Rear Main Seal Replacement Instructions:

Discussion in 'Small Block Tech' started by sean Buick 76, Nov 21, 2006.

  1. Jclstrike

    Jclstrike Well-Known Member

    Looks like I will have to try to replace mine as well. Buying a seal from TA and plan on doing it with the engine in the car. With mine being a 4 speed anything else I need to know. Probally doing it in November when I store the car.
     
  2. Jclstrike

    Jclstrike Well-Known Member

    Anybody have thoughts on my above question? Also with the TA seal is it required to drop crank. Heard for rope that a tool existed so you would not have too but not sure it worked well. thanks
     
  3. Johns40

    Johns40 Active Member

    No Jclstrike, you don't have to drop the crank. I have a Regal subframe in the coupe and had to raise the motor an inch or so to get the pan out. I loosened the rear mount and used the balancer to raise the motor with a bottle jack.

    The biggest problem was getting the rubber blocks and pins back in. One of them was slightly too large and would not go into the slot. I had to hand sand it down to size (a very tedious job that just took a mic and a little time).

    I used the installation instructions in the first thread in this post. It was an easy go with those directions.

    Here is the link:

    http://www.v8buick.com/attachment.php?attachmentid=108744&d=1202987299

    Good Luck
     
  4. cb3071

    cb3071 Well-Known Member

    I know a bunch of you guys will tell me I'm nuts for doing it-but my car had sat for years before I restored it. The rear seal leaked for the first 6 months. Was going to replace it but decided to try the STP oil leak treatment. Put it in and it took about 2 weeks, stopped leaking, changed the oil after 2000 miles and has never leaked since. Runs great. 112K and doesn't burn any oil...no problems yet and it's been over a year. Maybe worth a shot if someone has a seal that may be "dried out".

    71 Skylark 350
     
  5. eagleguy

    eagleguy 1971 Skylark Custom

    Got 2 years out of the TA seal set up and she leaked again. This time around I tried the Ford part number and so far so good.
     
  6. sean Buick 76

    sean Buick 76 Buick Nut

    Bump to the top... Remember guys the TA part is the same as the Ford 460 seal. :TU:
     
  7. m/w

    m/w Al Baker (Z 55 )

    I do believe the rear seal tool is called a sneaky pete , it's just a little wire & hook that goes around the crank & pulls the new seal in. I haven't tried it cause i bought the camaro & 455 & poor baby brother is still in a corner of the garage . This moyor was rebuilt about 2 yrs before i pulled it and the rear main seal leaked from the get go . The mech did a great job on the over haul but screwed up on the rear seal ,tried to get warranty no dice .So that was when we tooled up hardcore and did all our on stuff . Sorry to wander off topic . Take care & work safe Later Bake
     
  8. 71skylarkfriend

    71skylarkfriend Well-Known Member

    with so many guys doing this, Well lets say I to am going to grow some and try it. I really hope I am so excited afterwards that I cant sleep, Wife might not be so happy LOL.

    I will let you know how I do. I find it really Amazing that a ford part and a Buick part are exactly the same, VERY INTERESTING.

    Thanks
    Chris
     
  9. sean Buick 76

    sean Buick 76 Buick Nut

    Buick never made the rear main seal for the 350. Ford made a seal for the 460 that fits the Buick 350 by chance. Not sure who found this out though maybe TA?
     
  10. tinker14bs

    tinker14bs Well-Known Member

    Wish I would have found this thread one week earlier. Thought I was having an oil pan gasket leak and replaced the oil pan gasket. Still leaks...The frustrating thing was I had the TA neoprene seal sitting in a tool box drawer I had forgotten about. I was assuming I needed to pull the crank to replace the rear main. It looks like I will be laying back on the creeper this weekend. I was looking at the TA seal kit and the orange side seals for the cap have a hole where it looks like a metal pin would run, but there isn't a metal pin in the kit. Is there no metal pins required, or do I lose them somehow?
     
  11. sean Buick 76

    sean Buick 76 Buick Nut

    It has been a while but I am pretty sure my TA rear main kit came with the 2 halfs of the Ford 460 seal, two blocks for sealing the caps sides, and two pins for expanding the blocks once they are in...

    If all you are missing is the two pins then drive in a small nail on each side and then grind off the head flush. If you are missing the blocks then buy a regular 350 rear main seal from any parts store and it will have the blocks in there.
     
  12. sean Buick 76

    sean Buick 76 Buick Nut

    A few weeks back when I was installing a rear main in a fresh 350 I did something different than I have before and I think it is a really good idea to ensure no leak between the sides of the cap and the block. Before I put the rear cap in place I have always put a thin skim of "the right stuff" sealant onto the sides of the cap where they meet the block, but this time I also injected the sealant into the little slots where the rubber chunks slide in. I injected the sealant using my sealant gun into the little slot till it squeezed out of both the front and back of the cap. I removed the excess with a knife right away and then installed the little rubber chunks, the pins, and then cleaned up the little extra bit of sealant that came out of the ends as the rubber was slid into place. I am sure that many people end up having leaks between the cap and block on the sides and this should eliminate the issue.

    To clarify I injected the sealant into the slot where the rubber blocks fit AFTER I had installed the rear main cap. So the cap is in place and mains torqued and then I cleaned up any extra sealant that pushed out from between the cap and the block, added the rubber chunks, tapped in the pins, and then cleaned up any little bit of sealant that squeezed out.

