1970 134 Fhead Head Gasket Replacement

Thing is, they may actually be expected to stretch, and recover, within certain elastic limits over thousands of heat cycles, and to protect the head gasket by doing so.
A bolt which undergoes plastic deformation never recovers fully and no longer provides adequate clamping.

Grade 8 may be more brittle than a designated head bolt with a planned resilience. Bigger numbers are not necessarily appropriate or better.

Carroll Smith's Nuts, Bolts, Fasteners and Plumbing Handbook (Motorbooks Workshop): Carroll Smith: 9780879384067: Amazon.com: Books

 

Interesting read!

 

Put all head bolts in finger tight. Then i put all head bolts in at 30lbs. Then was going for round 3 at 60lbs. All was fine until i got to bolt 9 in the tightening sequnce. i thought i snapped the bolt. it gets snug, then spins. should i get a 1/4" longer bolt? Yes I rethreaded all of the stud holes and the bolts with a tap and die set prior to starting

 

with bolt unscrewed and just sitting in hole . how much bolt is sticking above head
sounds like it helicoil time . and you got to start all over again

 

Just under a half inch. so what happened? it bottomed out and stripped at that depth?

 

"Just under a half inch"

Not bottomed, unless it snapped off at the tip. Unlikely with Grade 8.

Just the opposite. Half an inch ain't near enough thread engagement length. Stripped the block threads with the hardened bolt threads.

Adding another ¼" won't make it. Helicoil. AND get the right bolt length for all the other holes.

 

What is the proper bolt length?

 

Is there a sleve in the head then? Do i get a smaller bolt for the helicoil insert? i have to drill out the hole larger, then tap it, insert the helicoil, and use the same size bolts?

Ive never helicoiled anything

 

And i can reuse the gasket, right?

 

Head bolts are as Howard describes. Four and one-quarter inch long.

Part #805730 (14 of 4-¼")
Part # 801000 (1 of 1-11/16")

 

I googled the part numbers. where did you get them from? or is that the fsm bolt part #?
Can i go to a local hardware store for a helicoil?

 

1955 Jeep Parts Book

A good hardware may have helicoils, otherwise it will be a FLAPS. You'll probably have to buy several in a pack. Get the special tools too.

 

Whats a flaps? im not clever with acronyms

 

Friendly local auto parts store.

 

Wife says to buy a new motor and stop messing with this old one. i keep saying honey, eventually it will be a new motor...

 

Couldnt guess the "f".

How do i drill it out? hand drill seems like a bad idea