bonnettoboot
Active Member
- Joined
- May 21, 2006
- Posts
- 25
- Reaction score
- 0
I can't beleive it has been 10 months since I visited. This is an interesting tale that I thought might be worth posting here. I would welcome any comments. Bill Brady
To get you away from these nebulous electronic problems I thought you might enjoy
wrapping your minds around this tranny problem. A Customer of about 2 years called
about a year ago, the vehicle was vibrating a lot and asked what was. A few weeks
later he called and said it was bad he was coming in. He was about a mile from us
when the front drive shaft came off. Luckily, little damage was caused and we refitted
it. A week ago, he again called, a bad vibration again he was coming in by tow
truck. We put it up and found the drive shaft loose again, also the front damper
was hanging on 1 bolt, Refitted and tightened everything and drove it, It made
a strange banging sound on starting and at 2000 the vibration was severe, over that
it was much less, at idle it was smooth and quiet. We pinpointed the source in
the transmission the btrake drum was actually shaking. so off came the T/fer box
cover, nothing seemed wrong! Ran motor again without T/Box and it was still there
but now seemed to be in the transmission/bell housing. We decided to pull out the
whole unit. In the meantime I looked up alldata and was surprised to find TSB 86/08/01/NAS
regarding balance weight on the flywheel- this vehicle was supceptible-. Looked
and could see NO balance weights. Aha, we thought, they had obviously come off
and caused the noise and vibration etc, Out with the unit. Every bolt associated
with the unit was loose. First surprise, it had had a used unit fitted. But there
was no sign of weights on the flywheel at all? Now we pulled off the flywheel as
the flex plate looked cracked, it fell off in peices, from the wear marks it had
been totally broken for a long time. Was this the cause or the result? Then I found
TSB 44/01/00/NAS, this describes various spacers for the various engines. For our
VIN the one fitted was correct 7mm. We ordered a new flex plate and sent the Convertor
out for checking. In the meantime I was intrigued by the fact that this flex plate
had been able to drive the vehicle even thopugh it was totally broken, so I decided
to look a bit closer. I'd noticed that the plate was a little conical but took
no notice, UNTIL we got the new plate, there was almost 1/2" difference back
to back, as if the old plate had been bent in position, We fitted everything together
loosely and sure enough the plate was being pushed back about 3mm when tightened
up. In fact if it had the 4mm spacer it would be correct!! It now seems that this
trans was from an earlier model which had the 4mm spacer, the installers did not
realize the difference and fitted it with the 7mm one, belling the flex plate as
they tightened it. The vibration was always there and gradually got worse until
the plate broke and created an unacceptable vibration. Out of curiosity I got a
used flywheel from a local yard to check if it was different, it was exasctly the
same EXCEPT, it had a balance weight screwed into it JUST 1. Now I had presumed
that the earlier units had no balance wights as the flywheel seems to have the balance
adjustment cast into it. We have ordered the spacer and new seals, and hope we are
right! But i'm concerned about the balance weights, should it have them or not?
Can anyone out there add anything to this? Bill Brady
To get you away from these nebulous electronic problems I thought you might enjoy
wrapping your minds around this tranny problem. A Customer of about 2 years called
about a year ago, the vehicle was vibrating a lot and asked what was. A few weeks
later he called and said it was bad he was coming in. He was about a mile from us
when the front drive shaft came off. Luckily, little damage was caused and we refitted
it. A week ago, he again called, a bad vibration again he was coming in by tow
truck. We put it up and found the drive shaft loose again, also the front damper
was hanging on 1 bolt, Refitted and tightened everything and drove it, It made
a strange banging sound on starting and at 2000 the vibration was severe, over that
it was much less, at idle it was smooth and quiet. We pinpointed the source in
the transmission the btrake drum was actually shaking. so off came the T/fer box
cover, nothing seemed wrong! Ran motor again without T/Box and it was still there
but now seemed to be in the transmission/bell housing. We decided to pull out the
whole unit. In the meantime I looked up alldata and was surprised to find TSB 86/08/01/NAS
regarding balance weight on the flywheel- this vehicle was supceptible-. Looked
and could see NO balance weights. Aha, we thought, they had obviously come off
and caused the noise and vibration etc, Out with the unit. Every bolt associated
with the unit was loose. First surprise, it had had a used unit fitted. But there
was no sign of weights on the flywheel at all? Now we pulled off the flywheel as
the flex plate looked cracked, it fell off in peices, from the wear marks it had
been totally broken for a long time. Was this the cause or the result? Then I found
TSB 44/01/00/NAS, this describes various spacers for the various engines. For our
VIN the one fitted was correct 7mm. We ordered a new flex plate and sent the Convertor
out for checking. In the meantime I was intrigued by the fact that this flex plate
had been able to drive the vehicle even thopugh it was totally broken, so I decided
to look a bit closer. I'd noticed that the plate was a little conical but took
no notice, UNTIL we got the new plate, there was almost 1/2" difference back
to back, as if the old plate had been bent in position, We fitted everything together
loosely and sure enough the plate was being pushed back about 3mm when tightened
up. In fact if it had the 4mm spacer it would be correct!! It now seems that this
trans was from an earlier model which had the 4mm spacer, the installers did not
realize the difference and fitted it with the 7mm one, belling the flex plate as
they tightened it. The vibration was always there and gradually got worse until
the plate broke and created an unacceptable vibration. Out of curiosity I got a
used flywheel from a local yard to check if it was different, it was exasctly the
same EXCEPT, it had a balance weight screwed into it JUST 1. Now I had presumed
that the earlier units had no balance wights as the flywheel seems to have the balance
adjustment cast into it. We have ordered the spacer and new seals, and hope we are
right! But i'm concerned about the balance weights, should it have them or not?
Can anyone out there add anything to this? Bill Brady
