[DeTomaso] Today... in Asa Jay's Garage

[John Taphorn]

Asa

While you have the ZF out, check the slop in the clutch withdrawal shaft 
(1001).  The shaft rides on two sets of needle bearings (1003).  Previouse 
ZF washings could have introduced water to these bearings and they may be 
compromised.

When these bearings are bad, the initial action of the slave cylinder on the 
bellcrank is to push the clutch withdrawal shaft back rather than rotate it 
to actuate the throwout bearing loosing precious clearance.

You can tell if they are bad by pushing the shaft back and forth to see how 
much it rocks in the bearing.  Most used ZFs that I have seen out of the car 
suffer this malady. There is usually collateral damage on the clutch 
withdrawal shaft from the bearings. Should you believe that your needle 
bearings are still good, try to get some lubrication on them.  Chances are 
that when you hosed down the interior of the bellhosing, you got them good 
and wet.  There are no seals protecting them from the inside.

When rebuilding ZFs, I now use three seals, one on the exterior and two on 
the interior to protect the needle bearings.  The forth isn't necessary as 
it is protected by the cover. The bearings and seals are cheap.

Second, extracting the differential is no small task.  A special puller is 
necesary to pull the side conical bearings first and this tool will not be 
found anywhere but in the ZF tool kit.  The alternative approach is to 
remove the 5mm allen head bolts that hold the differential together.  With 
these bolts removed the diff can be separated and taken out with the side 
bearings in place.  The problem here is the allen bolts have shallow 
orifaces for the 5mm allen bit and they round very easily as the are 
generally very tight.  Then, you are left drilling them out.  I am 
embarrassed to admit, I may have gotten those boogers our of only one ZF 
without having to drill at least one.  A real PITA.

So, change the bolts with the diff in the ZF

Good luck
JT