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Changing front oil seal on transmission.

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I just changed the front oil seal on my transmission. Pretty straight forward operation. I seated the new seal down to the bottom of the race using the old seal body as a driving plate in a vice. Squeezed in tightly, not a problem, no distortion. Put a fresh gasket on with some Hylomar and tightened up. My concern is the shaft on the transmission turns all too freely. Shouldn't there be a bit of a bind on it with a fresh seal. The spring is definitely on the seal lips. Lubed it up a bit.
I mean, it doesn't spin loosely, but it does turn easily (the splined shaft). It this normal?
 
Yep it's normal.

To tight you get excess wear...
I did an overhaul on my spare transmission nine months ago. filled it with gear oil and stored in upright on the bell housing. No leaks from the front, and everything still turns easily.

Ray
 
Tip it forward like OT above. If nothing runs out, you win. If fluid drains out, back to drawing board.
 
Hey Bill,

You are a week or so ahead of me. Maybe months
if Crytpy keeps acting out.

I was going to use the aviation gasket sealant
you had me purchase for the valve cover gasket.

What is Hylomar? and should I purchase it?

How many hours did it take you to change out
the oil seal? I have not quite figured out how
to remove the existing.

Actually my new TR6 seal looks different that the
existin one. But that's Crypty!

regards,

d
 
Hi Dale. You can remove the seal with a "seal remover" bar that NAPA sells. Looks like a weird, thin hatchet. It will get right under the seal and pop it out. 10 seconds. Otherwise, you will be digging for hours and may score the metal surrounding the seal. Not worth it. 8 bucks is cheap insurance. Aviation works great. I would have used it on mine but the darn bottle has developed legs or is hiding from me. I had an old tube of Hylomar (blue, jelly-like sealant) that was originally used on my gasket (you can tell, it is the only one that looks like that) so I used it. Really hard to find Hylomar anymore for some reason. I wouldn't hesitate to use the Aviation.

Total change time = 15 minutes.

Oil up the new seal with motor oil, and very evenly press it in. A plastic mallet can be use to carefully tap around the perimeter of the new seal to drive it home. It needs to seat all the way to the bottom of the well. You won't be able to get it completely in with the mallet. I used the old seal (which is rigid plastic around the edge), lined it up perfectly with the new, half seated seal, and used a vice to carefully set it. The old seal acted as a seating ring.
A large socket would work but the chance of finding the perfect fit is nil. Just be careful and take your time. It will drive home.
 
I'm trying to recall if someone had posted a picture of the operation to replace that seal?

I'd like to know what was involved, mechanically.
 
Remove transmission.


Take out the crossbar and fork. Unbolt the flange (4 bolts) and pull off. The gasket usually is stuck to the flange. The flange has the oil seal embedded inside it. This is where you really need an oil seal removal tool. Hooks underneath the seal and pops it out. The insertion of the seal is as above in my post before this on. The 4 bolts use only copper washers. A little sealant on them won't hurt.

Voila..
 
Hey Bill,

Since you are ahead of me, one more
question or two about the flange.

I purchased 4 new SAE 8 bolts but they
are maybe a 1/16" longer than the ones
I removed. Should I grind them down? or
install additional steel washers?

The DPO had no washers. I purchased the 4 copper
washers. Do they go between the bolt heads and
flange plate on the outside? Or the flange plate
inside as a kinda oil seal?
 
Whoa Dale! Those are not SAE (fine thread) bolts. They are standard coarse thread. Why. It's aluminum, you shouldn't use fine thread in aluminum. The originals were coarse thread, with the copper washers on the outside, under the bolt head. Don't put a whole bunch of torque on these bolts, will strip the aluminum.
 
Hey Bill,

We do not have NAPA here on the island.
Could you post a photo of the oil seal
removal tool.... with a ruler next to it.

Maybe I can fabricate the tool with my
bench grinder and thin steel sheet stock?

thanks,

d?
 
i just bought that exact tool at AutoZone this past weekend for about $9.
 
Interestingly, I bought my new oil seal from Moss and installed it. It fit very tightly, had to drive it in using the old removed seal as a drift. Today, I got in from TRF their version of the same seal. The one from TRF is made in UK and the whole outer shell is made of metal! Looks like the quality is better from TRF. I would take the Moss seal out and install the new TRF one but because I had to drive it in so hard, I am sure that it is sealed. The inner lip look the same on both.
Man, I hate that. When one item obviously is a cheap-looking knockoff from across the Pacific and the other is the real deal. Makes you wonder.
 
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