Head bolts / studs

I can imagine that you might have problems with helicoils if you stay with the factory 28 thread bolt. The helicoil would have a much finer thread. Part of the reason I went to a 14 thread bolt was the possibility of having trouble with this finer thread. I haven't had any problem in 7 years.

Tom,
To the best of my knowledge the factory never used studs in place of the head bolts. For the repairs you can go back thru this Fourm and find several posts of the repairs.

For using Helicoils I personaly don't like them> I've had problems with them pulling out and leaking. I perfer full threaded inserts (ez-loc) They work well in the Cord engine (watch some engine the holes at the bottom of the head are close to the edge). They are coated with Loctite on the external threads so the stay put and don't leak. Also if they ever strip out they are easy to remove and replace.

Jim

I bought the remainder of an old fellows Cord stuff a number of years ago. I had seen some repairs he had done with studs and didn't like the way it looked. When I rebuilt my engine I chose to tap out each bolt hole to take helicoils. I went 7/16" and 14 thread bolts and have had no trouble. It was a lot of work but feel it was worth it.

Hi Tom,

The threads were stripped or stretched on many of the head bolt openings in the block on my Cord, and as the engine was rebuilt custom oversize-on-one-end studs were made and installed in drilled-out and tapped head bolt holes in the block. Not factory, but more reliable than inserts.

You have a photo of the engine in my car--perhaps that prompted your question. Anyway, blow up the photo and take a look.

I remember that as a boy I was allowed to engage the threading lever on the old South Bend lathe to cut threads in the new studs. This was truly a life-guiding experience as I have been around metal working machinery my whole life.

--Tom

Hi,

Were studs ever used in place of head bolts from the factory? Were studs ever used as part of a common repair for stripped thread (helecoil +stud)