Blew a seal last night. Say what??

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Hevchev

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Hey all new to square bodies. I recently picked up a 78 k10.

After a short drive 5-10 minutes the bell housing and everything behind it is covered in oil from the wind. The oil pan stays pretty dry. It can lose a quart or more within a few minutes.

Any tips to confirm it is the rear main? Or any other spots to look at before I start the tear down.
 

PrairieDrifter

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Remove the inspection cover and look inside of the bellhousing. It should be coated with oil if it’s leaking that much, it should be dripping out honestly.

If it’s decently dry on the bottom it’ll be your valve cover gaskets or your intake gaskets.

Spray a bunch of degreaser over the motor and trans, of course be careful around stuff like the carb and distributor as well as with water wash it all down then run it and search everywhere to see where the oil starts leaking from.
 

Charlie

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:welcome:
 

bucket

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Blew a seal... Reminds me of a song.

Seriously though, besides the rear main, the oil pressure sending unit up next to the distributor could be puking oil too.
 

Hevchev

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I will take a look at those things tomorrow.

Thanks guys
 

PrairieDrifter

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Or the distributor gasket even
 

Hevchev

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Haha good video haven’t seen that.

At least part of it is coming from the fuel pump that I recently replaced.

The pump came with two thin paper gaskets is there a better brand out there or rtv it?
 

bucket

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The paper gaskets have always worked for me. When you replaced the pump, did you put the short bolt back in the hole on the front of the block? The one that you remove to use a longer bolt in the hole so the fuel pump pushrod doesn't fall out.
 

71RAT

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Hey all new to square bodies. I recently picked up a 78 k10.

After a short drive 5-10 minutes the bell housing and everything behind it is covered in oil from the wind. The oil pan stays pretty dry. It can lose a quart or more within a few minutes.

Any tips to confirm it is the rear main? Or any other spots to look at before I start the tear down.

Oil pressure sensor, back of the block
 

Kyle89

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Welcome to the forum good luck with your problem... I had a 88 that it turned out to be the rear part of,the intake between the block and intake... Bought it from a guy he put a new intake on and didt have a proper seal and thought he blew the rear main... Bought the truck for 400 bucks put new intake gasket set on it and drive it for a year before selling
 

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