.
Have them check the fuel pressure regulator vacuum hose. It may cause the fuel in the oil, not sure how it would make the engine run rich though.
 

mattcamp

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

So Volvo has conducted every test imaginable and even though the oil (after an oil change) has 2.52% fuel dilution after being run about 3-4 hours is saying that there is not a problem with the engine.

Thoughts?
 

Don S

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

Well, if Volvo conducted the tests, then they should have been able to come up with a reason.
Just curious, when you say Volvo, do you mean your local dealer, or the actual Volvo reps that actually come out to visit dealers when they can't figure out a problem?
Some of the dealers shouldn't be allowed around MPI engines.
 

mattcamp

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Re: Volvo Penta GXi-J 5.0L Getting Fuel in Oil

The local dealer working under the direction of Volvo Tech's. It was Volvo that wrote me their findings that after working with the dealer that it is an acceptable level of fuel...
 
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