Rebuilt burning oil

[jimmbo]

Is the oil getting into the cooling water, or is it just getting into the exhaust and then mixing with the water? Bad/missing valve seals on the exhaust valves?

Taking a 3rd look at the video. It looks too black for oil, more like carbon from a very very rich carb mixture. Is the choke opening fully? Float way too high?
When it belches the black stuff, is there a smell?

 

[westriverboater]

Thanks 89retta I like guarantees! I'll pass along your suggestion.

 

[westriverboater]

jimmbo, checked the choke and it seemed ok. Not sure where the mixing is happening but your right it is more sooty than oily and very little smell but with the heavy oil consumption is has to be oil based. If you notice it seems to belch after the acceleration - someone suggested maybe a vacuum problem.

 

[tpenfield]

I would not continue to mess with the engine. Sure seems like the rebuilder has missed the mark somewhere.

 

[89retta]

https://www.marinepartseurope.com/en/volvo-penta-explodedview-7745510-21-21921.aspx . I'm thinking #24 or 26 is messed up. And the oil is filling up your bellhousing and leaking into your bellows. Only way to explain losing that much oil

 

[jimmbo]

It doesn't look like it is trying to burn the oil, unless you aren't showing all the mosquito control smoke coming out of the exhaust outlet.
The sludge occurs when you quickly close the throttle? If so, that's a clue. High manifold and cylinder vacuum. Normally I would say valve guides and seals, but this time I'm thinking oil control rings on the pistons are, not installed correctly or missing

 

[89retta]

It doesn't look like it is trying to burn the oil, unless you aren't showing all the mosquito control smoke coming out of the exhaust outlet.
The sludge occurs when you quickly close the throttle? If so, that's a clue. High manifold and cylinder vacuum. Normally I would say valve guides and seals, but this time I'm thinking oil control rings on the pistons are, not installed correctly or missing

The guy who rebuilt it might have put the oil rings on upside down. But I think the OP said the plugs look good

 

[jimmbo]

Time to put some clear hoses on the cooling system to see where/if the sludge is in the cooling system

 

[alldodge]

Don't see any way for oil to get into the water jacket and then out the exhaust unless there is a crack in the blocks oil passage which passes by a water jacket, or an oil cooler (which appears you do have) There is no seal that will allow oil in and keep water out.

Would sure like someone to explain how any seal will allow oil into the water jacket and keep water from getting into the oil

 

[jimmbo]

If it has an engine oil cooler, oil could get in the water without water getting the the oil. Oil pressure is higher than water pressure.

 

[westriverboater]

Thanks All! Into the shop tomorrow we go. I'll pass along the constructive comments from this forum and will update when it's fixed, as this doesn't seem to be a very common problem.

 

[89retta]

Any updates ?

 

[westriverboater]

UPDATE: Engines was pulled and taken apart. Mechanics diagnosis was a porous block, not really sure what that means but he also said rings did not seat - probably due in part to the thermostat not allowing engine to get up to temp. Looking for a new block as we speak.

 

[alldodge]

porous block

Have head that happening with aluminum but not in cast iron. I'm sure it can happen but wonder why it was not caught after the block was machined and then inspected prior to assembly

 

[89retta]

I've never heard of any of those causing such a high oil loss. I call BS on him and he's making excuses for his poor work. Personally I would be looking for a different mechanic.

 

[tpenfield]

"Porous engine block" . . . that is a good one. I'll have to keep that one in my repertoire of excuses for when I really mess something up.

 

[Maclin]

MAybe he said Poor Us