Rear Main Seal?

[scojack_2001]

How hard is it to replace? I have the new FelPro neoprene rubber one along with everything else to do the job. Also will be doing a timing chain at the time. Valvesprings will have to wait.

I have access to a lift and any tools I'll need.

So how hard is it to do in the car, without removing the trans?

Any help appreciated.

Scott

 

[KWIKR 1]

you can take this info for what it's worth . Last week I picked up my new short block from a very reputable builder in the Toronto Canada area . we got on the topic on rear main oil seals for Buick V6's . and he said alot of "you Buick V6 guys" are making a big mistake going with a neoprene type rear seals on the stock cranks . He's refering to stock cranks that have the "knurling" on the rear of the crank . He said the best seal for this type of application is the stock type rope seal that GM orig put in these engines . He uses neoprene rear main seals ONLY on other stock or aftermarket cranks that have the machine polished surface rather then being knurled .

 

[TurboCrazy]

Sealing rear main for the newer guys

I have to disagree. I have rebuilt over a dozen TR motors. All have had stock cranks with neoprene rear main seals and never a leak. These motors have run anywhere from low 10's to high 12's and some have high miles on them, now with no problems or leaks. If it is a rebuild, I prefer to have the seal surface belt polished to eliminate irregularities and sharp edges. I have however, replaced the stock rope seal with the neoprene seal and had no problems. I do not use the side seals and pins. They will leak. Clean all surfaces really well and then squeeze RTV into the side slots until it squeezes out everywhere. Then take pipe cleaners soaked in water and shove one per side, ino the RTV in the side slots. Clip off the excess pipe cleaner and smooth up the excess RTV that squeezed out. Give RTV a little time to set up and your good to go. BTW, for those that are wondering, the water that is pushed into the RTV is what cures it. I've never had a rear main leak since using this method. It works on BB Buicks

 

[Agent86]

What are the Pipe Cleaners you referred to below? Is it a tube or something? Have a pic of it? Also, can this procedure be done with the Transmission on it? or does it have to be removed? I was also looking at the Kirbans Neopreme Rear Main Seal. Is that a good one to consider? If not, where can I get a good seal?

I have to disagree. I have rebuilt over a dozen TR motors. All have had stock cranks with neoprene rear main seals and never a leak. These motors have run anywhere from low 10's to high 12's and some have high miles on them, now with no problems or leaks. If it is a rebuild, I prefer to have the seal surface belt polished to eliminate irregularities and sharp edges. I have however, replaced the stock rope seal with the neoprene seal and had no problems. I do not use the side seals and pins. They will leak. Clean all surfaces really well and then squeeze RTV into the side slots until it squeezes out everywhere. Then take pipe cleaners soaked in water and shove one per side, ino the RTV in the side slots. Clip off the excess pipe cleaner and smooth up the excess RTV that squeezed out. Give RTV a little time to set up and your good to go. BTW, for those that are wondering, the water that is pushed into the RTV is what cures it. I've never had a rear main leak since using this method. It works on BB Buicks

 

[Lee Thompson]

This is all wrong

you can take this info for what it's worth . Last week I picked up my new short block from a very reputable builder in the Toronto Canada area . we got on the topic on rear main oil seals for Buick V6's . and he said alot of "you Buick V6 guys" are making a big mistake going with a neoprene type rear seals on the stock cranks . He's refering to stock cranks that have the "knurling" on the rear of the crank . He said the best seal for this type of application is the stock type rope seal that GM orig put in these engines . He uses neoprene rear main seals ONLY on other stock or aftermarket cranks that have the machine polished surface rather then being knurled .

Sorry, but just the opposite!!!!!

 

[SouthernCal GN]

How hard is it to replace? I have the new FelPro neoprene rubber one along with everything else to do the job. Also will be doing a timing chain at the time. Valvesprings will have to wait.

I have access to a lift and any tools I'll need.

So how hard is it to do in the car, without removing the trans?

Any help appreciated.

Scott

Put the car in the air; drop the oil and the oil pan. Leave the trans in place.

Follow these directions:
Rear Main Seal Replacement

Be careful to not nick the crank when removing the old seal- I prefer using a wooden dowel vice copper wire to push the old seal out.

Easy as pie!

 

[Lee Thompson]

Btw

All neophrene rear main seals for the V-6 Buick are made by the same company. No matter whose box or name is on it it is still the same seal.
You can not run a smooth seal on a smooth crank. One or both must have knurling on it. Had an eng. out 4 times one winter untill Doug Anderson @ Grooms eng. set me straight. That is how I know all the seals are the same. I bought a different seal each time and compared the # stamped in the molding. All the same #. So go to Autozone or the cheapest place and save your $. Best of luck.

 

[KWIKR 1]

Sorry, but just the opposite!!!!!

