350 SBC Motor Mount Bolts - Which are correct?

[greywurm]

I lost a bolt for my driver side motor mount yesterday, the center bolt of stand to mount, and the passenger side is loose (might have loosened on the 5 minute return trip home).

I have done some researching and it looks like I might have been using the incorrect bolts, but I am not sure how I would get a nut on the bolt between the mount and the engine block.... it was hard enough lining up the engine to the stand to get the center bolts lined up!

Anyways, I attached the pic of the bolt I used from the 250 I6 I pulled and these ARP bolts from summit.

Would the lack of a nut on the opposite side contribute to the bolts loosening and coming out?

[greywurm]

I know... Probably a stupid question...

[michael bustamante]

no the v8 motor mounts should have a nut tacked onto them. most guys use a locktite on the bolts
those new ones look like they would be for the clamshells like on a 73 and newer half ton

[greywurm]

Originally Posted by michael bustamante

no the v8 motor mounts should have a nut tacked onto them. most guys use a locktite on the bolts
those new ones look like they would be for the clamshells like on a 73 and newer half ton

All I have been able to find so far are those ARP branded bolts or something just like it. I hate asking for someone to find a part, but I really dont know what to look for or what im searching wrong. That is what came up for my 71 year truck on summit and the local shops' sites.

[67c10rustbuket]

7/16 --14 x 1 1/4" long.

[67c10rustbuket]

The "NUT" is molded inside the rubber mount.

[michael bustamante]

I bet i have a pair. ill look and let you know in the morning

[greywurm]

There is a nut in the mount, so I guess my issue really was just that I didn't use thread locker on the bolt.

What do you suggest, red or blue?

[michael bustamante]

well youll never really have to take it back out until the motor mount or the motor itself fails so whichever is stronger

[GASoline71]

I've never used Loctite on those bolts. Never lost one.

Gary

[greywurm]

Originally Posted by GASoline71

I've never used Loctite on those bolts. Never lost one.

Gary

For what its worth, the one that came out looks like it could use a new lock washer.

[67c10rustbuket]

Originally Posted by GASoline71

I've never used Loctite on those bolts. Never lost one.

Gary

Ditto.







They are a pita to get to on the original mounts. I bet someone tightened it the best they could (not fully tightened) and it vibrated loose. I recall flipping my ratchet back and forth 100 times an 1/8 turn at a time then thinking I should have changed to the later clamshell style.