Re: Spider leaking differential (long)

[wcm3@domain.elided (William C. Macfarland)]

I looked into replacing the leaking oil seal on my '77 Spider, and it 
doesn't look easy. The shop manual provides information on '78+ spider
transmissions:

Disassembly
1. Remove drive shaft. Remove gear oil. Remove differential. Remove rear cover and both 
axle shafts (length of sentence is not proportional to amount of work).
2. Remove axle bearing caps, adjuster rings, and roller bearing cups. 
Withdraw gears and bearings.
3. Using a special tool that holds the drive shaft U-joint sleeve in place, 
loosen pinion nut.
4. Remove pinion, and oil seal, oil slinger wahser, front roller bearing, 
collapsable spacer, rear roller bearing, and thrust washer. Remove gasket
5. Drink a beer, be happy your alive.

Assembly
1. Wave a magic wand over the axles (Fiat Part numberJ28099). It's probably 
a good time to replace some roller bearings and stuff.
2. Determine the thickness of bevel pinion rear bearing thrust washer 
(involves a dial indicator, a pencil, paper, and a beer).
3. Order new bevel pionion rear bearing thrust washer from Fiat Plus. Wait
a week for it to arrive from California.
4. Install new rear thrust washer, roller bearing, and collapsable spacer
(it may be possible to use coll. spacer again).
5. Place pinion gear into housing. Install front roller bearing, oil slinger,
oil seal and U-joint sleave.
6. Invite a friend over, tell him/her you have free beer. Use friend to help
you torque pinion bolt to "between 87 and 166 ft.lb."  The turning torque
of the bevel pinion should be monitored using a dynanometer such that the 
bearing preload is not set too high.
7. Re-install axles (use magic wand again), back cover. Re-install 
differential. Add gear oil. Install drive shaft.
8. Drink a beer. Life is good.

Now an alternative procedure is the following:

1. Put newspaper under differential while parking.
2. Add gear oil every now and then (thanks JS for the suggestion)
3. Drink a beer. Life is good.

As you can see, the method described in the shop manual involves meeting more
people, buying more tools, spending more time with your Fiat, and drinking
more beer. Isn't that what owning a Fiat is all about?


Side note: Does anyone have the left and right front shock tower sheet metal
available?

Thanks,
Bill in NC
'77 Spider (drip. . . drip  . . .)