Is it common to re-torq head??

[BBRacer]

Did a head gasket on my '65 6 cyl two weekends ago and though a pain in the #$@# it was successfull. Compression came back, all leaks gone, sounded better, more power....

Now it leaking again, and it feels as if power is down. Can you re-torq the head again? Does this affect the gasket or is the gasket screwed and I need a new one??

I feel as if it just needs everything re-torq'd again - I will try that anyway before I put another new gasket in but is this common when you replace a head gasket??

 

[mustangdave]

No, you shouldn't have to. Is it possible you put the gasket on backwards? They should have been marked "front" on each gasket; this side would go toward the front of the engine and up. It's also important to use the right sequence when toquing the heads and a torque wrench is a must. There is one other possibility; when the gasket blew the first time, it could have warped the deck of the block or the heads. In that scenario, they would have to be milled to get them perfectly flat again.

 

[Max Power]

I have always been tought to re-torque it after a heat cycle. Give it a try, it's cheaper than any alternative and doesn't cost anything.

 

[ForceFed70]

Most automotive manuals say you should re-torque it shortly after the initial install. Tho if it's leaking, I have a fealing it's too late.

 

[Route666]

I also have been taught that heads should be re-torqued every time they are put back on, after a run, or a heat cycle in Mr. Power's words.

 

[Max Power]

I always do the cam break in by running at 2000 rpm for 20 minutes, shut it down, change the oil, re-adjust the valves and re-torque the heads when breaking in a new motor or doing a cam/head install. I have never had one leak.

 

[2nd Mustang]

I personally never had to retorque head after installation, maybe just really lucky. Another remote possibility is that the head bolts have stretched with age and cannot hold the torque value.

 

[rbohm]

whether you need to retorque the head after a heat cycle or not depends on the head gasket. some are of a perma-torque design and need no retorquing, others do need retorquing. for those that always retorque after a heat cycle, dont build a 4.6 ford engine because the head bolts will break as they are a torque to yield design and can only be torqued once.

 

[BBRacer]

Thanks all. I printed this and now about to set out on the journey. I'll re-torque this weekedn and then let you know. My gut feeling is that I will be doing that head over again.

I should have asked before I did the job... but which gaskets are the best to use??