Volvo Penta 3.0 Oil on spark plugs

Kronoss

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I recently replaced the gaskets and resurfaced the manifold/riser/valve cover gasket, and removed the exhaust flapper, that was jammed, and causing water to rush back into the engine.

Now my water in oil issue, seems to be fixed, boat runs fantastic, but after about a 30min to 1 hour ride, after i stop the engine, my spark plugs fill with oil, and kills the spark, to the point i cannot start it anymore.

Anybody else ever experience this ? Im thinking stuck piston rings. I did put marvel mistery oil in the piston chamber and let it soak for days.
 

Walt T

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Re: Volvo Penta 3.0 Oil on spark plugs

Can you post a picture of the spark plugs? How long was there water in the cylinders, if any? Any smoke?
 

Kronoss

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Re: Volvo Penta 3.0 Oil on spark plugs

132724.jpg


Water in the cylinders is unknown, because I bought it like that, and fixed the manifold/riser.

Smoke, is non-existant when you first start it, then after a few minutes, just a little bit of smoke. Almost looks normal.
 

aerobat

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Re: Volvo Penta 3.0 Oil on spark plugs

visible smoke on the 3.0 is definitly not normal . first check - oil level ok, not overfilled ? does the engine use up oil ?
 

Kronoss

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Re: Volvo Penta 3.0 Oil on spark plugs

might be smoke, or just water vapor, i actually put my hand it it, and it seemed to be water vapor.

One thing that happened today, is I removed the dipstick while WOT on the water, and it was spitting out oil through the dip stick hole. (with dipstick removed)
 

Walt T

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Re: Volvo Penta 3.0 Oil on spark plugs

Ok that is cranckcase pressure and should NOT be there. Make sure the PCV system is working. If it is.......... Compression check time. And it doesn't bode well.
 

Kronoss

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Re: Volvo Penta 3.0 Oil on spark plugs

Compression test returns 150-170 psi for every piston


Make sure the PCV system is working.
Im not sure what this means :), what part of the engine should I check/replace ?
 
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Kronoss

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Re: Volvo Penta 3.0 Oil on spark plugs

I did another compression test today with a tester i got from harbour freight. and this time i let the engine turn over about 3 times per cylinder while tester plugged.

Results:
1. 215 psi
2. 280 psi
3. 210 psi
4. 170 psi

While i had the compressor attached, the motor was squirting out water/oil mix from the cylinder

Here is a video of it: 2013 10 24 19 42 45 - YouTube
 

Walt T

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Re: Volvo Penta 3.0 Oil on spark plugs

Wow. Thats a pretty good squirt.
Those are pretty high numbers. I've used harbor freight stuff and they usually work pretty good but your tester is suspect. You definitely have a problem. Oil and water kinda makes me think head gasket but that much oil in the cylinder is a lot. Manifold/riser will allow water into the cylinder, as will a head gasket. I'd say it's steam not smoke, and you should plan on removing the head. Oil gets in maybe valve seals, oil control ring, crack or hole somewhere. But it would smoke like crazy when running, and be bluish. I'm missing something. I'll think about it while I have morning coffee and walk the dog. Dog is an idiot so he can't help much. Hopefully someone else will chime in.
 

bruceb58

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Re: Volvo Penta 3.0 Oil on spark plugs

While i had the compressor attached, the motor was squirting out water/oil mix from the cylinder
What do you mean by that? Sounds like you bought a cylinder leak down tester.
 

Kronoss

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Re: Volvo Penta 3.0 Oil on spark plugs

Well, I found a major problem today, my manifold has a huge internal crack in it, its letting water in at a very high flow rate.

Do you guys think i should pull the head off and replace the headgasket anyway ?
 

bruceb58

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Re: Volvo Penta 3.0 Oil on spark plugs

That explains the huge PSI numbers. You had water in there. Lucky you didn't bend a rod.

In post #3 you said you fixed the manifold/riser. What did you fix?

Your head gasket is probably fine.
 
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Kronoss

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Re: Volvo Penta 3.0 Oil on spark plugs

That explains the huge PSI numbers. You had water in there. Lucky you didn't bend a rod.

In post #3 you said you fixed the manifold/riser. What did you fix?

Your head gasket is probably fine.

resurfaced the riser and manifold, and new gaskets. Next time i will know better and perform a leak test on both.

Riser seems good no leaks, but manifold leaks very bad. Ordered a new one from ebay for 320 bucks. I think Riser was recently replaced, it is in pretty good condition, so I will probably use the same riser for a couple more years until it breaks.
 

aerobat

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Re: Volvo Penta 3.0 Oil on spark plugs

Do you guys think i should pull the head off and replace the headgasket anyway ?

i would replace the manifold and look. but be aware a broken manifold does not in any way explain oil in the cylinders, so be prepared you may have additional damage - head gasket or the head.
 

Kronoss

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Re: Volvo Penta 3.0 Oil on spark plugs

re-ran compression test without manifold on, and waited for the water to evaporate in the cylinder. new numbers are:

1. 180
2. 180
3. 180
4. 150

I think the oil in the spark plugs was actually water, mixed with oil, slushing up from inside the engine, and slushing off the carbon build up inside the manifold and back.

It was not very oily more wattery than oil.


Im still pondering if i should replace the head gasket or not, the engine is built in 2011, and i kinda dont want to mess with it, knowing that other than the water on plugs issue, it works perfectly fine.

How hard is it to take the head off, i never did it before.
 

bruceb58

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Re: Volvo Penta 3.0 Oil on spark plugs

Doesn't seem like you need to replace it to me although the low number on #4 is a little worrisome.
 

Walt T

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Re: Volvo Penta 3.0 Oil on spark plugs

Try it with just the manifold. Change the oil then get it hot so any water in the oil evaporates. You may need to change the oil again. I don't know why there was oil squirting out with the water. All I can say is give it a shot.
 
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