Oik leak possibilitys
Thread Starter
Racer
Joined: Feb 2012
Posts: 256
Likes: 30
Oik leak possibilitys
What are the possible oil leak sources from rear of BBC? From inside the flywheel housing,Aside from main. Or is main the only possible oil leak source? My oil leak come directly from the center of the pan.
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
If it's a Muncie 4 speed and you overfill it, it will leak out the front seal and drip down at the bottom of the bell housing.
Melting Slicks
Joined: May 2011
Posts: 2,753
Likes: 119
From: Springfield Missouri
rear main seal, or small plugs at back of cam, distributor seal gone, valve covers(most likely)gaskets(easy fix). can you work on the car or do you have to take it to a mechanic??? could be the oil pan leaking, have you tried to tightening the bolts(easy does it, not too tight where you break them)
Last edited by lvmyvt76; Dec 15, 2016 at 08:05 PM.
Melting Slicks
Joined: May 2011
Posts: 2,753
Likes: 119
From: Springfield Missouri
pull transmission from motor so you could see. usually the cam plugs don't leak, unless someone has been in the motor and not put them back in correctly. did you check the dist seal??/ valve cover gaskets?? pan for being tight?? these are more apt to be the problem. are you saying the oil is dripping off the bottom center of the pan , or is it running down the back of the motor and to the center of the back of the pan??? is the a cover on the bell housing on the bottom?? check behind the dist for oil up there, if there is oil, then the leak is high and going down. remember that when you drive the car, the oil will be pushed to the back of the engine and run down to the bottom.
Last edited by lvmyvt76; Dec 16, 2016 at 08:18 AM.
Thread Starter
Racer
Joined: Feb 2012
Posts: 256
Likes: 30
Oil is dripping from the center of the pan. I had the motor rebuild with the original pan. I
Spotted the leak after first start up so I replace the gasket but that pan was so stuck on the block it gave me doubts. I used a 4 pc seal with rtv on both sides (allowing the rtv to dry a bit befor install)and it still leak. Then I replace with a Felpro one pc, dry install and it leak. Then I got a new milodon pan with a moroso 1pc composite seal, dry install and it leak, but not as bad. So I went back and used rtv on both sides and it's better than ever but I still see a drop from center of pan.
I don't have the tranny dust cover but I just ordered it. Everything you mention is dry. The Dist seal is damp and does have a trail that ends on the casting Numbers. But it's to dry to lead to the oil pan.
I believe it's the pan because the leaks were really really bad with the original pan and the Felpro 1pc. With the milodon pan and moroso 1pc I get 2 quarter size drops.
Spotted the leak after first start up so I replace the gasket but that pan was so stuck on the block it gave me doubts. I used a 4 pc seal with rtv on both sides (allowing the rtv to dry a bit befor install)and it still leak. Then I replace with a Felpro one pc, dry install and it leak. Then I got a new milodon pan with a moroso 1pc composite seal, dry install and it leak, but not as bad. So I went back and used rtv on both sides and it's better than ever but I still see a drop from center of pan.
I don't have the tranny dust cover but I just ordered it. Everything you mention is dry. The Dist seal is damp and does have a trail that ends on the casting Numbers. But it's to dry to lead to the oil pan.
I believe it's the pan because the leaks were really really bad with the original pan and the Felpro 1pc. With the milodon pan and moroso 1pc I get 2 quarter size drops.
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Le Mans Master
Joined: Oct 2006
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
In addition to the cam plug, there are 3 pipe plugs on the back of the block. 2 close to the cam (lifter galleys) and one above and inboard of the oil filter pad- all are behind the flywheel/flexplate.
Melting Slicks
Joined: May 2011
Posts: 2,753
Likes: 119
From: Springfield Missouri
ok. oil in center of pan, coming from where? side of motor or from top of oil pan?? if top of oil pan, could also be from the filter area?? oil sending unit? oil filter seal bad, drain plug on pan? if it is leaking from above the pan, then it is not the pan. clean off everthing and find where oil is coming down from? back of engine? then rear seal if nothing is coming from top of engine, intake gasket in back leaking?? engine been overhauled?? then it could be the the intake valley gasket. very common if not kept in place when intake was put on. who did the overhaul??
Last edited by lvmyvt76; Dec 16, 2016 at 09:57 PM.