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Oil coming out of exhaust

D

dtully

New member
I have a crusader 270 which is currently burning about 3 quarts of oil over a 5 to 6 hour cruise at about 2900 RPM's. Both heads and head gaskets were replaced over the past three and four years. The boat sat idle all season last year due to replacing the other engine. This seems to have happened this year. Prior years, the oil consumption was normal. There is no blue smoke coming out of exhaust, but a slight sheen of apparent oil. No sheen from other engine. The engine starts well and seems to run strong. Had done an oil change at beginning of the season and had limited use until recently. No misses or hesitations. There is no evidence of oil leaking beneath the engine. Durning the head gasket and head replacements, there was antifreeze in a few of the cylinders which was cleaned out prior to new head gaskets and heads. This engine does not seem to have an oil cooler, only a transmission oil cooler. Manifolds risers and elbows about four years old but again, no use last year. I am baffled, any input would be greatly appreciated!
 
how many hours are on the engine?

FWC or raw water cooled?

your first sentence says 'burning'; the rest of the description suggests "leaking" - which is it?
 
makomark said:
how many hours are on the engine?

FWC or raw water cooled?

your first sentence says 'burning'; the rest of the description suggests "leaking" - which is it?
Click to expand...
Thanks for the reply...it is fwc. As for hours...I bought the engine from a place called Daddy O's in Pompano Beach Fl (seemingly now defunct). It was purchased as a "new" not rebuilt longblock. There is about 75 hours on engine. I came to find out in short order that it had an automotive distributor which I replaced with (Delco EST marine) about 30 hours ago at which time I replaced the automotive carb with Edelbrock marine carb. Shortly thereafter I did a compression test at which time I discovered a blown head gasket on one side. Replaced the head gasket and head about 25 hours ago and the following year I discovered the head gasket on the other side was bad so I replaced the head gasket and head on the other side of that same engine. About 20 hours on that head. At that time while top end was apart, I replaced all push rods and rocker arms as preventive measure. I believe the engine is leaking oil as there is no evidence of blue smoke during running or start up.
 
with no oil cooler, the only path I can envision for the oil to get into the exhaust is thru the combustion chamber...you said no blue tint to the exhaust so unless you have a dead cylinder, I don't have a viable explanation for you...
 
It does not use PCV valve. Crankcase vent goes directly to flame arrestor without PCV. I did do a compression test yesterday and all 8 cylinders came back with around 180+ psi. I changed the plugs and did an oil change. I'll see what happens from here.
 
Capt Bob...thanks! I did the compression test and all cylinders came back at or aound 180+psi. The old plugs were gapped at .035 as the old ingintion system was prestolite breakerless distributor. I had subsequently changed to Delco EST but never changed the plugs. The gap for ingintion with Delco EST is .045 so I purchased new plugs and gapped them to spec and verified the plug wires snapped on. I subsequently restarted and there was no evidence of raw oil in exhaust. I subsequently did an oil change and will be taking it out Sunday to see what happens. It may be possible that it could have been as simple as an improperly connected spark plug wire and/or improper spark plug gap...fingers crossed! Oddly enough, If I have an oil cooler, I have no idea where it is. There is a crusader transmission fluid cooler (single stack).
 
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