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In over my head...

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rdegrie77MGB

rdegrie77MGB

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I'm about to dive in over my head into a repair I've never done before... the dreaded rear main oil seal on my 77 MGB. I need some tips from anyone who has replaced the rear main on their own. I'd appreciate any advice you can give that you learned from your experience. Thanks!
 
The only advise to be had is: Pull the engine/gearbox and do it ONE time right. That may not be the answer ya want, but it truly IS the only way... just remember the "slippery slope" theorum: Once you're to that point, there's a whole lot of OTHER things you could do to it to make life easier "down th' road." IE: Why not renew the clutch/pp/t-o bearing, front seal, freeze plugs... the list goes on...

Good luck.
 
I'd be willing to beta couple of 6 packs that you will find that the rubber tranny mounts have turned into goo. The oil leaks ( more commonly referred to as the automatic underbody anti-rust system) on your B has this effect on the rubber. Buy them before you pull the engine. I KNOW you are going to need them!
Also make sure to get new locking plates for the rear as I also know that unbending and rebending the tabs will cause a bunch to break off.
If the rear seal has been pumping loads of oil, you may also need a new clutch disc if it is saturated and if I put on a disc, I put on a new cover as I don't want to be doing this again in 10,000 miles.
I wouldn't worry about freeze plugs.
If your timing cover is weeping it is also a very good time to renew that seal as well. You won't know if the pulley needs a speedi-sleeve until you pull it otherwise it is cheap insurance to put in a new seal and a new gasket on the cover. One hint there is to keep track of where each bolt comes from as there are different sizes and lengths.
Tape some cardbord onto the shelf just below the heater to keep the motor/tranny from beating the bejesus out of the lip and heat shield there when reinstalling it.
Make sure the motor mounts aren't about clapped out too.
As the doctor above said, slippery slope!
 
heh... look at it as a "bonding experience"! One must have "simpatico with the equipment." The more intimate you are with the gear, the less likely it is to leave you scratching your head while standing beside it along some highway at night. Learning the systems means ~disassemble!~ The Robert Bentley workshop manual is an invaluable tool.

Tom and I both forgot to mention the input and output seals onna transmixer, too. Good insurance. They're every bit as hard to replace (well, admittedly the rear one CAN be done lying on yer back, upside down inna DIRT... I guarantee /ubbthreads/images/graemlins/wink.gif) after the unit is back in situ. That $10 input shaft seal is a worthy candidate for consideration though. I've gone thru two sets of mushy tranny mounts rather than pull it all down in the past. Got sooo familiar with pullin' the unit from my first car I could have it out, sittin' in front of the car inside an hour. <smirk mode> Them was the days. </smirk mode> Now, when it comes down, I go to extreme measures to insure it won't be necessary to yank it again for a LOOONG time.

Welcome to the wild and wonderful world of MG ownership. Not at all for the faint of heart: You're a brave lad. ;}
 
Yeah... let's see if you say that after spending a months' worth of Saturday evenings on it /ubbthreads/images/graemlins/wink.gif
 
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