'80-up 727 leaky shift and throttle shaft seal(s) replacement.

[babywag]

Never seen anyone take pics of process so I will since I finally decided to replace them, after years of neglecting the leaky pig.

Kind of a PITA, but there are worse jobs on a FSJ.

Different ways to do this, I believe this to be easier than crawling around on you back under a FSJ.

BE SAFE YOU WILL BE REMOVING THE SHIFT SHAFT, apply the parking brake, and chock the wheels!
In case you accidentally bump it out of gear.

Remove the passenger seat, and roll/fold the carpet out of your way.
Then you'll need to remove the access cover, and you have room to work from above!



You will likely see a nasty buildup around the seal(s) like this.



You'll need to clean this all up, use whatever you prefer. I like purple power and brake clean. You want it pretty much spotless, so nuke it and let it sit for a while.

While it is soaking you can remove the throttle and shifter shaft levers. Just loosen the pinch bolts and spread them a little, they pull right off. Set them off to the the side.

Then you'll be left with this...



Time for more cleaning!

Cleaned up and ready for the not so fun part.



You'll want to remove the rear tranny line for more room to work, and push it off to the side gently.



Get a little awl and dig in and pry the seal out, it WILL fight you a lot.
They make a tool for this, but I don't have one. It screws into the seal, probably like $15 @ NAPA?






Seal removed...they don't want to come out, and need to do a little more cleaning.
Be sure to clean the shaft w/ some fine sandpaper, or steel wool.
Needs to be clean or it might leak again.

New seal installed. just tap it in w/ a long socket.



Now remove the e-clip, and washer for the throttle shaft. Have a magnet standing by to catch them. You don't want to lose this little guy!



And remove the washer



Use a little screwdriver, or awl to pull out the little rubber seal.



Clean the bore & shaft w/ fine sandpaper or steel wool. Blow out the crud w/ brake clean or compressed air.
It's normal for the shaft to seem loose.
Pull up on the shaft and push the new little seal back in w/ your fingers.
Be sure to pay attention to which way it came out/goes back in.
Once you get it pushed in, reinstall the washer, pull up on the shaft and slide the e-clip back on. USE THE MAGNET again, you do NOT want to lose that e-clip.



Done with seals, now put everything else back together.
Hopefully your transmission will no longer leak from here?

Might also be a good time to take a look @ the reverse/neutral safety switch? They can leak too.

[serehill]

yeah

I did this 2 times & after a very short time it leaked again. I talked to a mechanic friend of mine & he asked if I made sure the shaft wasn't corroded.
I never had it out. So on the third time I pulled the pan & transmission valve bodyto look at the shaft. Since it sits pointing up it had sediment & rust pit the surface of the shaft. I emery clothed the shaft. Then I clear coated the shaft it hasn't leaked since. s If this doesn't work or you find a bunch of trash around the shaft. Look closely at the surface of the shaft.

[Strode]

Nice write up Tony, thanks.

[babywag]

I did this 2 times & after a very short time it leaked again. I talked to a mechanic friend of mine & he asked if I made sure the shaft wasn't corroded.
I never had it out. So on the third time I pulled the pan & transmission valve bodyto look at the shaft. Since it sits pointing up it had sediment & rust pit the surface of the shaft. I emery clothed the shaft. Then I clear coated the shaft it hasn't leaked since. s If this doesn't work or you find a bunch of trash around the shaft. Look closely at the surface of the shaft.

Well you can see in pics my shaft looked pretty clean.
I sudo polished it wilth 800 grit sandpaper and 000steel wool as well. That is most important step.
They need to be cleaned properly or yeah it will leak.
Mine has been leaking for years, if it still leaks good excuse to drop valve body and do a shift kit?

[serehill]

Yeah

I missed a complete clean because I did not recognize that the shaft had dropped down some after loosening the nut. I didn't clean it thoroughly so I missed the dropped part anyway. It just ground the new seal up. Shift kit why not. It also gives you a good chance to clean the valve body & inspect the tranny. I was surprised how easy the valve body was to pull.

[babywag]

Cleaned up the cruddy shift & throttle levers...

Before...can barely even see the shift lever, YUK!


After...


Replaced the dipstick o-ring, And installed a drain plug in the pan today. Chose this spot because it'll clear the crossmember when draining.
The first hole I made was too close to the filter, and also fluid would have hit the crossmember when draining.
Could have made it work, but decided to weld it up, and move/make a new hole.
Also replaced the filter, beat the pan straight, and it got a reusable gasket.



I use an old castle nut from ball joints, the slots allow the fluid to drain.
Never loosen up like the crappy aftermarket ones.


It'll get some drive time before fluid will be changed again. Stuff was nasty 11 years & ~20K since I changed it last.
Ran it for ~30 minutes, and drove it around the block a few times. Bone dry, not a leak in sight...YET!

Update:
Over a year now and still leak free, Yay!

[67GMC]

Did cleaning up the shift and throttle levers get rid of any slop in the shifter? My shifter is really sloppy. Does changing the rubber bushings make a difference? Great write up.

[babywag]

No slop fix here, if you're shifter has slop you'll likely need to replace the plastic bushings mounted to the frame.
There is also a small rubber bushing in the shift arm, you can see it in the pic.
If that is worn badly it may lead to slop?

[67GMC]

No slop fix here, if you're shifter has slop you'll likely need to replace the plastic bushings mounted to the frame.
There is also a small rubber bushing in the shift arm, you can see it in the pic.
If that is worn badly it may lead to slop?

Thanks. I always have a struggle with linkages and getting them back together and working once disassembled.