79 Spitfire Pot Repair

mikehjd · Post by **mikehjd** » Thu Jan 01, 2009 3:31 am

I started my newest addition today a 79 spitfire. It fired up perfect and when I opened the shop door to take it out for a test ride I hit the gas and heard a pop. The head gasket blew out, when I took the head off someone before had stripped the 2 front studs out and replaced them with 2 bolts. The bolts were just holding by a thread and by the looks of the gasket it had been leaking for awhile. Has anyone had any luck with a heal a coil or anything to repair the threads?

speedy295 · Post by **speedy295** » Thu Jan 01, 2009 8:24 am

A heilicoil should fix this no problem. Another posible fix, allthough not as nice, is to use a neckdown stud. Say the stud was an 8mmx1.25m you would drill it out and tap it to 10x1.5, and then thread in a stud that had one end a 10x1.5m and the other end a 8x1.25

JDT · Post by **JDT** » Thu Jan 01, 2009 12:01 pm

If you have the room you can also drill and tap the hole deeper and use a longer stud.
This can be touchy with a L/C jug as there are coolant passages that might not offer the required clearance but with a F/C or F/A you may be fine.
Stepped studs and regular studs can be purchased from MCMaster-Carr.

3liquifires · Post by **3liquifires** » Thu Jan 01, 2009 12:53 pm

I think I would try the helicoil, I have had good luck with them in the past. Happy New Year and good luck Travis

Farrel · Post by **Farrel** » Sun Jan 04, 2009 11:49 pm

I also have a couple of '79 Spitfires, and on one of them I had to replace the 2 front studs which had pulled out of the pot. I drilled the holes out one size bigger on the pot and the head to 7/16 and used bolts that size with the head cut off to make the studs. Tapped the hole with correct threads, tightened them up and it worked fine. Maybe not the most recommended fix, but I have about 100 miles on it like that and it still works perfect. Parts are not exactly in great supply, so I figured I'd give it a try.

Farrel · Post by **Farrel** » Sun Jan 04, 2009 11:52 pm

Just a note to my previous post... One of the holes already had a helicoil in it which had let go, so I pretty much had no choice but to drill bigger.