I’ve recently had to replace a head gasket on a honda civic, 1500, 3 times. None of the times were due to overheat. The head had been checked and milled true and the block the same. I’ve been advised that the head bolts must ALWAYS be replaced when you R&R the head. My mechanic who supposedly specializes in Honda says he’s never heard of this. True or false.
If these are torque-to-yield type head bolts they cannot be reused. These type of head bolts stretch when the final torque is applied. Which is an angle instead of in ft-lb’s. If these type of head bolts are reused, they cannot provide the proper clamping force to seal the head gasket to the block and head because they just continue to stretch the more they’re tightened.
Tester
Thanks Tester. My local Honda dealer doesn’t carry these bolts … it’s a 83 Civic 1500. Any best ideas for a source for new bolts??
According to this, http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c15280050d28 torque-to yield head bolts aren’t used on this engine. So they shouldn’t require replacement.
However, repeated head gasket failure could be caused from not properly torqing the head bolts. First the head bolt threads must be cleaned along with the threads in the engine block. If this isn’t done it can result in false torque readings. Second, before installing the head bolts, oil must be applied to the threads to perform a wet torque. If this isn’t done, you then perform a dry torque which will result in false torque readings.
Tester
K. Thanks, Tester. I’ll be sure and inform my mechanic to be aware of all this. Seems to me it’s standard proceedure … It’s what I used to do when I was twisting wrenches.
head bolts are now designed to stretch and will no longer be of use once removed from the engine…this is a must do.
When that oil light comes on, it means driving to the good spot to stop is likely to cost you a new engine and it still might not get there, even only three miles. You make your own choice.
With the repeated head gasket problems, should dunchan1 also bring it back after a week to have the head re-torqued?
It’s in every repair manual, but, some people haven’t read the repair manual, to wit: clean the bolt holes of any debris down to the bottom of the holes; use the micrometer to measure the bolt lengths, and compare to the measured depth of the bolts. Measure with micrometer, NOT eyeball!