    I understand that extra sealant can plug up oiling systems however when used carefully and excess removed it is a safe method.
     
    Last edited: Nov 13, 2013
  13. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    Got any pics of that?

    If not the next time you do it please take some,and post them. Thanks

    Derek
     
  14. sean Buick 76

    sean Buick 76 Buick Nut

    I do not have any pics, should have taken some... I am disassembling my favorite 73 engine in a few weeks and when I put it back together I will document the rear main install with pics... Doing a low buck rebuild on the engine for my book, as the engine only has 35,000 miles and ran great when I pulled it to scrap the car due to rust. I could not believe it when I reviewed the oil change receipts and maintenance receipts and found it to be a documented 35,000 mile car! Too bad the vinyl roof trapped in moisture and the roof rusted out.

    Going to install a Northern Autoparts master rebuild kit without any machine work unless I find some bad bearings or cylinder walls. Ran fine when I pulled it:

    http://www.youtube.com/watch?v=GljRr5PauLI

    I will be saving this engine as a spare for my 75 Regal which is getting a single turbocharger.


    This pic might help:

    [​IMG]
     
  15. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    Thats cool Sean,thanks.


    Derek
     
  16. Gary Farmer

    Gary Farmer "The Paradigm Shifter"

    My 4300 lb. '68 LeSabre did that on wet pavement with the ST300. Had to be careful when the roads were wet! :)

    Nail it from a standstill on wet pavement facing a straight stretch of road and it would rev up to almost shifting point (about 78 mph speedometer reading) and stay that way until it reached about 60-65 MPH actual speed. lol

    The ST300 2 speed tranny shifted at 80 typically from low to high, and would spin on wet pavement from 20-30 mph rolling start. This was with the 350. You can imagine what the '70 455 did in it. I couldn't even drive it on wet pavement.

    God I miss that car. That 350 was a beast for what it was.

    Too bad your '73 had to be scrapped. Was it just the roof that was rusted out? If it didn't rot out the pillars or floor pans too bad it might be worth saving having only 35,000 actual miles.

    Good to see you're freshening it up. Gonna use the stock cam and bump dynamic compression or ?

    ---------- Post added at 01:17 AM ---------- Previous post was at 01:13 AM ----------

    http://www.youtube.com/watch?v=VGYg5GuLqXY

    Oh man, I missed my calling! I used to do this **** for free, I didn't know you could get paid for it! haha
     
  17. sean Buick 76

    sean Buick 76 Buick Nut

    My plan is to just mill the heads if I have to in order to get it to 8.5:1 and then use a custom ground cam for the turbo application. I will not even bother ordering the camshaft unless the original engine in the 75 takes dump under boost... Otherwise this 73 engine will just sit fresh on the stand beside the other fresh spares for my 70.

    The car could have been saved by someone with enough motivation, I just bought it for a spare engine and trans and for a weekend of fun. The car was of little value being a 4 door, no one would spend the time and money to fix it I don't think. The interior got mouldy due to the roof rotting out and I had no interest in messing around with a mouldy car... Especially since I had the 76 at the time which was in much better shape and my 75 Regal which I still have:


    [​IMG]
     
  18. 72newbiebuick

    72newbiebuick Gold Level Contributor

    OK guys I know this a long and old thread but - looks like the rope seal on my 350 is seeping now. The BS40032 number was a good number from Napa. Is this still a good seal to use, and by what I read this seal CAN be replaced without pulling the engine, yes?

    Mark
     
  19. magilla2

    magilla2 Well-Known Member

    Old thread, but good stuff.

    replaced the rear main with a Ford 460 Viton seal, and used the rubber end block and pins from a Buick 231 rear main seal kit that I had on the shelf.

    I used Permatex Ultra Black maximum oil resistance RTV under and along the sides of the bearing retainer and in the side holes. Coated both sides of the rubber blocks with it, tapped them down, then inserted the pins. RTV sqooooshed out (just a small bead) along the entire perimeter on both sides. Torqued the cap bolts to spec, cut off 1/8" of the rubber side blocks that protruded until it was flush.

    Then I used Permatex "The Right Stuff" on the oil pan surface. Man, is that stuff AWESOME!!!! No cork gasket.

    By the time I got my 16 bolts screwed in, it was ready. Torqued to 36 inch-lbs (snug), got a good bead along the entire surface that sqooooshed out, and waited 10 minutes. Torqued to 8 ft-lbs, and just a little more came out. Waited another 20 minutes, and then torqued to 14 ft-lbs. It didn't change at all. I am positive that I have a good seal all the way around.

    Note, I thoroughly cleaned both sides of the mating surface with solvent and wiped down with rubbing alcohol. I used a 1/4" bead, and went inside of the bolt holes and circled them. The motor was inverted on a stand, and I set the oil pan on top of the bead, then snugged down until the right stuff just oozed out.

    Anyway, just wanted to throw a hearty "thank you" out there to Sean! I would have used a rope seal had I not read this and other threads about the 460 seal.

    PS: Sean, the 350 flywheel you sent me got resurfaced, and fits perfectly on the motor!

    Cheers!
     
  20. jay3000

    jay3000 RIP 1-16-21

    Should someone see this and wonder. The answer is, absolutely.
     

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