Screw, weld 5/16-18NC X 5/8"

4x4M38 · Post by **4x4M38** » Sat Feb 06, 2016 6:24 pm

Any suggestions for a common replacement
for this!

Standard hex screw with part of the head
ground down? Carriage bolt with the head
ground down?

Others?

OKCM38CDN · Post by **OKCM38CDN** » Sat Feb 06, 2016 10:23 pm

Check out a company called Restoration Specialties... in Pennsylvania...

They carry weld nuts...

Bretto · Post by **Bretto** » Sun Feb 07, 2016 6:51 am

You can buy them online but that doesn't help if you need it asap.
A carriage bolt should work though. I can't remember, but where does that live on the Jeep?

4x4M38 · Post by **4x4M38** » Sun Feb 07, 2016 12:41 pm

There are three in the firewall in that indentation
that the left air cleaner bolts to.

4x4M38 · Post by **4x4M38** » Sun Feb 07, 2016 12:43 pm

Can you weld to a carriage bolt?

I know high tensile bolts are a no-no.

Bretto · Post by **Bretto** » Sun Feb 07, 2016 1:34 pm

They will weld just fine. Just watch out for zinc fumes.

Post by **wesk** » Sun Feb 07, 2016 1:59 pm

These three guys on the left side of the firewall?

This is what you need for that half of your firewall:

4x4M38 · Post by **4x4M38** » Sun Feb 07, 2016 3:57 pm

Yes Wes,
Those are the bolts/screws I need.

I would prefer not to have to replace the firewall.
1. Cost
2. No telling what it would take to get it in
3. No telling how long I'd take to get it back together.

Other than Bubba holes, and the corroded portion by the box,
the rest of the firewall is in decent shape. John and George
were checking to see if they had pieces they could supply,
but my guess is they are all bad in that spot or too good a
firewall to cut up.

So I'm doing it the hard way. Just worried I won't get the bolts
and so forth back in their proper places, but I'm trying....

Post by **wesk** » Sun Feb 07, 2016 5:19 pm

That blue jeep is mine 3 years ago getting a 2/3 rds firewall replacement and a 1/3 rd dash replacement because some Bubba had chopped the firewall up for a V8 installation.

The finished jeep is in this album:
http://www.willysmjeeps.com/v2/modules. ... php&page=1

This is what the dash looked like when I started.

This was the firewall when I started.

I had a spare cowl assembly and a spare firewall to help with the repairs.
The OD firewall in the photo in my last post.

The dash cutout is complete and ready for the patch panel.

Patch plate tacked in.

Firewall cutout ready for patch panel

Patch panel tacked in.

4x4M38 · Post by **4x4M38** » Sun Feb 07, 2016 6:16 pm

I guess I should stop whining. That is a Herculean effort, Wes.

None of those firewalls have the screws for the filter like mine does.

Just more details I have to make sure are in the right place.

Making a little progress and some pics to follow.

Post by **wesk** » Sun Feb 07, 2016 8:20 pm

The blue & the tan firewall both had the weld in screws 3 ea. They are shown with nuts on them on the blue one.

Note: that is did not use the right 1/3rd of the tan firewall in my repairs!!!!!

4x4M38 · Post by **4x4M38** » Sun Feb 07, 2016 10:23 pm

Wes,
I have four 10-24 screws welded to the firewall.
They are paired, vertically under the air cleaner.
My firewall indentation has a j-shape down
and to the right and the left two 10-24 screws are
in the bottom of the leg. I assumed they were for the
radio filter.

4x4M38 · Post by **4x4M38** » Sun Feb 07, 2016 10:37 pm

Here is the cowl view of the right side. Note Bubba termites have had their day, along with battery acid and fumes. Its paper thin and worse in the bad areas.

http://willysmjeeps.com/v2/modules/gall ... ewall.jpeg

Note the indentation at lower right with two 10-24 weld screws, and the main indentation at left, with the J-portion at the bottom. Two more 10-24 weld screws are there as well. All face thread forward into the engine compartment.

You can also see the heads of the two left 5/16 weld screws for the left mount. Our friend took care of the third one when he made the hole for the in cab air filer.

In the photos of early firewalls I do not see this feature, although I do not have Ryan's book.

Post by **wesk** » Sun Feb 07, 2016 11:11 pm

That feature only appeared on the first 10,598 M38's (or thru sn MC20599). I would guess the factory engineers issued a change to the early firewall drawing at that point deleting those four 10-24 screws. The early firewall continued in service until about MC34151 Sep 51.

4x4M38 · Post by **4x4M38** » Mon Feb 08, 2016 8:29 am

Thanks for the pics. Hard to believe all of that fits behind the air cleaner.

Yes, I knew about moving deleting the filter. Thing is, it was more than just deleting the screws. It was probably a new firewall. The 10-24 screws were welded in an indention just like the 5/16" screws, and that indention is not noticeable in the early firewall photos I've seem marked as such. I originally thought the indention was for strength, but after looking closer realize it was for clearance for the cowl battery box. I guess the screw heads would have been an issue protruding into the cowl.

I have MC11481. I believe Aaron has one within a few hundred of mine, and below the change. Wonder if we can get him to shoot a photo of his firewall.
Maybe someone else with a unit below MC20599 can shoot a photo of their firewall if original.

Take care,