oil leak

[10ih66]

I have a IH 504 diesel that was blowing oil out of the crankcase breather so I rebuilt it thinking it was the rings,but after the rebuild it runs fine but once it warms up and I put it under load it blows oil out of the crankcase breather still.Any ideas?

 

[DJ54]

How complete of a rebuild..?? Just re-ringed, or sleeve & piston set? If just re-ringed, they may not be seated/sealed yet, still causing blow by. The only other things I can think of would be, #1. A valve not completely seating, due to a burned valve, or weak valve spring, and compression coming up passed the worn valve guides. That in turn would pressurize the crankcase, via the valve cover/oil return ports. #2 The head is warped, or deflected away from the top of the sleeve enough, the head gasket isn't sealing on the oil return side.

Have you looked in the radiator to see if bubbles appear there..?? Just be careful to watch for after boil if you haven't..!! That much compression loss I'm thinking should show up in the coolant system too, if there are problems with the head, and/or head gasket itself.

If no bubbles in the radiator, believe I'd pull the valve cover, and listen for a compressed air leakage. It'd probably blow some oil on top also. Just don't put your hand over top, use a stick of some sort, and keep your hands away. With near a 18:1 compression ratio, you're dealing with some serious pressure.

If nothing shows on top, I'd guess rings not seated/sealing for some reason.

 

[DJ54]

Also, did you happen to check for the tops of the cylinder liners for equal protrusion..?? I checked the parts page for that engine, at least on the earlier models, shims are available to get the liners at the proper protrusion, and equal to each other.

I'm just assuming the info for proper protrusion height above the top of the block, and variance between all 4 would be in the service manual.

 

[10ih66]

Also, did you happen to check for the tops of the cylinder liners for equal protrusion..?? I checked the parts page for that engine, at least on the earlier models, shims are available to get the liners at the proper protrusion, and equal to each other.

I'm just assuming the info for proper protrusion height above the top of the block, and variance between all 4 would be in the service manual.

The liners are egual in height and in spec. with the service manual.As far as the rebuild it was a complete in frame overhaul.The tractor did this before I overhauled it so I thought it was the rings but apparently that was not the problem.

 

[DJ54]

Did you do anything to the head..?? Lap valves, complete valve job, check for weak/broken springs, etc..?? With new liners (thought about it afterwards, maybe one of the liners may be cracked) seems out the top is the only place you could be losing that much compression.

The only other reason I can think of would be too much oil in the crankcase. Or only does it on a really steep incline where the oil may slosh up on the crankshaft. I'm pretty well assuming you're filling the crankcase by the amount of quarts required, and not by the dipstick. A PO could have changed it out with a shorter one.