The obvious question is why would GM put a rope seal there instead of neophrene ? I'm just telling what was said to me by one of the most reputable shops in Toronto that has been building very high end engines for the last 35+ years . You can do with the info whatever you want .

http://www.turbobuick.com/forums/ge...188183-full-throttle-stroker-any-updates.html

 

[Lee Thompson]

Not trying to offend you, but

The obvious question is why would GM put a rope seal there instead of neophrene ? I'm just telling what was said to me by one of the most reputable shops in Toronto that has been building very high end engines for the last 35+ years . You can do with the info whatever you want .

http://www.turbobuick.com/forums/ge...188183-full-throttle-stroker-any-updates.html

I would assume they used the rope seal because it was cheaper. Everyone used to use a rope seal (I have had many 65-70 GTO all of which had rope seals)
Back to knurling--If you look @ a crank with knurling and study the pitch and direction you will see that is a pump to pump oil away from the seal to keep from flooding it. A few winter ago I went to a Stage II block and crank. The crank was a new BMS done by Moldex. It did not have knurling on it. The block was an earlier BMS block which took a Buick rear main seal. I had NEVER had a neophrene seal leak. After about 200-300 mile it developed a drip which steadly got worse. I had the eng. back out 2 times thinking I had done something wrong. Each time using a different brand seal. I rememberd an old article in the Club mag. about this Super Duper seal used by Grooms eng. Lassiter was selling this seal for around $10. I called to get one but they were out. So I talked to Doug Anderson to see if he would sell me one. BTW he was very nice and helpful. After many phone calls back and forth and looking @ the old seals we discovered that they all were the same seal (some reaserch showed they are made by a co. in Chicago). Also there is a co. in Texas called Enginetech where I can buy that seal for $3 but @ that price you have to buy 20 which is where the Club gets theirs because they were out when I call but had 20 on order. WWW. ENGINETECH.COM part # S1389
I had to have the crank knurled (a good friend of mine who is a Super machinest did it with a template from an old stock crank and did it by hand) I sent the crank back to Moldex (before my friend did his magic on it) and they said they could knurl it--got it back and there were some fine lines in it but very shallow and nothing compared to a stock crank. Whitey @ Moldex said it was nitritated and he ruined 3 tools putting the amount he go in. I installed it that way
and it did help but still leaked. That is when I was telling my friend about it so he took it with him and put the knurling in @ the correct angle and the correct tapered depth. Not one drop of oil has leaked since. Later Stage blocks take a BB Chevy seal which has knurling molded into the seal. The Buick seal does not have room for knurling since it is very narrow. Long story but my experince with rear seals. Best of luck.

 

[KWIKR 1]

I would assume they used the rope seal because it was cheaper. Everyone used to use a rope seal (I have had many 65-70 GTO all of which had rope seals)
Back to knurling--If you look @ a crank with knurling and study the pitch and direction you will see that is a pump to pump oil away from the seal to keep from flooding it. A few winter ago I went to a Stage II block and crank. The crank was a new BMS done by Moldex. It did not have knurling on it. The block was an earlier BMS block which took a Buick rear main seal. I had NEVER had a neophrene seal leak. After about 200-300 mile it developed a drip which steadly got worse. I had the eng. back out 2 times thinking I had done something wrong. Each time using a different brand seal. I rememberd an old article in the Club mag. about this Super Duper seal used by Grooms eng. Lassiter was selling this seal for around $10. I called to get one but they were out. So I talked to Doug Anderson to see if he would sell me one. BTW he was very nice and helpful. After many phone calls back and forth and looking @ the old seals we discovered that they all were the same seal (some reaserch showed they are made by a co. in Chicago). Also there is a co. in Texas called Enginetech where I can buy that seal for $3 but @ that price you have to buy 20 which is where the Club gets theirs because they were out when I call but had 20 on order. WWW. ENGINETECH.COM part # S1389
I had to have the crank knurled (a good friend of mine who is a Super machinest did it with a template from an old stock crank and did it by hand) I sent the crank back to Moldex (before my friend did his magic on it) and they said they could knurl it--got it back and there were some fine lines in it but very shallow and nothing compared to a stock crank. Whitey @ Moldex said it was nitritated and he ruined 3 tools putting the amount he go in. I installed it that way
and it did help but still leaked. That is when I was telling my friend about it so he took it with him and put the knurling in @ the correct angle and the correct tapered depth. Not one drop of oil has leaked since. Later Stage blocks take a BB Chevy seal which has knurling molded into the seal. The Buick seal does not have room for knurling since it is very narrow. Long story but my experince with rear seals. Best of luck.

no offence taken Lee. Just like to hear about engine builders take on related things to engine building and pass it along . and also to hear about experiences like yours .

 

[scojack_2001]

Thanks for all the help guys. I have almost everything to do the job. Got the timing chain and front covers seals. Just need to order a cam button and a few other things. This should be interesting, it will be the first time Ive ever taken the bottom end of a turbo motor apart...

