Loose Carburetor to Manifold studs

Farmall Cub Forum -- Questions and answers to all of your Cub related issues.

Moderator: Team Cub

Forum rules
Notice: For sale and wanted posts are not allowed in this forum. Please use our free classifieds or one of our site sponsors for your tractor and parts needs.
Bob McCarty
Team Cub
Team Cub
Posts: 8986
Joined: Tue May 25, 2004 8:02 pm
Zip Code: 80501
Tractors Owned: Cubs, MH Pony, Shaw, Allis G, 1934 Silver King, JD LA and LI, Gibson D, David Bradley Tri-Trac
Circle of Safety: Y
Location: CO, Longmont

Re: Loose Carburetor to Manifold studs

Postby Bob McCarty » Thu Dec 06, 2018 4:37 pm

If you can get by until next spring, bring the carbs to the Barnyard Bash (or another Cubfest) and get them fixed there.
"We don't need to think more,
we need to think differently."
-Albert Einstein

lyle11
Cub Star
Cub Star
Posts: 166
Joined: Mon Nov 24, 2014 12:09 am
Zip Code: 44236
Tractors Owned: 48 FCub
55 Lowboy
60 Lowboy
Allis Chalmers B

Re: Loose Carburetor to Manifold studs

Postby lyle11 » Sat Dec 08, 2018 9:25 pm

Since one side was already drilled out to 5/16”, I figured I would try a cheap fix that might be better than filing off the side of a nut and running a bolt through. I bought one of these Pronged Tee Nuts at Menards. It has a 1/4-20 thread and the OD is 5/16”. It says zinc on the package so I assume it is grade 2 steel.

I cut off one side of the flange and bent the prongs a little so they rest on each side of the carburetor body. Plus, underneath the cut off side rests against the carb body and should hold it secure from rotating while the stud is tightened down. I realize the stud and threaded insert can drop down through the hole if pushed, but it fits fairly snug and the flange will get pulled up tight when the manifold side is tightened.

Certainly not as good as a helicoil but it will let me use the proper studs and provides more threads to hold it than an open hole with a nut underneath. Plus with the tee nut shaft in the hole it should center the stud better than running a 1/4” bolt through a 5/16” hole. Since I don’t have any Heli-Coils, and with the oversized hole, I would have to do a larger Heli-Coil before the 1/4-20 so that would have been close to $40 for 2 kits.

I’m gonna order the studs from TM. I might have to file a little material off the top of the Tee nut. I realize it is not real strong metal but seems like it would be stronger than the carburetor metal. I think the tee nuts come in Grade 5 but I didn’t see them at the store. Not sure if I should do the same thing on the other side since the threads are worn out, but it has not been drilled out. Depending how much of the stud protrudes I might be able to put a nut on the bottom and preserve the hole for a future Heli-Coil job.

A27FC463-F323-48E8-967A-1624B8D2ED5E.jpeg
A27FC463-F323-48E8-967A-1624B8D2ED5E.jpeg (62.69 KiB) Viewed 80 times

8EF2E338-FDD2-41BC-8538-C1B3872AA4CC.jpeg
8EF2E338-FDD2-41BC-8538-C1B3872AA4CC.jpeg (64.15 KiB) Viewed 80 times

EF5DBB31-D735-4215-968F-E9C674AE8FBE.jpeg
EF5DBB31-D735-4215-968F-E9C674AE8FBE.jpeg (38.2 KiB) Viewed 80 times

Bob McCarty
Team Cub
Team Cub
Posts: 8986
Joined: Tue May 25, 2004 8:02 pm
Zip Code: 80501
Tractors Owned: Cubs, MH Pony, Shaw, Allis G, 1934 Silver King, JD LA and LI, Gibson D, David Bradley Tri-Trac
Circle of Safety: Y
Location: CO, Longmont

Re: Loose Carburetor to Manifold studs

Postby Bob McCarty » Sat Dec 08, 2018 10:32 pm

lyle11 wrote: Since I don’t have any Heli-Coils, and with the oversized hole, I would have to do a larger Heli-Coil before the 1/4-20 so that would have been close to $40 for 2 kits.

Just for future reference, you can't thread a heli-coil into a larger heli-coil as the threads wouldn't match between the two. The heli-coil requires the special STI tap which is different than a standard tap, thus different threads.
"We don't need to think more,
we need to think differently."
-Albert Einstein


  • Similar Topics
    Replies
    Views
    Last post

Return to “Farmall Cub”

Who is online

Users browsing this forum: Ken (48 Cub) and 4 guests