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Which Rear main seal?

I would just use the "performance" seal. Chevy don't have a problem with rear seals leaking unless they are installed incorrectly or the engine has lots of miles on it with loose main bearing clearances.
 
Brand new block, about 1k miles and I believe the seal is gone... Keep bumping a thread on it but no replies.

Can I drop the tranny and start the motor? I could then get a better look at what's throwing the oil on to both sids of the motor and the header.

It was odd too because we just changed the oil, and the oil coming out was black as hell. Felt like i was running under half power too.
 
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MrArmyAnt said:
Brand new block, about 1k miles and I believe the seal is gone... Keep bumping a thread on it but no replies.

Can I drop the tranny and start the motor? I could then get a better look at what's throwing the oil on to both sids of the motor and the header.

It was odd too because we just changed the oil, and the oil coming out was black as hell. Felt like i was running under half power too.

Yes you can start the engine with the tranny out but make sure the engine hasn't tilted back too far and allowing the fan to hit the shroud.

The only thing that makes oil black is fuel. If you only have 1k miles on this engine and the oil is black you have a problem somewhere that needs to get fixed quick.
 
throwing oil on the engine? Rear main seals usually just leak and seep down the oilpan. Would have to be PISSING to do that, and you would have to not be running an inspection cover.

What was your break in procedure?
 
Oil was coming down the oil pan, very quickly. Oil was hitting the tranny and being spun onto the headers. break in procedure was drive it around for the first 500 miles. Would the rear main seal being gone account for the fact I can barely get it rolling from a dead stop?
 
not at all. shouldn't do a thing but leak oil.

I ask, because last mystery oil leak I had was a chunk out of a piston. Instead of compressing, it was pushing air into the engine, then out everywhere it could leak. Not trying to scare you, but a compression check might be in order as well as a rear main seal.
 
Motor is still under warranty. They keep trying to refuse to work on it saying "it isn't driven like a honda" Everytime I say that I want to hit them with my farmers jack.

Thanks for the help. I guess I'll just have to drag it up there, and get them to look at it.

I'll most likely have to fix this myself, can't afford their labor, I need to learn anyway. If I need to replace the pistons, are there any that will add a little power but not be a whole lot more expensive than stock? This motor was also a reman, I wonder if maybe they missed something. Guy said the motorshop it came from in Dallas was reputable, city motors.
 
Also, somehow someone came to the conclusion it might have been the transmission, the mounts were loose and it jacks around. Someone thought it might have been it hitting the rear of the motors screwing with the rear main seal, or it was tranny fluid, which is why it was dirty and had no power (which seems to be one of the dumbest explanations of no power I have ever heard). The jerking of the tranny though does feel like it might be a cause, because it will pull hard, and there is a crack in my bellhousing.
 
I used the performance seal on my 6.2L diesel (the alternative was a rope seal :doah:).

I've also run it without the trans attached. I did prop a jackstand and a chunk of wood under the oil pan so that the engine didn't tilt back and break off the oil pressure sender.
 
i have less than 1000 miles on my new GM crate motor...i get oil like crazy out of the back of my intake manifold....it's seeping down the block and down onto the trans and then to my driveway. not enough RTV when i installed the manifold. my bad. also, it could be spraying out of your oil press. sending unit....when we first primed my motor i forgot to tighten it down...and oil went EVERYWHERE!!!!!! just my two cents.
 
01maroonz71 said:
i have less than 1000 miles on my new GM crate motor...i get oil like crazy out of the back of my intake manifold....it's seeping down the block and down onto the trans and then to my driveway. not enough RTV when i installed the manifold. my bad. also, it could be spraying out of your oil press. sending unit....when we first primed my motor i forgot to tighten it down...and oil went EVERYWHERE!!!!!! just my two cents.

Do you have a loss in power though?
 
no, but it is possible that they are not related....i did have loss of power, but not from that...it was from my timing being off a bit.
 

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