How likely is an oil leak from a head gasket?

[Gregski]

Truckers

Having replaced the intake manifold gasket three times now in order to stop the leak coming from the rear of my 350 V8 engine block right above the bellhousing or there abouts, I am beginning to wonder if that may not be the culprit or the only source.

So how likely is it for the head gasket(s) to leak oil back there in the rear of the engine?

I also recently replaced the rear main oil seal as well as valve cover gaskets twice and the oil pan gasket.

the oil drips from the bottom most part of the bell housing where you bolt the fly wheel inspection cover to it, naturally it follows the contours to the lowest point

[kelsfine69]

Not likely. Could be the cam plugs? Oil pressure sender? Distributor gasket?

[Bigstevex4]

Water yes oil not so much. But stranger things have happened.

[enaberif]

Distributor gasket is a big one a lot of people forget about.

Did you use RTV or gaskets on the china walls?

[1970pelle]

I just pulled the engine out of my 1986 with its stock 5.7L. I had found it pouring from the right rear head gasket area. When I removed the heads I found the OEM metal head gaskets rusted and eat away in the area's of my leaks. Now my truck has a bunch of miles. As far I can tell by the records left in the truck when purchased. The engine has 235,000 miles, and was only smoking at start up and had just started to leak oil when running. But needless to say the engine is finished. I have my own thread started. But yes its possible.

Ken

[enaberif]

Originally Posted by 1970pelle

I just pulled the engine out of my 1986 with its stock 5.7L. I had found it pouring from the right rear head gasket area. When I removed the heads I found the OEM metal head gaskets rusted and eat away in the area's of my leaks. Now my truck has a bunch of miles. As far I can tell by the records left in the truck when purchased. The engine has 235,000 miles, and was only smoking at start up and had just started to leak oil when running. But needless to say the engine is finished. I have my own thread started. But yes its possible.

Ken

If oil can bypass the headgasket to leak out of the truck I'm going to say you got much worse problems like worn rings.

[Gregski]

Originally Posted by kelsfine69

Not likely. Could be the cam plugs? Oil pressure sender? Distributor gasket?

Thanks, got new distributor gasket on there, looks dry. The oil pressure sender is clean and dry at the base too. Where are the cam plugs?

[craig113]

Looks like the freeze plug.... one above the crank

[craig113]

And that looks dry to me.. I would drop the oil filter and oil filter adapter and replace the paper and rubber gasket between the block and the adapter. Wind will blow the oil back and follow the oil pan and drip off around the crank and into the bell housing.

[1970pelle]

Originally Posted by enaberif

If oil can bypass the headgasket to leak out of the truck I'm going to say you got much worse problems like worn rings.

NO just old rusted metal head gaskets that had long past done there best. My truck did not smoke when running. Only at start up every once in a while, sure sign of valve stem seals or valve guide issue.

Ken

[enaberif]

Originally Posted by craig113

And that looks dry to me.. I would drop the oil filter and oil filter adapter and replace the paper and rubber gasket between the block and the adapter. Wind will blow the oil back and follow the oil pan and drip off around the crank and into the bell housing.

There shouldn't be a gasket there at all. The rubber seal on the oil filter should be doing the job of keeping any oil from leaking.

[Titomars]

Head gasket leaking oil? Not likely. In following your threads I would say it is still your intake end seal giving your problems. Are you still after 3 times assembling your intake without end seals of any kind? If so, why not try it with end seals. Here is how I do intake gaskets and I have yet to have one leak.
First a trusted quality gasket set is needed. I like Fel-Pro. You will also need a can of Permatex red high tack spray gasket sealer. Clean surfaces as usual nothing fancy. I use a razor blade, it's not brain surgery. Take the side gaskets and both cork end seals lay the on some old cardboard and spray them with a good heavy coat of the Permatex. Let dry (about 15 mins) Then flip the gaskets and do the same on the other side and let that dry. Rubber ends seals go on dry no sealers of any kind. Now take your RTV and apply a 1/4 inch bead at the 4 joints where the heads meet the block. Set in your side gaskets and line up. Set in your end seals and line those up. With rubber end seals you set the end seals first then the sides. Take the RTV and apply a 2nd 1/4 inch bead at the same corners where the gaskets all meet. Now put away the RTV! Set your manifold the check your end seals to make sure you did not move them. When satisfied start all your bolts. slowly tighten 2 opposing bolts. I do 2 center ones alternating till the bolts are snug to about 15 ft lbs. the idea here is to clamp the manifold down evenly and vertically. Now I recheck the end seals. if they have not moved you can tighten up the rest and torque as needed.

[beamn7]

How about the fuel pump mounting plate to block gasket and/or the fuel pump to mounting plate gasket? Seen them leak and the oil blow back while driving and drip off the inspection cover....

[king-918]

I have seen oil leak from head gaskets lots of times, I also work on cars for a living