Rear main seal inserts, do you guys use em

[87owner]

The directions say no to bother, and to use only use RTV. I also have heard lots of stuff about needing that anaerobic sealer. If I were to fill those entire slots with RTV its no wonder some say it will not cure. I only have RTV and I'm pretty confident I can make it work with the inserts and a little RTV. So whats the problem with the inserts.

It reminds me of front and back lower intake to block gaskets. Everyone says to use only a fat bead of RTV instead. I have done it both ways and always gotten it to seal.

 

[BoostKillsStres]

I used black rtv and found my own way of getting it in there w/o a mess. I neatly prefilled the side groves w/ rtv before installing the cap then put the cap in, snugged it up, then used the rtv tube to force more into the groves so it pressure filled the groves and a little came out the sides. I figure as the engine heats up there's plenty of moisture generated to make it cure. I have no leaks in 500 miles so far. That way I didn't have to worry about possible air pockest that would cause a leaking nightmare in the future, I knew those gaps were full.

I tried the rubber plugs but that was just a mess w/ rtv on them and trying to get them in while under the car to make sure I wouldn't have a future leak so ended up pulling them out
HTH

 

[Lee Thompson]

RTV

With eng. upside down, I fill the bottom 1/3 of the groove with RTV and start the side inserts (coated with RTV) in to groove down to the RTV. Install cap and torque to desired value. Then drive insert on down as far as possible. Trim excess flush and insert correct nail. I use a paper thin layer of Loctite 518 gasket maker where the cap mates to the block. I have had great success this way.

 

[S10xGN]

The inserts are difficult to install while laying on your back under the car with oil dripping in your face. I think this is the main reason people prefer RTV. I've not yet done a rear main job this way, so I use the inserts while working an "engine on the stand".

 

[87owner]

is it possible for the entire pan to be leaking like a mother and the rear main be fine. The pan was totally soaked from all sides. The the bolts were barely tight. As the bolts came out the pan just fell like 3/4 of the way off I just had to wiggle it past the pick-up. It had this real thin rubber gasket that just fell off also. There was oil on both sides of the gaskets so It was leaking bad. So far the main area looks dry. I guess I will look it over good to make sure. But should I just do it now that I am in there, or is there alot more work ahead of me. How can i be sure the rear main is not leaking. is that thin rubber gasket a replacement than somebody put in.

 

[salvageV6]

Yes the pan can leak without the rear main leaking.

About 8lbs. on the pan bolts with a new gasket.

Put it on with no sealer gasket to engine block.

If the rear main leaks you can still get back in there with a one week old cork gasket.

Just my .02

 

[87owner]

did you reconmend not putting any rtv on the block side of the gasket so it can be reopened easier, or do you always do it that way?

 

[salvageV6]

Only done 2 so far but both have been glued the night before with skim coat RTV to a spotlessly clean pan.

Cork to the pan and align all the holes and put it upside down to dry or some weight on the surface. Make sure nothing is out of alignment and nothing sticks to the top of the cork either.

No need for goop with the cork to engine surface. Easier to align without it.

Assuming the front of the pan to timing cover is okay and new too.

Not sure if you might need RTV in that area and some cleaning of oil and all.

 

[Woody]

I recently replaced my rear main seal with the rubber inserts as well as a Fel-Pro blue "rubber" type pan gasket. I found a large bottle of anarobic RTV sealant at O'Reilly's for about $6.00........It has been 3 months since I did it and no leaks!!! I had the same problem with my pan bolts........the rears were very loose, hence a lot of leakage, but when I pulled the main bearing cap I found that the old rope type seal had completely disentigrated and the residue had almost completely stopped up my oil pickup screen. I replaced the seal (all Fel-Pro parts) and a new GM pickup screen and tube for less that $70.00........

Good luck!!

Woody

 

[87owner]

just got done. I had to do the whole job anyway. The actual RM-seal was fine but the main cap was leaking on both sides as bad as the pan was. Those slots were filled with this skin colored sealant and no inserts. It had shrunk and pulled away from the sides. I just pulled it out before I even unbolted the main cap. Well I'm glad its done anyway. It went smooth, the pan came right off with no jacking. What pisses me off is the most time was wasted on that stupid clip that holds the tranny lines. It is in a tight spot. Plus it has that kangaroo tail to push it up on its stud. I had no idea what it looked like and could barely reach it.