motor mount bolts nuts that hard to find?

[tparker]

I'm in need of some motor mount bolts for a 340. I figured this wouldn't be that hard. I looked around and no one seems to carry them. The bolt seem easy enough to find, a grade 5 1/2 20 tpi. I found some were in a box 0f 100. LOL I should be able to find some locally. BUT the nuts seem to be a different story. They appear to be locking nuts which isn't common apparently. Most seem to have nylon inserts. Really didn't think it would be an issue.

Any thoughts? What do you all use and where do you get them?

[rjhjr]

Try AMK Products.

[tparker]

Hey, thanks!

I found them, and reasonably priced too!. Thanks.

[Mrbill426]

Are they not pinch nuts?  I would think a place like Ace Hardware or Tractor Supply would have them.

[tparker]

Not sure, I lost mine. LOL. I'll give it a look though. Thanks for the heads up

[moparroy]

Mine is a 360 - but I believe they use the same - maybe double check your size? I make them to be 7/16" x 20 NF x 1.5".
When I took mine apart some years ago one mount had 7/16 fine and one had 7/16 course which I assume had been replaced somewhere on the line.
I plan to order new ones from AMK - probably replace them all - they list bolts B-11619 as Chrysler engine mount brackets and nuts B-11506 as Mopar 6026750 engine mounts and starter. And those nuts are center lock type and 7/16 x 20 fine thread. Both conveniently available in 3 paks.
Looking in the '71 parts book 6026750 is listed as the nut for 340 motor mounts - actually all but 426.The AMK Chrysler cross reference number 181670 on the bolts does show in the parts book as well under standard parts but I could not find the application reference
And yes I found it hard to impossible to find a local source for these in grade 5 or SS - or any grade for that matter.

[tparker]

I found them at AMK and I might pick them up.

I also went to a local Tractor Supply Co and their bolt section was in sad shape. I am guessing covid supply issues... I hope. 3/8, 5/16 where almost non existent. They didn't carry much of the 7/16 nuts, bolts, and washers. I did find a set that are course thread 14 tpi i believe. They didn't have any lock nuts for that size. I think they only had the nylon inserts anyways. I picked up a few regular nuts and luckily the only washer they had were lock washers. I'll give that a go for now so I can get the engine in. I'll replace them shortly.

[rjhjr]

Fastenal is another source for fasteners.
https://www.fastenal.com/product/fasteners/nuts/600072?categoryId=600072&level=2&isExpanded=true

[tparker]

Awesome, thanks!

[ply64post]

I'm in need of some motor mount bolts for a 340. I figured this wouldn't be that hard. I looked around and no one seems to carry them. The bolt seem easy enough to find, a grade 5 1/2 20 tpi. I found some were in a box 0f 100. LOL I should be able to find some locally. BUT the nuts seem to be a different story. They appear to be locking nuts which isn't common apparently. Most seem to have nylon inserts. Really didn't think it would be an issue.

Any thoughts? What do you all use and where do you get them?

tparker

Here is some information from Dave Wises E/Body fastener book.

                                Jeff

https://www.boltdepot.com/Product-Details.aspx?product=14949

[Burdar]

I would think a nylon lock nut would be fine unless you are doing an OE type restoration.  Nylon inserts are usually good until 250 degrees.  I don't think a motor mount nut will get anywhere close to that.

[tparker]

@ply64post Thanks. I got that book not too long ago. Wish I got it earlier. But yeah, that is where I found the size I needed.

@Burdar I am not too concerned with 100% accurate. I just thought this would be an easy, not like looking for a 340 air cleaner or anything. LOL. AMK sells them for $50ish. Tractor Supply Co doesn't seem to carry the fine thread. I will try a local fastenal this week or next. I got a set of course thread bolts which should be fine.