Bishop75

I plan to replace the head gasket in my 90 Cherokee and I have been told that I will have at least one head bolt. I need to know where can I get the proper bolts for my Cherokee? Is there a set some where out there?

Is there any one out there that can point me in the right direction?

Bishop75

At least one that will break

macgyver35

The dealership would be your best bet. Modern head bolts are designed to stretch as part of their initial torque process, so replacing the whole set with new when changing the head and/or gasket is usually recommended. Note that I didn't say absolutely necessary in every case. However, if I were going through all the trouble to change that gasket, I'd want some new, properly torqued bolts in there for insurance.

Others may give you different advice...

Radi

Or not. I always replace them. Never know what a previous Bubba with no torque wrench (but a really big piece of pipe) may have done.

BatmanXJ

Anytime I do a job like that. I always spend the little extra to do it right. Go to the Dealer and get a whole set. If it was something simple like valve cover gasket maybe not but when you go that deep you might as well do it right. I would also have your head checked while you have it out to know weather or not its gonna last. It may cost a little bit but could be worth it in the long run.

Radi

Hah. My wife says the same thing.

Bishop75

But what if the local dealership can't get a full bolt set?

5-90

"At least one head bolt" - what?

The cylinder head screws used on the 6-242 are a modification of the "torque-to-yield" type, they're good for two full torque cycles and require replacement. Replacing them after one won't hurt any, tho.

I've not had trouble with head screws breaking on the second torque cycle - but if the heads are painted, I won't reuse them.

Per FSM, you're supposed to paint the heads of the screws on the first reuse - and replace them if they're painted when you pull them out.

You can go to the dealership, but you can also order them in the aftermarket - I think headbolts.com carries them. Two sizes of head screw were used on the AMC six (including the 6-258!) - they're threaded either 7/16"-14 or 1/2"-13. Get the 1/2"-13 screws for the 6-242.

Markings on the head show as standard SAE8 pieces, but I have yet to verify this. I'd like to see if they can be replaced with COTS pieces (good-quality SAE8 hex head capscrews or socket head capscrews,) but I've not yet been able to experiment with this. However, I'm sure that the spec of 110 lb-ft given is below what a standard SAE8 screw will tolerate (and, if I used standard SAE8 screws, I'd replace them each time out of hand anyhow.)

cruiser54

Never had one break yet on a 4.0 since 1987.........Who is telling you that?

Also, you can re-use those headbolts once.