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Author Topic: Rebuild Tranny Lock Up
Little Bill Verified Driver
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Region: Colorado
Car #: 03
Year : 90
Posts: 411
Status: Offline
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I am in the process of rebuilding my 95 year model transmission and have run into a snag.

Everything was going smoothly until it came time to torque the nut that holds the 5th-reverse clutch hub in place. Once tightened above 10 lbs of torque the transmission looses neutral. No gear selected, but transmission acts as if a gear has been selected. Once a gear is selected the tranny locks up, the way it should when reverse and another gear are selected.

In trouble shooting, what I have found is when 1st gear is selected, the trans does not lock, which indicates to me that there is a problem with the assembly at the 1st gear position. However, when I loosen the assembly to check, everything appears normal.

If I tighten the nut just enough to take up the slack in the gear cluster on the main shaft every thing works perfectly. Snug at all beyond that point and the above mentioned condition occurs.
[banghead] [banghead] [help]

[ 02-12-2007, 04:49 PM: Message edited by: Little Bill ]

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Bill Hingston
SM#03
RM_Div

davew Verified Driver Made Donation to Website
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Region: chicago
Car #: 72 and ?
Year : 90 and 90
Posts: 1051
Status: Offline
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Potential, possible maybe causes:
1-2 hub clutch instaled backwards

Bent fork

Bent syncro ring, just dropping it on the floor can ruin it.

Has anything been coated. The coating may have changed the thickness of a component.

If nothing looks amiss, put the old parts back in and try again.

Hope that helps
Dave

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BERG Racer Verified Driver
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Region: NER
Posts: 241
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The dogs that engage the syncro to the slider hub are misaligned. Realign, use a wad of heavy grease to hold in place and carefully reassemble making sure nothing moves. Should solve the problem. BTW this is most typical when the trans is being assembled in a vertical fashion. Try heating the front bearing pockets and sliding the front cover over the cluster horizontally. Once it's seated and the nuts are on the you can stand it up.

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http://www.bergmotorsports.com/index.php

Little Bill Verified Driver
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Region: Colorado
Car #: 03
Year : 90
Posts: 411
Status: Offline
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First of all let me say thank you for the input I do sincerely mean it as there has been precious little response to my post.

The syncros are good and the dogs are aligned properly. I was born at night but it wasnt last night. [Eek!] [Wink]

Seriously those were the first things I checked. Im going back out to the garage now to finsh the redisassymbly will get back with more info when I have it.

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Bill Hingston
SM#03
RM_Div

Jim Boemler Verified Driver
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Region: NWR, OR
Car #: 30
Year : 1992
Posts: 8523
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Sorry about the dearth of help, Bill -- most of us haven't taken apart the trans, so we haven't got anything to add.

jim

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Just a clown

Little Bill Verified Driver
Member

Region: Colorado
Car #: 03
Year : 90
Posts: 411
Status: Offline
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Stupid is as stupid does, I found the problem.

First of all let me say never, and I do mean never, let anyone touch the guts of your disassembled transmission. Also, when assembling never assume that all is right. This is what I found after walking away from the project for a day.

There are two bearing collars that are located on the main shaft. They have roller bearing cages that support both 1st gear and reverse. These collars are very close in dimension with one collar slightly longer than the other. There is also a recess in the reverse gear collar. These collars had inadvertently been placed into the wrong gears by a buddy of mine who was playing with the parts when he was over the other day.

I assumed that the assemblies were correct since I hadnít separated the bearings from the gears. Big mistake. After tearing everything back down and finding the problem I called my buddy who fussed up, and said that he had been pulling the collar and cage out of both 1st and reverse and that he may have gotten them back in the wrong gears.

I thought I had done everything correctly by carefully laying the parts out as they came out of the gear box. But sometimes sh*t happens especially if you have inquisitive friends.

These boxes are simple and if you pay attention to detail they are very easy to rebuild

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Bill Hingston
SM#03
RM_Div

   

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