Stripped Head Bolt in 79 2F - How have others repaired successfully?

[davework]

Machine shop called me today and let me know there is a stripped head bolt thread in my 2F block from my 79 40.

I did a search and found one previous thread with some links suggesting thread repair kits, but I cannot locate those kits in stock anywhere now, and the machine shop is also skeptical to use a brand unknown (to them) in a head bolt repair.

Other than locating and vetting a 13mmx1.75 thread kit, got the same options as outlined in that thread:

1. Tap and insert a larger size inch or metric bolt.
2. Tap and insert a 12mm metric bolt.

Rather than take material from the block to accommodate a larger bolt, they are recommending a 12mm insert, especially given the relatively low 90ftlb torque. They are more hesitant to take material from the block than using a smaller head bolt. One reason is because metallurgy is so much better these days a quality smaller head bolt should be more than adequate.

I am curious if anyone has successfully repaired one of these using any of these methods and has put some miles on? Or if one of our shop vendors has a preferred method to tackle that has proven suitable?

Or does anyone have a 13mmx1.75 thread repair kit that they would sell me?

 

[shawnfj40]

Tell them to use the proper time sert and you can't go wrong.++ TIME-SERT Official Threaded inserts for stripped threads, blown out sparkplugs,

 

[honk]

Time-Serts are the way, and way better than helicoils, IMO.

 

[zebrabeefj40]

Timeserts don't come in the right thread. I did find Recoil sold a kit in the right thread but didn't find anyone that had one. Recoil makes inserts like the Helicoil brand product and are just as good - I use either in my machine shop.

FWIW: Helicoil inserts are specified by Cummins in some of their aluminum castings. I worked for a foundry that made castings for Cummins, then machined them, then installed Helicoils, then assembled the castings into finished aftercoolers for excavators. IMHO nothing wrong with a properly installed Helicoil. We used Timesert inserts too - once holes got too damaged to Helicoil.

Nick

 

[Spike Strip]

You're going to have a Hell of a time finding one in the US.

PowerCoil 3520-13.00K M13 x 1.75 Thread Repair Kit

You might call Martin Davidson, in Reseda, CA and ask what he does. He used to build MAFs 2Fs and I know he's repaired a number of 2F blocks.


Martin Davidson's Automotive Machine Shop | Engine Machine Shop | Auto Machine Shop

 

[Fast Eddy]

You should be able to find another 2f block for approximately free. I have one if you want to come get it.

 

[FJ40Jim]

^ What he said. ^

 

[davework]

Ordered a Recoil Kit from UK for about $65 shipped. I'll have extras if anyone runs into this issue down the road. I know another block would've been possible, but I am partial to keeping mine intact if practical. Thanks for all the responses. PM me if you need a Recoil Kit in 13mmx1.75.

 

[White Stripe]

I have used a helicoil for a stripped head bolt hole. Worked great. Time seats are too expensive for me, and I have never had a helicoil fail. When I install a helicoil I often put some Locktite on it before I spin it in b4 I thread the helicoil in. Head studs would reduce stress on the block holes, but I've never heard of anyone using studs on a 2F.