gearbox screws

PostPost by: gino1 » Tue Apr 11, 2023 3:21 pm

Can anyone tell me the size of the 4 bolts that hold the gearbox onto the bellhousing ?

Thanks
Gino
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PostPost by: types26/36 » Tue Apr 11, 2023 4:06 pm

According to my book they are 7/16 unc x 1"
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PostPost by: 512BB » Tue Apr 11, 2023 8:18 pm

Off the top of my head, 1" seems to short to me, but could be wrong. By the time you have got a washer and a spring washer on there, there wont be much thread left. More like 1 1/2".

The picture got me all confused. Thinking of the bellhousing to block.

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PostPost by: gino1 » Wed Apr 12, 2023 9:07 am

Excellent.. thank you Leslie.

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PostPost by: promotor » Wed Apr 12, 2023 9:36 am

gino1 wrote:Can anyone tell me the size of the 4 bolts that hold the gearbox onto the bellhousing ?

Thanks
Gino


As Brian says, they are 1" long - that is the "under head" measurement.

DSC03876.JPG and


These were the original length bolts used in the wide-ratio gearboxes with a large size 4th gear on the cluster - if you used anything longer than that the one bolt that goes through to inside of the gearcasing would hit the cluster gear as the larger gear is visible through the hole.
The threads don't need to be any longer as there' only so much female thread available.
All gearboxes thereafter whether wide/semi/close ratio used the same 1" long bolts.
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