Crankcase pressure? Venting issue?
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Crankcase pressure? Venting issue?
Hello... So just bought a clean 69 genny shovel.it has a s&s oil pump and looks like a recent rebuild. Starts easy, compression at 110 each cylinder.good oil pressure. Problem I'm having is a white smoke at idle,a steady stream of oil from the case halves near the rear motor mount.and a constant oil drip from breather tube. Is this a breather timing issue?i feel something is causing excessive pressure or over filling crankcase with oil. I put new check ball and springs in oil pump with no affect. Thanks in advance,bill
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From: la la land jerzey
you have a sealing issue - rings maybe the gaps all in allign instead of staggered - it was honed incorrectly and now the engine is not sizing when hot and allowing oil to by pass
if you do a wet compression and the static compression - the 110 i think you said stays the same or just moves up a bit than for sure your piston / cylinder seal is at issue
if you take it apart have some one check the heads that really knows what he is looking at, as oil seepage around the guides can also do that -- and the valve seals and valve to valve guide clearance Must be checked
if you do a wet compression and the static compression - the 110 i think you said stays the same or just moves up a bit than for sure your piston / cylinder seal is at issue
if you take it apart have some one check the heads that really knows what he is looking at, as oil seepage around the guides can also do that -- and the valve seals and valve to valve guide clearance Must be checked
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From: Cental, MI
Nah...Sorry to say ..depending how old that S&S oil pump is. They had some quality control problems for a time. Not unusual for a brand New S&S oil Pump to exhibit Sumping Symptoms...
I ...and some folks I know Have them...My next Rebuild will have an OE pump.
Edit; If I run mine for a time...it clears up. But, If I let it set for any time, It acts like an old worn out Sumping Issue..."Sigh"
I ...and some folks I know Have them...My next Rebuild will have an OE pump.
Edit; If I run mine for a time...it clears up. But, If I let it set for any time, It acts like an old worn out Sumping Issue..."Sigh"
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Thanks for the quick reply.couple days ago I opened up the primary inspection cover and it was full of oil, I mean almost to the top.so I checked the oil tank and it was nearly empty.so I pulled the primary oil return line" it goes to the block directly to the left of oil pump" and it was pushing oil and air out. I thought the port should suck oil back from primary?at that point I has zero oil coming from the crankcase breather. I isolated the primary, refilled oil tank. Now it has more white smoke at idle,the case leak was amplified, and a constant drip from breather.ill take the oil pump off and throw a rebuild kit in. Ill shoot some oil in cylinders and see if anything changes.thanks
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From: la la land jerzey
If your problem was sumping than maybe the oil pump is the issue BUT that is not what you have AS you have found out -- your breather is not sucking the oil out of your primary as it is back filling it instead - so removing the cam cover and looking at the condition of the breather valves bore, is ONE the first thing's to do as well as checking the compression static, to insure your piston to cylinder seal is good - if it is than go after the breather
the oil pumps return has NO ball check and OR a spring, it is free flowing to return any oil it sees directly to the oil tank Via a cooler if you have one -
oil pump sumping is in fact the gravity ball and spring to its seat, IT is not perfect and removing the oil pump and using very fine valve grinding compound to re lap the ball ( we made a tool out of an old ball and a 1/4 inch shaft welded together ) to the oil pump body in Most cases fixes any pump as they all do that at some point - and that has nothing to do with the breather not sucking oil into the cam cover from the primary, this is my take someone else might have a different idea but this is mine -- jz
the oil pumps return has NO ball check and OR a spring, it is free flowing to return any oil it sees directly to the oil tank Via a cooler if you have one -
oil pump sumping is in fact the gravity ball and spring to its seat, IT is not perfect and removing the oil pump and using very fine valve grinding compound to re lap the ball ( we made a tool out of an old ball and a 1/4 inch shaft welded together ) to the oil pump body in Most cases fixes any pump as they all do that at some point - and that has nothing to do with the breather not sucking oil into the cam cover from the primary, this is my take someone else might have a different idea but this is mine -- jz
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So today I removed both cylinders and heads. Front exhaust valve guide is leaking oil badly into the cylinder. Both pistons are std bore. Looking into the cylinders the pistons had a large gap between the piston and cylinder as if the pistons were not fitted correctly. Also noticed slight rubbing on the skirts.Would this be causing a huge blow by affect? Pressurizing the bottom end making oil puke from the breather and leak from my case halves?im thinking I'm on the right track now.i did find I have s&s rods 7001&7002 so someone has done some bottom end work.
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From: la la land jerzey
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From: Michigan 15 Minutes East Of Hell
Along with the pistons being "too loose" you would do yourself a service by checking the breather gear, ( bore, screen, gear and clearance [end to end] ). Also, many shovels have a very small rough cast window that the breather gear uses. Opening that window and cleaning up the area will help immensely. I had a picture but can't find it now of how to size it. You might find "visuals" through S&S. I did mine when I put the stroker kit in it.
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Thanks Larry. I pulled the cam cover off and removed the breather. The screen was clear of any debris. Also all marks lined up.my guess now is the bad piston and ring combo is blowing by and causing crazy crankcase pressure. Would you split the cases to reseal? Or after I correct the top end issue the case leak will go away?