1985 sunbird should the head be retorqued to prevent gasket failure ?
Never heard of such a thing, but here's my two cents and I'm sure others will tell me how wrong I am, or if my thought on your question isn't bad...
My first thought is "why, does that come loose?"
Other than that, I'm thinking if you're using a torq wrench, what could go wrong? Just be sure to use it evenly across the head--like if you were torquing your lug nuts (100 foot-pounds is the recommendation for our cars), you might do 35 ft-lbs to each lug nut, then 70 to each, then 100 to each (OK, no real need to do that with your lugs, just go straight to 100, but I'm just trying to give an example of what I mean by evenly across the head)
I have a Factory Shop Manual for the 84 Pontiac J-2000 Sunbird
In the manual this procedure is listed is for engine code O and J
The directions it give are:
a. Tighten to 18lbs. ft.
b. Tighten to additional 60 degrees
c Tighten to additional 120 degrees (another 60 degrees on top of the above)
d Tighten to additional 180 dergees ( by now you will have a total of 1/2 turn from the initial 18lbs. ft. torquing)
( I have seen a special tool to measure the degrees of turn at Auto Zone)
1. Start engine and run until thermostat opens
2. Torque all cylinder head/cam carrier bolts an additional 30 - 50 degrees in the proper sequence ...{ I am assuming you already have the proper sequence.}
Paul94Z28 had mentioned to me about discovering something special regarding the head gasket. His is an 84 J-2000 Sunbird Turbo also. He didn't go into detail at the time. Paul did say that he does the hot re-torque procedure on his when he replaces his head gasket.
The Brazil OHC is a finicky piece. Also this is an interference design so be careful when setting up the timing and cam-belt.
I'm not the expert on here, just trying to pass a little on. Paul can definitely fill you in with the better information!! :-)
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Oh BTW if you remove the cam carrier...even loosen the bolts, you have to pull the head too and replace the D@*& ^%&*$ Head Gasket too!! Joy Joy!! :-(
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Photos ain't perfect, but just in case you might like them. I had to try to block out my flash because it was washing everything out.
I just noticed when I looked through the shop manual there is no mention of the need to buy new head bolts , however I am pretty sure the standard practice with the Brazil engine whenever the head gasket is replaced is to only use new head bolts. I would highly recommend this for the Turbo in any case. Hopefully Paul will comment on this.
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Yep - These are stretch bolts, once they are stretched hot - they are done. There are other ways of holding the head and block together if you are interested, but none as cheap as the stretch bolts.
I do as specified in the manual above. I always use 3 Bond. The stuff is GOLD. Do not try and "Check" or in any way muck with the bolts if there is no problem as you will surely create a problem
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thanks for sharing the torque specs, i was just thinking out loud after the car has sat for 10 years, i would rather retorque now than replace a head gasket but sounds like thats not a good idea.
just trying to think ahead thanks for the input
John-
My 84 sat for an 8 year stretch with no mechanical issues, other than the possum moving in that is...
If a gasket is going to go bad it will go bad no matter what you do. Sitting is the worse thing for a car. I would drain the oil and coolant in everything and run some seafoam.
On the inside my car looks like a fighter jet.
When it comes to the head use the old adage:
"If it ain't broke, don't try to fix it"
Definately changing out the fluids is a good idea. Brake fluid too.
Paul - Now there was one Possum that had some Real Class!!
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i sure hope you kept the possum as a pet ( did that come as a stock option )
yes the head bolts do require a retorque after head gasket replacement after you do a heat cycle. They are also torque to yeild if i remember correctly which means you have to replace them every time and cant reuse.
89 355 s10 blazer
94 sunbird, 2.0 turbo 5spd getrag swap
Turbonetics turbo, intercooler, E85 20psi
The possum succumbed to his diet - my wiring harness. We found his corpse and I had never seen one that close before. I thinking to myself "That's funny, I didn't know we had possum in Warren". That was before I found his den under the hood of my Sunbird...
Oh, Paul. I bet that smell had to be very hard to get rid of!! On the other hand Thank Goodness it didn't turn out to have been a Skunk...
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