fot
[Top] [All Lists]

[Fot] Urgent! TR4 Detroit Locker problem, locks wheels going backwards

Subject: [Fot] Urgent! TR4 Detroit Locker problem, locks wheels going backwards
From: timmmurphh at gmail.com (timmmurphh at gmail.com)
Date: Mon, 11 Sep 2017 10:02:04 -0500
We have a race this weekend at Elkhart Lake.  Just put engine/trans back in 
car.  Test drove on road.  In trying to backup, both rear wheels are locked 
solid.  Trying to reverse just stalls engine.

 

Last time the car was on the road was in May at Gingerman.  No problems.  Since 
then been sitting up in the air on the lift getting ?air time? while new block 
being machined.

 

Very puzzling how sitting up in the air would cause diff problem.  Car now has 
more ?air time? on the lift than track time!

 

Have taken cover off diff, everything looks okay.  No pieces of metal.  Gear 
oil pretty black, has been in there about 10 years.

 

Both ring and pinion look okay.

 

Put fresh Reline gear oil in and buttoned up.

 

Tried again on lift.

 

Turning drive shaft (trans in neutral), can turn both forward and backward.  
Both wheels turn.

 

Try in driveway, same result, cannot backup, trying just stalls engine.

 

We could get the car back on the lift by driving forward and turning around in 
the cul-de-sac by the house.  Did donuts in the cul-de-sac to see how diff 
reacted.  Left two nice black marks in the donut.  Accelerated forward and the 
diff was unlocked because there is just one long black streak.  I?ll have to 
ask Ryan how it sounded and acted.  He was driving to do that.

 

When car back on lift, same thing, both rear wheels locked up when trying to 
turn backwards last night.

 

We can make diff lock and unlock by holding one wheel and turning the other 
wheel forward.  Not sure about specifics, wasn?t taking notes.

 

So far, we can make it work, sometimes on the lift, by turning the driveshaft.  
But once on the ground we cannot make if work under power.  We could push the 
car backwards out of the shop but once we drove forward and tried to back up 
the wheels were again locked.

 

Any insight or suggestions will be much appreciated.  Is this a typical failure 
mode for a Detroit Locker?  Any suggestions for further examination and 
testing?  The last time we drove the car back into the shop to put up on the 
lift we heard a pretty loud ?clicking? noise from the diff.  Never noticed this 
before but wasn?t necessarily listening for it before either.

 

Very interesting, I just tried turning the wheels with car on lift and can turn 
both wheels, individually, both forward and backward, no problem.  It is now 
not locked up in the backwards direction.  When turning one side the other side 
also turns in the same direction.  It?s acting like the diff is locked up in 
both directions and the wheels turn in both directions.  Last night, the last 
time we tried turning the wheels backwards it was locked up.  Maybe it only 
works up in the air!!!!

 

Very puzzling!!  I am not at all familiar with how the Detroit Locker works.  
It was the one thing on the car we never had to worry about.  I guess I?ll 
learn something now?

 

Tim and Ryan Murphy

Murphy?s Law Racing  (very appropriate today!)

1961 TR4 #317 BRG

-------------- next part --------------
An HTML attachment was scrubbed...
URL: 
<http://autox.team.net/pipermail/fot/attachments/20170911/7f9f71b5/attachment.html>

<Prev in Thread] Current Thread [Next in Thread>