283 Rear Main Cap Blues

[bhc41051]

I finally broke down and tried to fix my rear main leak, 62 K10, 283 all stock. I don't know what happened to my cap but this has to be the cause of the leak right? Can I change the cap without line boring? Truck doesn't do any work, no mud bogs or pulling a track hoe through the Rockies.

[imjeff]

I wouldn't replace a cap without line boring. Finding one even close enough to appear ok is a long shot. A line bore isn't that huge of a deal.

[GASoline71]

Finding another cap for a small journal 283 might be a bit harder than it used to be. But the cap will have to be as close of a fit to the original, before most machine shops will even consider a line bore.

Gary

[Marv D]

Ya know I'm looking at this and thinking if the pan gasket is in place, and properly glued to the cap,,, why would this be an issue???
I can't see it well enough to tell but is this a neoprene seal or the old rope seal? Don't get me wrong,,,, I don't 'like' what I see here, but not so sure the fracture is causing a oil leak. (or any other problem for that matter)

[Captainfab]

I have to agree with Marv. That doesn't look good but I don't think that is causing an oil leak unless there is more extensive damage than what we see in the pics.

[imjeff]

Looks like someone got mid evil on that cap with a hammer. I agree it looks like it will seal. Might have to file some of that displaced iron out of the groove.

[bhc41051]

Thanks for all of the replies everyone, I put everything back together, I rotated the new rear main seal so the ends weren't even with the cap and a very thin layer of sealer on the flats of the cap. Replaced the pan gasket with a one piece. I started the truck, no leaks for the first two minutes or so. Then it started leaking pretty bad, drop a second or so. but then it stopped and hasn't leaked a drop since. Floor is dry this morning. I'll keep my fingers crossed.

[GASoline71]

Pan rails flat? Even with the new 1-piece gasket that has the steel grommets to protect from over torqueing, old warped pan rails will still leak. Did you straighten out the rails of the pan first?

Also... many a valve cover, rear manifold seal or an oil pressure sending unit leak has been mistaken for a rear main leak.

Just trying to cover all the bases here.

Gary

[burnin oil]

Not all one piece pan seals are the same. The first one I used leaked like crazy. The second one sealed pretty good other than a tweaked pan rail so that wasn't the gaskets fault. A quick whack with a hammer fixed it. One of the best investments I have made was pan studs. Makes it so much easier to install the gasket while the motor is in the truck. Hopefully you put a dab of sealer at the block to cap sealing surface and insured that the gasket fully seated in the registers for the front and rear seals. I also agree that the main cap should not be an issue.