Blown head gasket= bad head???

[GsXtUrBo98]

Well I was thinking about buying a car with a blown head gasket but I was told that with a blown head gasket you would prob have to replace the cylinder head...

When the head gasket fails and the coolent mix's with the oil and flows in that gap I was told that the head would warp because of that... Is that true???

[KNAL_DSM350hp]

Not necessarily. Im sure you could just replace the headgasket and be fine.

[Kevin 1G Drummer]

Unless the headgasket blew because of overheating, you wouldn't need to replace the head. You probably could just get away with resurfacing the head and throw a new head gasket in it. However, if you have the funds and time available, it would be a good idea to get the head decked just to make sure it's nice and flat.

[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.

[brando]

whenever you take off a head it will twist slightly. it may still be within spec but it will twist. again it all kind of depends on how the gasget blew, if it was overheated or if it were just blown from boost. personally i would send any head i take off to a machinist because you never know if it couls have some weird hole or something in it that you cannot see

[GsXtUrBo98]

so no matter what you guys are saying take it to a machinist to make sure everyting is sound with the head...

[95talonracer]

Ya bring it to motors by gosh and he will get it all taken care of.

[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.

[GsXtUrBo98]

how much would you say it would cost to deck the head?

[Capinoy123]

i would say no more than $75. and thats a generous number im throwing out there. what kind of head gasket do you plan on using? because that all becomes a factor to. Gosh is a great guy and knows what hes doing. He will let you know if anything is wrong with ur head.

[GsXtUrBo98]

Originally Posted by Capinoy123

i would say no more than $75. and thats a generous number im throwing out there. what kind of head gasket do you plan on using? because that all becomes a factor to. Gosh is a great guy and knows what hes doing. He will let you know if anything is wrong with ur head.

Well the car that im looking at is a n/a for winter because I wanted to store my GSX so no special head gasket for that

[brando]

yea its not that expensive at all. but deffinattly need to deck the head

[GsXtUrBo98]

Thank you all for your input and ideas

[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.

[CarPsyco84]

isn't the tolerance for flatness on a dsm head .002"? Not that i'm one for sending heads out... I've never done it and have yet to blow a head gasket.