Rear main seal installation

[cwmcobra]

Any tips on installing the rear main seal?  I'm having a bad go trying to get the side seals installed correctly.  The pins that look like finishing nails are not going in without bending, so I can't get them properly seated to support the seals.  Would I have better luck with the soft side seals?  I'm using Fel-Pro black rubber seals.

Thanks,

Chuck

[sjfd04]

Are you using the 2 piece seal made for the v-6 engine?

[cwmcobra]

I'm using the two-piece neoprene seal around the crankshaft.  What I'm having trouble with is the neoprene side seals that install into grooves on the sides of the rear bearing cap.  I've lubed them with lots of slippery stuff, but when I try to get the steel pins fully inserted, there is too much resistance and they just bend.

Installation instructions I've seen talk about two types of side seals; soft (orange color) and hard (black color).  I'm thinking I should try to find a set of the soft orange seals, but also can't believe that the black ones don't work.  Me thinks I'm missing something.....

Chuck

[sjfd04]

I would contact this guy, he seems to be one of the Nailhead experts:


http://centervilleautorepair.com/seals

[cwmcobra]

Yep, Russ is one of three Nailhead guys that I trust.  I'll probably call Carmen Faso tomorrow since I bought my parts from him.  Thought maybe someone here would have some experience to get me going.

 

Chuck

[Brian]

Chuck,
  I put black RTV all over the side seals before I put them in on the 401 in my car last year.  The RTV acts like a lubricant while still wet, then seals it all in tight when it dries.  The nails went in hard, but they went all the way in.  I used fel-pro gaskets on the entire engine with the exception of the head gaskets where I used factory style beaded-steel gaskets. 

[cwmcobra]

Thanks Brian.  RTV is about the only lubricant I haven't tried.  I saw it recommended on another forum (Y block Thunderbirds), but opted to try a couple of other lubes first.  Did you also RTV the base of the rear cap at the block?  And did you bottom the cap with the seals inserted all the way before driving the pins in?

[Brian]

Yes, I put a skim coat of RTV on the surface where the cap bolts to the block--most of it will squeeze out when you torque it, but it keeps oil from seeping out between the cap and the block.  On a 300 engine, I usually torque the cap, then put the seals on the sides, but on the 401 they were so tight I couldn't get them to go all the way in with the cap installed, so I had to put them in the groove on the cap, then install the cap.  It is tricky getting them to stay in place and go all the way down while you install the cap, so it will take some patience.  If the nails won't go all the way down, I would just trim them off flush.  If they won't go all the way in, it is because it is too tight in there, which means it is sealed just fine--especially with having RTV all over the seals when you put them in.

[cwmcobra]

Thanks Brian.  I'll give it a go again tonight.  I've experienced that "trickiness" of keeping the seals tight to the bottom while tightening.

Chuck

[cwmcobra]

Got it.  My solution was a combination of Brian's advice and that of Carmen Faso today.  Now to start stuffing pistons!

[bobbybuick]

Neoprene seals are great if the seal area of the cap is exact to the crank center .However none of them are ever.After line boring and machine work it might work some of the time .Why do you think the factory used Rope seals its because they will move.After fighting my Pontiac with many different rope seals and the BOP neoprene seal ...i fixed it with BEST Gasket  rope seal They Work !.My poncho NO LEAKS .so when i build my nailhead no BOP for me i used this no leaks IM SOLD 2 for 2 http://www.bestgasket.com/engine_catalog_years.asp?YearsCID=1957-66,%20364-400-401-425.......[597]