Headbolts


#1

Hi I was wondering what the headbolts need to be torque to on a 1994 chevy cavalier 4 CLY ? The joys of doing a headgasket…


#2

I’d suggest getting a manual. You’ll also need the proper pattern and protocol.


#3

Autozone has a repair guide for your car. Here is the link to the Head removal/installation page.

http://www.autozone.com/az/cds/en_us/0900823d/80/0e/f8/c4/0900823d800ef8c4/repairInfoPages.htm

Ed B.


#4

I believe the head bolts used on this engine are Torque-to-Yeild type head bolts. Which means the old head bolts cannot be reused. But instead must be replaced. This is because Torque-to-Yeild type head bolts stretch when they’re tightened. And once they’ve been tightened, that cannot be reused because they lose they’re clamping force.

If the final torque specs for the head bolts is in degrees instead of in ft-lb’s, you know these are Torque-to-Yeild head bolts.

Tester


#5

I find it funny that the Autozone pages do not make that distinction between standard bolts and Torque-to-Yield. And, do not call for the use of new bolts with TTY. My Haynes manual sure does. Guess the difference in paying for directions, and getting it for free.


#6

You’ve got to scroll down to fig 4. The torque figures, and the turn x degrees (for Torque-To-Yield), are there. You can click on the drawing to get it to enlarge: http://www.autozone.com/az/cds/en_us/0900823d/80/0e/f8/c4/0900823d800ef8c4/repairInfoPages.htm


#7

Please re-read my post. They give you the correct torque and turn to x numbers, but never mention the fact that they are TTY, and never mention the REQUIREMENT for new TTY bolts. That’s my point.


#8

As previous posters strongly suggest and chipping in my 10 cents worth I’d replace those head bolts, they cost $20 - $30 max. You run the risk of either snapping a bolt or not applying correct torque to the head and getting to do it all over again.

I suspect that many of the “I replaced the head gasket and it still overheats” posts on this forum are due to that ommission. New head gasket = new head bolts is not a bad rule to apply.


#9

Hopefully you used a precision straight edge or had an auto machine shop verify if the cylinder head is warped or not. Normally, anything over .002 means it should be resurfaced and .002 ain’t very much.