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87 2.5l head bolt torque spec

OkieXJ

NAXJA Forum User
NAXJA Member
Location
Muskogee, OK
Hi everyone,:helpme:
I am getting ready to reinstall the cylinder head onto my 87 MJ 2.5l I4. I have some conflicting information on how to torque the head bolts so I am hoping someone can clear this up for me. My haynes manual, which I understand is known to be wrong from time to time, says the following:
Torque bolts in sequence and use the following steps:
step 1: 25ft-lb
step 2: 50ft-lb
step 3: 85ft-lb except bolt 8 to 75ft-lb only.

I have an '88 FSM and it says to tighten all the bolts in sequence to 110ft-lb except bolt 8 to 100ft-lb. It doesn't mention multiple steps at all and the torque specs are obviously different than the haynes manual:confused:.

Also, the '88 FSM says to use "thread sealant" on bolt 8 and the haynes says to use teflon tape. I'm not sure what specific sealant the FSM means and I'm not going to use teflon tape. I'm leaning towards hi temp RTV.

Any help is appreciated. Thanks experts.
 
Use Loctite PST sealant or equivalent.

Now, my 90 FSM seems to have a misprint, with some confusion between bolt 7 and bolt 8:

Follow the FSM, 110 and 100 for number 8. Follow the tightening pattern, first to 22, then 45, then 1-6 to 110, 7 to 100, 8-10 to 110--note that my 90 FSM is saying bolt 7 to 100, but the torque specs following the engine section says bolt 8. It also says to put thread sealant on bolt 7. Here is the key, the bolt that passes through the water jacket MUST have the sealant, and the bolt that has the sealant will have the 100 torque.

PS--use the Haynes for sh*t paper, your life will be easier.

EDIT: did you take note of using two old headbolts and making alignment dowels as specified in the FSM? If you don't have extra head bolts you could use a couple pieces of hardwood dowel for the alignment. Their purpose is to keep you from have to monk with the head while it is sitting on the gasket to align the holes--it will damage the gasket.
 
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Thanks for the info. I plan on reusing my head bolts because everything I've read says that can be done once. I'll definitely try the dowel rod approach for lining the head up, I was wondering how I was going to deal with that. It was suprising the fsm didn't mention the multiple steps but I figured those were a must anyway. This forum is a lifesaver!
 
They are listed in the 90 FSM, not with the Torque Specs at the end of the 2.5 L engine section but in the body of the text, surprised (but not greatly) it was left out of the 88 FSM.

Good luck.
 
Hi everyone,:helpme:
I am getting ready to reinstall the cylinder head onto my 87 MJ 2.5l I4. I have some conflicting information on how to torque the head bolts so I am hoping someone can clear this up for me. My haynes manual, which I understand is known to be wrong from time to time, says the following:
Torque bolts in sequence and use the following steps:
step 1: 25ft-lb
step 2: 50ft-lb
step 3: 85ft-lb except bolt 8 to 75ft-lb only.

I have an '88 FSM and it says to tighten all the bolts in sequence to 110ft-lb except bolt 8 to 100ft-lb. It doesn't mention multiple steps at all and the torque specs are obviously different than the haynes manual:confused:.

Also, the '88 FSM says to use "thread sealant" on bolt 8 and the haynes says to use teflon tape. I'm not sure what specific sealant the FSM means and I'm not going to use teflon tape. I'm leaning towards hi temp RTV.

Any help is appreciated. Thanks experts.

Use the FSM spec, and use PTFE paste (plumbing section) or LocTite PST (industrial/MRO supply, possibly auto) on the threads. I don't like Teflon tape - I often forget which way to wind it.

I've used common plumber's "pipe dope" (PTFE paste) with good effect.

Meanwhile, if you want a quick Tech reference - http://www.kelleyswip.com/tech.html. Working on additions now as well, all specs are from FSM or TSM manuals (therefore factory literature.)
 
I found some Permatex equivalent thread sealant at the parts store that I'll try. Has anyone ever encountered the Fel-pro head gasket that says "use no sealant" on it? I guess I don't need to use any of the head gasket seal spray?
 
The FSM says the headgasket should be installed dry, of course that applies to a standard Mopar gasket.

Install the Fel-Pro dry.
 
I found some Permatex equivalent thread sealant at the parts store that I'll try. Has anyone ever encountered the Fel-pro head gasket that says "use no sealant" on it? I guess I don't need to use any of the head gasket seal spray?

Correct - the head gasket (Fel-Pro or OEM) will have the sealant "printed" on the surface already. That's what those funny blue lines are.
 
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