Blown head gasket= bad head???

[brando]

every time you take off a head it will warp. ask any machinest and they will tell you this. when you take it off you will need to mill it down. now that isn't hard and its pretty cheap but they will probably find some bent valves also

[EclipseGST]

Originally Posted by brando

every time you take off a head it will warp. ask any machinest and they will tell you this. when you take it off you will need to mill it down. now that isn't hard and its pretty cheap but they will probably find some bent valves also

I dont know who you heard this from or what machinists you've been talking to, but I have replaced many head gaskets on a lot of vehicles with the heads perfectly fine. Especially on DSM's. I always check the surface of both the block and head, but rarely is the head warped.

[AwdGSX13]

bent valves from a blown headgasket? You would have to let it go to the extreme for that lol...Deck the head and call it a day.

[JET]

Originally Posted by brando

every time you take off a head it will warp. ask any machinest and they will tell you this. when you take it off you will need to mill it down. now that isn't hard and its pretty cheap but they will probably find some bent valves also

That is not correct. Warping is caused by heat Yes, no head is perfectly flat, so it will twist some when put on (less than a human hair though, which is .003" - .004" BTW).

If you know the head was flat before and it was not overheated, then there is not point in taking it to a machinist unless you are having repeated problems. If you are blowing head gaskets because of poor tuning or too much boost, it will not normally warp the head.

In this instance I would get the head checked because you do not know the history of it. I just don't want people thinking that you need the head checked every time you change a head gasket and wasting their money.

[GsXtUrBo98]

Originally Posted by JET

That is not correct. Warping is caused by heat Yes, no head is perfectly flat, so it will twist some when put on (less than a human hair though, which is .003" - .004" BTW).

If you know the head was flat before and it was not overheated, then there is not point in taking it to a machinist unless you are having repeated problems. If you are blowing head gaskets because of poor tuning or too much boost, it will not normally warp the head.

In this instance I would get the head checked because you do not know the history of it. I just don't want people thinking that you need the head checked every time you change a head gasket and wasting their money.

Well put... and very informed.