Rear motor mount bolts

[lonejacklarry]

I'm using a '52 truck bellhousing in my '54 C1B6 in order to use a T-5.  These are the mounts that mount on the side of the bellhousing with a bracket and fit another bracket attached to the frame.  In between all of this are rubber pads.  My question:  what size bolts are utilized to hold all of this together.  I have a '54 shop manual but it only has information on the later bellhousing.

 

Thanks, in advance, for your help!

[JBNeal]

The rear motor mount bolt should be 1/2 7/16" x 3-1/2".

 

The bellhousing bracket bolts should be 1/2" x 2-1/2" but with a shank long enough to go through the casting and bracket.  I was able to source what I needed from a local bolt supplier, but ya might need to get a longer bolt to get the right shank, may or may not need to trim off excess...or use extra flat washers as spacers.

Edited May 5, 2021 by JBNeal
revised information

[lonejacklarry]

Thanks very much.

 

[The Oil Soup]

I’m right in the middle of changing out my tired original motor for a fresh rebuild. The rear motor mounts have a piece of tubing joining them which mics out at 0.450” id x 2.500”+/- so I believe the bolt is 7/16”. The larger pad on the top, smaller pad on the bottom with the large washer underneath. My truck is a ‘53 but all the casting dates on the motor and trans are ‘52.

[JBNeal]

Yep, that bolt should be 7/16"...I only eyeballed the '52 rolling chassis and it has gr.8 bolts in there, which should have been a clue that something was not right...crawled under the '48, '49, '51 and '53, and they all have 7/16" bolts...sorry for the confusion, I'll blame it on the chigger bites in unmentionable places that are slowly driving me nutty ?

[lonejacklarry]

On 5/4/2021 at 8:55 AM, The Oil Soup said:

 The larger pad on the top, smaller pad on the bottom with the large washer underneath. 

 

I guess I don't understand where the washer goes.  Underneath what?  Thanks.

 

[Plymouthy Adams]

the large washer is near the nut...this displacement washer prevents the nut from wanting to pull into the center of the rubber mount.  Did your mount set come with an added thin rubber washer...this is for the left mount only.

[lonejacklarry]

I have a rubber washer.  Thanks for the information.

 

[The Oil Soup]

Here are all the pieces put together except for the mount on the frame. The tube that runs inside the rubber pads prevents the bolt from over compressing them and allows the nut to cinch the lock washer. I’m not aware of any rubber washer in the assembly.

[Plymouthy Adams]

I am not sure if the truck had the other washer that fitted on the left mount as did the cars.....but...they would lift in the same manner under acceleration/torque just the same...may be the very difference in the ear it affixes.  

[Merle Coggins]

Trucks use rubber isolators top and bottom on both sides. 

 

Edited May 15, 2021 by Merle Coggins

[The Oil Soup]

That looks a little different than mine in that the bolt goes in from the bottom and has a castle nut and cotter pin on the top.