I figure it will most likely leak, no matter what I do. Setting aside a few hours a couple nights during the week and all day Saturday. Should be done by the 23rd, I hope.

Anything else I should know about? Have access to lift & tools to do the job...

P.S. Thanks for the GNTType link... Should come in handy at the time.

 

[turbofabricator]

The trick to geting the RTV (silicone) to fill the entire side cavities, is to use a caulking gun. Most part stores carry Ultra-Black in a caulking gun cartridge. Just pump the silicone into the cavities and watch it ooze out all along the entire parting lines of the main cap. Cut the nozzle to fit into the cavity, and pump away. Real simple. (Thanks for the tip Geno)

 

[t-topflyer]

The fact that you have a lift will make it soooo much easier. I haven't had that luxury the few times I've done it. I think the hardest part of my install was getting the bolt and bracket that holds the transmission lines in place out and back in. Luckily my old rope seal came out in one piece. The new top portion of the neoprene seal was fairly easy to get in. Just lubed it and pushed it in with my thumb while making sure the outside lip on it didn't get stuck on the block and start pealing back. That happened to me the first time and I had to get a new seal. So make sure you curve it correctly when putting it in and avoid letting the lip catch the block. Turning the crank shaft while pushing it in may help. Definately use RTV vs the side seals that came with it. Otherwise, you won't be much better off than you were leakwise before doing the job.

 

[1986TR]

so what are pipe cleaners?:biggrin:

 

[turbodave231]

Pipe cleaners are fuzzy pieces of wire that pipe smokers use to clean out the mouthpiece of their pipe.

I 100% concurr with Lee's comments about knurling and neoprene seals. I too have a Moldex crank without the knurling. It is literally impossible to stop it from leaking........ and I've had very good luck with my "recipe" for stopping rear main leaks. Next time the crank is out, I'm looking into getting it knurled.

I do however like the rubber side seals and nails. But I first fill the main cap grooves 1/4 full of RTV before I push the side seal in place. This acts like a syringe and pushes the RTV into all the voids. The nails just add tension to the rubber and locks everthing in place.

 

[Lee Thompson]

I agree completely

Pipe cleaners are fuzzy pieces of wire that pipe smokers use to clean out the mouthpiece of their pipe.

I 100% concurr with Lee's comments about knurling and neoprene seals. I too have a Moldex crank without the knurling. It is literally impossible to stop it from leaking........ and I've had very good luck with my "recipe" for stopping rear main leaks. Next time the crank is out, I'm looking into getting it knurled.

I do however like the rubber side seals and nails. But I first fill the main cap grooves 1/4 full of RTV before I push the side seal in place. This acts like a syringe and pushes the RTV into all the voids. The nails just add tension to the rubber and locks everthing in place.

That is the way I have always installed rear seals--I also use a PAPER thin coat of Loctite 518 on the mating surface of the cap. IMO, if done this way it WILL NOT leak. Make sure all parts are CLEAN.

 

[scojack_2001]

Ive got everything I need, I think. Got my oil and filter yesterday($40 ) and my parts came in. They include:

FelPro neoprene rear main seal
FelPro front crankshaft seal
Edelbrock double roller timing chain (hopefully it will last a while)
GM needle bearing cam button
GM gaskets for the front
Duttwieler thick cork oil pan gasket
GM oil pickup and gasket
5qts. Mobil-1 10w30 & PF52 filter
braided oil feed line for wasted stock turbo (hopefully it will last a bit longer)

I still need to get the Ultra Black cartridge for the caulk gun. My question is how long do I have to let it set up? When I did the valve covers on my old 307 car, I let it sit for 24hrs. Do I have to do the same here? I can probably let it set up while I put the front back together, and put the pan on the next day. I already had to drop a pan, its really not too hard (takes some "convincing").

The only thing Im worried about is it leaking afterward. If installed properly, how long should it last? I know it will leak from somewhere, just because its a Buick.

Hopefully this will all get done next weekend with no problem so I can go to Cecil County for the March 1st T&T.

Any other tips/advice appreciated.

Scott

 

[84BuickGNYorkPA]

Scott,

You should be ready to go, I would use different oil though, if your not adding some type of supplement. I use the Shell Rotella T and 1/2 container of GM EOS. This is assuming that you have a flat tappet cam, if you have a roller cam, ignore what I just said.

Chuck

 

[scojack_2001]

Scott,

You should be ready to go, I would use different oil though, if your not adding some type of supplement. I use the Shell Rotella T and 1/2 container of GM EOS. This is assuming that you have a flat tappet cam, if you have a roller cam, ignore what I just said.

Chuck

Chuck, the previous owner ran the Mobil-1 in the car, so Im reluctant to change. Ive heard that you can switch from synthetic back to conventional due to the different properties. My car runs fine with it, so I really see no reason to change. I believe my car has the original cam in it, along with everything else. I'll find out next weekend when I take it apart.