rustytoolss
Well-Known Member
The 5/16" threads for my thermostat do not feel good/ might strip. Can I enlarge the thread size to 3/8" without creating a problem ? Will they have enought material to tighten correctly ?
Yeah. I've never seen that before.T stat bolts are 5/16??
stock 318 polyWhat intake manifold is it?
No 5/16 NCstock 318 poly
Thanks, I just checked a Drill Tap chart, 5/16" is the correct drill size for a 3/8"-NC thread. Did a test with a 5/16 nut, you can tap it to 3/8-NC no problem.To answer your question...i have done that and it worked fine.Are there other options...absolutely.
You will probably have to drill your thermostat housing and enlarge the gasket holes. What a pain.Thanks, I just checked a Drill Tap chart, 5/16" is the correct drill size for a 3/8"-NC thread. Did a test with a 5/16 nut, you can tap it to 3/8-NC no problem.
You will probably have to drill your thermostat housing and enlarge the gasket holes. What a pain.
Exactly. What a pain modifying everything to make it work where a thread insert will fix it right.3 minutes tops.
No pain killers required.
I would take the extra time to do it right with a Heli-Coli set though.
MAke sure the threads are clean all the way down the hole. It's a cast iron manifold so it's pretty tough and forgiving. I use a pocket screwdriver to loosen the gunk in the bolt holes then blow them out with compressed air than follow up (carefully) with a thread chaser. I don't use a tap. You might have enough good threads for a stud and some Locktite. (might) Clean the threads on the bolt if you are reusing that.The 5/16" threads for my thermostat do not feel good/ might strip. Can I enlarge the thread size to 3/8" without creating a problem ? Will they have enought material to tighten correctly ?