My fricken rear main seal just popped out!!! Argh took the car to get some smokes around the corner and when I got back and parkec I had a gigantic oil leak on my driveway. I started the car and took a looksie underneath and there was a **** load of oil pouring out of my bellhousing. Now I have to remove the tranny again and replace it. Sigh, I thought I had it in correctly....


Ugh im not looking forward to that again. anyone got advice on how to put the seal on correct let, I just lined it up center and plugged it up by hitting it with a rubber mallet until it was sealed all the way, I didn't use any sealant, just put it on. Thought that was how you were supposed to do it. Anyone got some tips?

 

I know its early, but im about to get started folks, need to know the proper wait to seat that rear main seal with the engine still in the car .

 

This info is from the Helm manual. All it says to do is to put engine oil on the inside bore of the seal. (Doesn't say anything about a sealer on the outside).

The seal has a spring around one end and a dust lip on the other end. The spring end of the seal goes into the engine first.

RBob.

 

Ok, not quite sure I understand or maybe im being too cautious.... Allow me to MS paint something real quick.... Just pretend that this is the side with the spring that is housed inside the seal. The other side the spring is not visible. Which side goes into the engine?

 

See attached. . .

RBob.

 

When I have replaced mine on the 3.4's, I cleaned surface area real well.
REAL WELL
Scapped, etc.
First time I used nothing as sealant or lubricant-drove it in.
Rear Main Seal was replaced when the tranny went after the Firebird 3.4 swap.
THIS 3.4 Blazer TIME, same formula. YET, I added/used gas-a-cinch around outside & inside of metal surface area.
Seems to be better seal.
Best thoughts!

 

just making sure, but are you sure its the rear main and not the cam plate seal above the rear main? or the dist o-ring? just want to make sure.

 

Im positive this masive leak is the rear main. However, the cam plate could possibly have a small leak also. I already checked the distributor and its fine.

 

Ok, its all off again. I just checked the seal and to my surprise its not the seal . I started checking around the area and near my oil filter I saw a wire hanging and took it off and realised it was broken. I take it this is your oil pressure sensor? How do I replace one that has been broken? Anyone know the part number.

Also I noticed I have a little bit of an oil stain below the distributor by putting my finger there from under the car, but when i look from the top, the distributor looks clean (the bottom, not the top :P). Where is this infamous O-ring gasket and how hard is it to replace? THanks.

 

as far as the oil pressure gauge goes, its just threaded in. get a socket and take the old one out and put the new one in. the distributor o-ring... mark where the dist. is. put a mark on the dist shaft base and on the block to mark it so when it goes back in the timing is accurate. pull it out, replace the o-ring. KED85 also recommends getting a 350 dist gasket to aid in sealing. reinstall it and just to make sure, id say get a timing light and reset your timing. i havent actually done it myself yet, but ive read and heard enough on here to say that i should be right on about what i just said. im going to have to redo mine soon too. and if you have the dist out, you might as well do a rebuild on it. it only costs about $20, $30 at most. do a search for the rebuild and it will tell you all the stuff you need and how to do it. good luck dude!!

 

I totally agree!
Seriously, lots of little things done now ensure long time preformance gains & happiness.
Have ya changed the timing chain?
How many miles on the engine?
When ya get the oil pressure sender, make SURE
it reads to 80 POUNDS.
V6 pressure is read that high.
The oil filter housing can also leak, too.
Replacing that filter housing gasket is NOT fun!

Yes a small block chevy distributor gasket fits prefect & ensures zero oil leaks.
I now add, tho, get a new o-ring, too.
Both items will run ya about $2!

 

Ok, whats the oil pressure sensor called? So I know what to get at O'reiley's instead of "Hi, I need an oil pressure gauge thingy that goes near my oil filter ". As for the distributor, is it easy to pull off?

 

I would think you could just tell them you need an oil pressure sending unit.

Thats all my parts store needed to hear when i had that problem.

 

Do a search for my Distributor Rebuild article thread.
It's easy, really.
Ya need buy a few new parts, but the results are really worth it.
Cost can run to about $50 in parts.
Rest is brake cleaner fluid, sandpaper and a good eye.
OH Fresh Axle grease, too!
This is an easy project, but again, detailed.
You solve oil leak at same time so ya win pretty well.
Oh the gain in pep can't be beat, either.
This project is a start for complete ignition system rebuild.
If your current engine eventually dies (due to age milage), all this rebuilt work swaps to a new long block like a 3.4!

 

Well crap, O'reiley's and Autozone don't carry the oil pressure sending unit for our MPFI's. Ugh I didn't want to but gotta order it I suppose.