palomarhs4x4

some one mentioned to retorque my head bolts while the engine is warm on my 22R I though tthis was wrong, any ideas bout this and if wrong what can come of it?

rowdy235

torqued mine on my 82 totally cold and haven't had a single problem in about 10,000 miles. Just do the torque in three steps (20 40 and 58 If I remember correctly), and you should have no problems.

Not sure about a retorque but I'm pretty sure its not recommended to use the head bolts more than once (I did anyway), so I doubt a retorque would be wise. If you are having a headgasket or similar issue, the only real option is to pull the head and redo it.

cdg

Now this comes from general automotive experience...

In the case of our old Toyotas, they are of iron block and iron head design. As a general rule iron castings tend to be much less heat sensitive than aluminum ones do. Be careful with this fact though because all castings expand and contract with heat. My point here would roughly be that while you should be careful with all engine castings, some are inherently more sensitive than others...

In most cases head torque is done just as specified above with the engine cold. Usually there are "steps" that you climb as you follow a specified cross-tightening sequence that is found in most shop manuals. 3 torques is a fairly well practiced standard across the board.

However some reading does suggest that some engines are best served with a 4th torque check after warming up the engine. Assuming that you have an accurate torque wrench, this should never in any way damage your engine to simply verify the torque with the engine warmed up.

I say this also having recently come from working on a Renault turbo diesel. They are fragile creatures of all aluminum (iron sleve) construction. They specifically require a warm torquing and in fact can be proned to head gasket failure when the 4th torque is not applied.


That having been said I don't believe this is necessary on all engines. So in conclusion, use your best judgement. I can't see it doing a ton of harm or good either way...


Now as for what I have done on every head gasket I have done... I will follow a 3 torque step (if one is not specified I will make one up that makes sense). After reaching the correct specification I will warm the engine up to operating temperature, then allow it to cool down at least most of the way. Then give them one last check before tightening down the valvecover. In my mind this gives everything a chance to expand and re-contract once - giving your head bolts a chance to stretch and your gasket a chance to compress a little.


I could be full of crap though. That's just how I was taught and how I do it.

palomarhs4x4

Thanks everybody for the info I originally torqued them in about 10 steps crept all the way to 60lbs thought i should be as safe as possible with aluminum head and the new gasket then in moment of pure memory loss retorqued them when warm. the engine runs great but worried i might have shortened the life of both my head and H/Gasket.