MTFCA Forum

Radiator support rod - missing.
I re-threaded the radiator and found it to be 5/16"-24.
Some time ago the rods for the parking brake looked rusted out and for safety, I replaced them.
As it is they are the same diameter and thread per inch.
So, I ran a die on the end and cut the other end to length.
A large carriage bolt sacrificed its head, getting a weld to the end of the rod.
The other parking brake rod I cut for the hood center connection which was also missing.
I think they will both get painted either black or dark green.

The rod is 5/16" diameter where it engages with the radiator. It needs a lock nut to stop it working on the thread. The other end at the firewall is 3/8" fine thread. It takes a plain hex nut which sandwiches it at the fire wall. This end must be anchored to stop it moving in the 26-7 firewall bracket or where it goes through either a wood or steel firewalls on earlier cars.

Allan from down under.

I can add a 5/16" fine thread nut on the radiator end.

The firewall side has no thread at all. I merely ran a bead all around the bevel cut and ground it square so that it could not turn.

To Do:
It sounds like I can cut the rod shorter at the firewall, weld on a carriage bolt 3/8" (with a nut already in place).

It sounds like I can cut the rod shorter at the firewall, weld on a carriage bolt 3/8" (with a nut already in place).

You shouldn't need a nut already in place. It should slip over the 5/16" part of the rod. In fact, on pre-26 Fords it has to, because the rod is inserted through the firewall from behind.

Home made support rod. I didn't have a lathe to get the 5/16" part exactly even.
The 3/8'" part is round, not a carriage bolt, because the rod has to turn to adjust the radiator position. If I remember correctly, I made the head with a washer.

The firewall end needs to be anchored. Otherwise the end you have stopped from turning is still free to move fore and aft, either within the bracket on an improved car, or through the firewall on any other. The rod is meant to hold the radiator in a steady position, and make the hood fitting constant.

Allan from down under.

Steve's design is correct, the original rod in my '26 coupe is made the same way, just with functional threads all the way up to the head b/c the '26 coupe firewall bracket is thinner. My coupe also has a lock nut on the radiator end, which prevents the rod from vibrating and wallowing the threads in the radiator socket. FWIW, jb