Hello,
I'm new posting here but have enjoyed this site for years. I figured for sure someone here would know the answer to my question.

OK, dumb question,
Getting ready to install new clutch in my 86 GT 2.8 getrag 5spd, and want to replace the 2.8's rear main seal at the same time. Is this easy to do? Can someone list the details on how to do this after the trans and flywheel are off the motor. Pic's would be a great help also.

any help is greatly appreciated!

There are 3 types of rear mains I know of. One is a split 50/50 2 piece one, another is the single disk type that slips over the crank. Older one (dont know if any Fieros had) is pretty much a tarred piece of rope put in a groove in the main cap/block. It would be a good idea since you do have to have the trans out to replace the single disk one.

Well I can find three different types of seals that it could be. Two from Alldata (which uses factor service manuals) and one from Haynes. The two from Alldata are a single piece seal the requires removal of the crankshaft and the other that is a single piece seal but can be removed without having to remove the crankshaft. The latter of the two is very similar to a wheel bearing seal and they are quite easy to change (pry it out and tap in the new one). The other is self explanatory I.E. remove the crank. Haynes shows a two piece lip seal that’s not too hard to replace but does require the removal of the end bearing cap. Defiantly something you want to do if possible as there’s nothing worse than having to replace the clutch a second time because it got coated with oil.

You will likely have the single piece unit that presses in. It is ment to be installed using a tool to press it in place, but I think you could probably install it by carefully hammering it in. There are different types of this seal also, the later ones made for automatics are a rubber seal only, some have the rubber seal and an outter felt seal to keep the clutch dust out of the seal area, I will see if I can find the GM part number for this one, but I am sure either would do fine for the time you will be needing it to work. Larry

This is a modern, metric engine so you won't find any rope seals for it. There may be some 2 piece seals out there, but by far the best and likely only thing you'll find is the one piece seal. To get the old seal out without removing the oil pan and rear crank bearing cap, you'll have to puncture the side of the old seal and try to pry it out without scoring the crankshaft journal. If you're not successful then you'll have to remove the oil pan and the rear bearing cap. Here are a couple pictures of a typical one piece seal on a 2.8L engine:





It normally gets slipped onto the crankshaft before the rear bearing cap is installed but it may be possible to install it without removing the cap. The same type of seal is used on almost every engine out there now. I installed my Northstar engine rear crank seal by making a simple tool that pushes the seal into place evenly and squarely rather than trying to hammer it in and possibly ruin it. I just used an old piece of PVC pipe and a metal plate that I drilled to mate with a couple of the flywheel holes and drew it into place with some bolts:

Just took a peek at the Rock Auto site. Looks like two 1 piece seals were used- 1st design & 2nd design- in 86. The outer diameter differs by about 0.1" (2.5mm). The 1st design is 3.5x" and the 2nd 3.6x". This is from a website so should be verified but a quick diameter measurement of the existing seal will ultimately tell the tale I imagine.

BR's,

Mark

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86 SE V6 4 speed
86 SE V6 Auto
2008 G6 GT "Street" Coupe
2005 Buick 3.6 Rendezvous
2001 Olds Silhouette (AKA The Band Van)

WOW,
Thanks to everyone who posted for the great info! A speacial thanks to Bloozberry for the fantastic photos!

I look forward to spending a lot of time at this site. I have some tips and tricks I want to post that might help other users. Gonna start getting photos and info put together just as soon as I get my GT back on the road.

Have a great weekend everybody!

Thanks for the pics bloozberry!! Looks like 3" PVC will do. The plastic and more sturdy portion of the seals faces inward, hopefully I don't muck it up.