what is the proper pounds of torque to put on the head bolts of a 1986 pontiac sunbird 1.8L station wagon?
At first this may sound like a dumb question, but according to the motors manual and the parts store we dont get an answer in pounds of torque on a torque wrench… but in degrees to turn the bolts (ie: turn 18 complete turns then turn them all 60 degrees then 40 and so on) . The heads have warped and i’m getting them shaved in the next couple days, so i’m afraid those directions will no longer be accurate due to the diffrence in size of the head.
I have no clue to a factual answer for you, but based on what you’ve described you may want to take a close look at the bolts and the holes. The bolts may bottom out before you can snug the heads down. I’m guessing that if the number of turns has been indicated that the bolts bottom out to prevent overtightening, rather than depending on a torque wrench. If this is true then you would have to shave the bolts by the same amount. Of course the real problem becomes measuring the amount taken off at the various bolt locations (since it was warped different amounts of material will be taken off across the face.).
Is there a torque recommendation for the head gasket?
Or…tighten until the bolt breaks and back off a 1/4 turn.
I’m sorry I don’t have a manual that covers that engine. I would suggest to carefully review the torque specs, maybe find another manual to refer to. In 30 years of auto repair, I’ve never heard of instructions to tighten bolts a given number of turns. A typical spec for torque-to-yield bolts* is to tighten them a given number of foot-pounds, then an additional X degrees, and sometimes then another Y degrees. Maybe it’s an oddball thing I just happen to have not run into yet, but I find this “18 full turns” thing highly suspect, and wonder if it’s a misprint or is being misread.
*This type of bolt is never to be re-used once tightened. Use only new bolts.
OK, according to the service manager at the Pontiac dealership here in town.
(disclaimer: I now hate Pontiac for making this so difficult. When I had my '69 Goat I could fix anything in my sleep)
Torque the bolts to 18 ft/lbs. Then go another 60 degrees 3 times. (60 degrees, another 60, another 60)
He said there’s a tool you can use to make it easier which your Pontiac dealer should have. It sounded like DeWalt, but that wasn’t it, so ask if they have something that sounds like that.
I had hoped to help you out more, but that’s the best I can offer.
Okay, what duffer posted makes sense. Somebody somewhere misread “18 ft-lbs.” for “18 full turns.” (By the way, on thinking a bit more, two things struck me: it would be difficult or impossible to establish a starting point for full turns, and no head bolt would turn nearly that many times anyway.)
The tool referred to is an angle gauge that can be attached to the socket to eliminate guesswork in determining how many degrees one has turned the bolt. Your parts store might offer it in their tool selection. An alternative is to cut out a 60 degree wedge from an index card (made with a protractor), lay it carefully next to the bolt with one edge aligned with the wrench handle, and turn until the handle aligns with the other edge.
I just make a mark on a corner of the hex head and the surface adjoining it. The corners are 60° apart. When the next corner is pointing at the mark, you’ve turned 60°. If you’re distracted or called away, you can instantly tell at a glance the state of each bolt, i.e which have been turned 60° once, which twice, etc.
It’s also more accurate than a wedge for multiturn procedures. If you habitually (due to your viewing position or whatever) turn a few degrees too much or too little, the wedge method adds the errors for each turn. With the “marked corner” method, final position after the third turn is as accurate as the first, because you’re reading its true position (60°, 120°, 180°) not adding three measurements
You can also do this with 30° turns (by turning from corner to the middle of the flat side, or vice versa). For 90°, scratch a line connecting a pair of opposite corners, and the midpoints of two opposing sides to form a perfectly centered perpendicular X.
