Crankshaft rear oil seal

Engine, Transmission and related drivetrain.
Three B's Racing
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Re: Crankshaft rear oil seal

Postby Three B's Racing » 04 Oct 2016 06:50

The bushing is a light press fit and will go in with a socket as Byron said. I use the socket method all the time with no issues but don't put any lube on the bushing put it in dry it's self lubricating and lube may cause issues with the trans input shaft. Freezing it as greenthumb mentioned will simply make it easier to install with socket, a one beer job Meng!
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SteveEdmonton
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Re: Crankshaft rear oil seal

Postby SteveEdmonton » 05 Oct 2016 16:16

Bushing project hasn't been started yet, but based on advice received I think I'll try using a socket as the "pusher" and freeze the bushing beforehand-- even though I'm a bit concerned about the cold temp making it more brittle and thus perhaps even more likely to fracture. (Am I over-thinking this, or what?)

The wrinkles in the project just keep coming though. After Ken installed the new rear seal (crank seal) the other day, I got a call a few hours later saying he realized he hadn't thought enough while doing it. Working mostly on British stuff, he wasn't prepared for the excessive room "behind" the seal and therefore had just kept tapping away, figuring it would bottom at about the right place. But it just kept going... and in hindsight he realized this was a problem. Here's a pic of the situation:
IMG_8378 comp.jpg
IMG_8378 comp.jpg (183.01 KiB) Viewed 174 times

The seal is recessed about 6-7 mm-- it isn't quite "square" on the crank. Presumably it could be squared up with a little more tapping. However, both Ken and I assume it needs to be replaced with another new seal, if only because it's much too deeply recessed. The worry is that it'll leak-- we don't know why, but it just seems possible-- if it's this far out of place.

Anybody got experience with this issue? I'm assuming it wouldn't be super hard to R & R this seal again, now that I know how to do it. :) My only worry is how to get a screwdriver "into" the seal when it's been driven this far in. The leverage and angle of attack are far from ideal.

OTOH, if the seal seems likely to work just fine as it is, I don't want to fix a non-existent problem.

Oh, and yes the paint will come off the crank before I got any farther. And if this seal does need to come out, I'll certainly use scotchbrite and 2000 grit to clean the crank boss too before re-assembly.
'71 4-door
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okayfine
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Re: Crankshaft rear oil seal

Postby okayfine » 05 Oct 2016 21:26

If the seal's not square, it won't work. You won't be able to reuse that seal if you want to reposition it. You'll need a new one. I've always installed them flush to the block surface.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson

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SteveEdmonton
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Re: Crankshaft rear oil seal

Postby SteveEdmonton » 09 Oct 2016 13:35

It's Thanksgiving Day here in Canada.... and among other things, I'm thankful to have finally gotten this crank seal installed.

Can't believe how easy it was, once I knew how to do it. A lot of things in life are like that I guess... The badly installed seal came out with no issues and then it was time to clean & polish the crank boss. No more paint or scum.
IMG_8380 comp.jpg
IMG_8380 comp.jpg (129.06 KiB) Viewed 142 times

The new seal went in with a few rounds of tapping. I didn't see specs on this anywhere but it's "square" within 0.1 mm (.004") all the way around so I'm hoping it'll seal well-- and for a long time.
IMG_8381 seal in comp.jpg
IMG_8381 seal in comp.jpg (159.98 KiB) Viewed 142 times

While everything was apart I also shortened the crank bolts by about 1.8 mm each. I hadn't heard any noise at all but the springs on the clutch disk had just barely started to contact the crank bolts. Negligible damage to the springs, but this was definitely the time to prevent the issue getting worse as the clutch disk wears and moves those springs closer to the flywheel. I measured down to its rivets, did the math, and decided that if the crank-bolt heads are less than 8.0mm in height, I won't have this issue again. Now it's done.
IMG_8383 crank-bolt ground comp.jpg
IMG_8383 crank-bolt ground comp.jpg (150.28 KiB) Viewed 142 times

I don't think I've ever assembled the flywheel & clutch while the engine was out, but figured I'd try it. Much easier than wrestling with them with the engine in situ. It was super nice to have everything ready for the tranny before the engine even went back in.
IMG_8388 clutch on comp.jpg
IMG_8388 clutch on comp.jpg (161.84 KiB) Viewed 142 times

Thanks, too, to those who offered advice and encouragement along the way! I'm considering this thread a "wrap"! :o
IMG_8399 comp.jpg
IMG_8399 comp.jpg (196.5 KiB) Viewed 142 times
'71 4-door
'74 MGB-GT
'04 Miata

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bertvorgon
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Re: Crankshaft rear oil seal

Postby bertvorgon » 09 Oct 2016 13:38

I had an issue with the crank bolts hitting my springs, did not even hear it, till a spring came loose. Andy turned the bolt heads down for me.
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