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Old 07-03-2017, 03:43 PM   #1
nheller76
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gear head question

So my friends, here is what i need help with today! I pulled my motor the other day because I had a multitude of leaks and i was tired of trying to find them while it was in the truck. I roll the motor over, pull the pan and find that my rear main cap is chipped on the flex plate side. Not a function problem but it does allow a little oil to seep out, making a mess. Anyone got any ideas about how to fix it without buying a new cap and having the whole thing line board!
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Old 07-03-2017, 07:36 PM   #2
Jake Wade
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Re: gear head question

I don't see where that would cause a leak. You have more than enough gasket surface to seal before it gets to that point. Before reinstalling the oil pan, degrease the main cap gasket surface with brake cleaner and apply a light skim of RTV before laying down the gasket. I prefer the Felpro one piece style.

Last edited by Jake Wade; 07-04-2017 at 09:45 AM.
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Old 07-03-2017, 09:41 PM   #3
smpoulin01
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Re: gear head question

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Originally Posted by Jake Wade View Post
I don't see where that would cause a leak. You have more than enough gasket to seal before it gets to that point. Before reinstalling the oil pan, degrease the main cap gasket surface with brake cleaner and apply a light skim of RTV before laying down the gasket. I prefer the Felpro one piece style.
X2! Don't believe that will cause a problem.
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Old 07-04-2017, 07:29 AM   #4
homemade87
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Re: gear head question

I happen to disagree . It looks like there is some damage in the seal area or close . If it was hit hard enough it could make that seal area out of round enough the seal can not seal proper . Cant see that with the eye . It may have been dropped . Not sure what would have caused that damage .
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Old 07-04-2017, 09:13 AM   #5
oldpurple
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Re: gear head question

As others have said I'm not sure if that would be causing your leak. Could it just be the rear main seal leaking and making a mess everywhere?

If you want to fix it you could maybe build it up with some JB weld and file it to shape once it has cured, but I don't know if that'd hold. It might be nearly impossible to get it clean enough for epoxy to adhere.

I'd also recommend the fel-pro one piece pan gasket regardless of fix.
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Old 07-04-2017, 09:16 AM   #6
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Re: gear head question

That looks like where the oil pan gasket rides & rtv should seal it just fine. The rear main seal is on the inside .
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Old 07-04-2017, 09:34 AM   #7
Desert1957
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Re: gear head question

IMO if the Rear Cap was distorted enough to cause a leak at the rear man the bearing on that half of the cap would be showing wear into the copper. If the bearing looks like even wear on both halves, install the new rear seal and try it.

Or reinstall the cap and bolts. Torque to specs. check the cap and bearing with a bore gauge to be sure.

Don't forget about the little trick of offsetting the seal from the cap line.

Rotate the seal 1/4"-3/8" so that the seal split is different then the main cap split.

FYI on the oil pan , ditch the cork and use the one piece "Felpro" oil pan gasket, NEVER had one leak.
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Old 07-04-2017, 11:54 AM   #8
nheller76
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Re: gear head question

So i figured out what caused it, when i put the motor together i bought a kit that had new bots for my flex plat, when i attempted to use the new bots they bottomed out. I'm wondering if one went far enough to put that divot in it.

I also used the 1 peace felpro gasket but i went through 3 of them because they all leaked. granted i put them in wile the motor was still in the truck and that may have something to do with it.
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Old 07-04-2017, 12:34 PM   #9
Desert1957
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Re: gear head question

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Originally Posted by nheller76 View Post
I also used the 1 peace felpro gasket but i went through 3 of them because they all leaked. granted i put them in wile the motor was still in the truck and that may have something to do with it.

?????? Only use part Felpro #OS 34510T (Shown Below) or Felpro #OS 34500R

Name:  FELPF_OS34510T_P04_TOP.JPG
Views: 176
Size:  63.2 KB

I personally have installed over 20 of these over the years on different engines with zero problems, do not let them sell you any other number. This fits 73-86 SBC
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Old 07-04-2017, 10:58 PM   #10
MikeB
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Re: gear head question

The rear seal from a standard gasket set will probably take care of it with some RTV between seal and rear cap. But a one-piece gasket will do it for sure, and will do a better job of sealing everywhere else, too.
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Old 07-05-2017, 12:52 AM   #11
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Re: gear head question

Quote:
Originally Posted by Desert1957 View Post
?????? Only use part Felpro #OS 34510T (Shown Below) or Felpro #OS 34500R

Attachment 1667174

I personally have installed over 20 of these over the years on different engines with zero problems, do not let them sell you any other number. This fits 73-86 SBC
yeah what he said. Ive had issues with other gaskets. Go to this one, problem always solved.
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Old 07-06-2017, 08:20 PM   #12
nheller76
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Re: gear head question

Hear are some more pictures of it, I don't know why but it was leaking like a bad rear main seal. i know the rear main seal is new and put in right.
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Old 07-10-2017, 10:01 AM   #13
Pontiac1976
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Re: gear head question

I bet oil getting under the seal working out. I would get it welded it not cracked or bent, or just a new one. one less thing to worry about.
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