Volvo Penta

I have a motor Volvo Penta AQD 41A in my boat, and now I have a problem that
I don't get to identify. - The motor usually works, meantime after some
hours of use, it expels the whole lubricating oil through the breath filter.
I made the test of compression emission opening the cover where the oil is
put, and I didn't notice any compression emission.
I would like somebody to guide myself to I respect, because several
mechanics that I consulted myself didn't give a satisfactory answer.
The apparent causes would be rest in the pistons, but that is not true
because the motor is not with the level of the low oil.
Reply to
Loading thread data ...
Dear Fernando:
There are seals between the oil-and-crankcase-area and internal-piston-space, at the following locations: - pistons seals - exhaust valve seal - intake valve seal - head gasket - oil passages in engine block (and heads)
So piston seals apparently are not leaking.
I don't know how the intake manifold is run on this engine. It sounds to me like either you have: - a faulty intake valve stem seal - a blown head gasket - a cracked block - a cracked head
If it were a valve stem seal, I would have expected the exhaust valve seal to have failed. In inlet valve case, I would expect the spark plug to foul more frequently. In the both valve leaks, I would expect oil smoke to come out. Is there any smoke?
The other posters might be of more help. You are aware that there are oil-filled air filters, right? Does you engine use one of these?
David A. Smith
Reply to
N:dlzc D:aol T:com (dlzc)
"Fernando" wrote in news:
Interesting problem. There appears to be pressure building up in the crankcase over time. This could be a small head gasket leak into an oil passage, a cracked block, or any of several other paths. The difficult part is how the pressure is forcing oil out through the breather rather than just escaping. I don't have any idea of the arrangement of oil level, oil baffels, or breather tube in that oil pan. Boat motion may have something to do with it. I would suggest you take the question to rec.boat for pointers to a solution. Somebody there should be familiar with this particular engine.
Reply to
Charly Coughran

Site Timeline

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.