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Quick question for all you master mechanics... : ) I do ok and have done a lot I mean a lot of maintenance on my 2002 Ford focus.. Well, last week just had the entire head redone and replaced all gaskets and the head.. And of course wouldn't you know it I had another problem the water recovery tank would not seal (so I bought a new one and replaced it, fixed the problem).. But it was too late.. So yes the vehicle overheated while my 18yr son was driving.. Do you think he pulled over.. Of course not so guess what.. NO WATER!!!! Yep you guessed it... I had to rip the head off again... And have the head redone again... Bottom line is this...
My question is can I use the same head gasket????? because it has literally been on there for a week and the car was driven 1 day (2 hours) with the gasket on.. IT DID get HOT!!!! I mean really hot... And what about the head bolts.. I bought brand new ones a week ago when I did the head the first time.. Will the bolts be ok too????? Your suggestions, comments.... Would be great thank you..
 

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You'll want to mention what engine you have. SPI or ZETEC. SPI head bolts are one time use - TTY Bolts.

Head gasket is less than what $30 now. Never reuse one.
 

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PITA, but that's a good answer from a good source - experienced with SPI as well.

Single use parts, even if never run before disassembly they can't be reused.
 

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NEVER reuse a once crushed head gasket unless it is like solid copper. Even then you could be asking for it. And TTY bolts overheated??? No way..............
 

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You may even need to have the head skin-milled again. Look carefully at the aluminum of the mating surface, if there's any indentations anywhere even the slightest, then have it milled.

I'd put my son on a moped if he did that!
 

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Mine wouldn't get the moped, he'd be walking to teach the money lesson there.
 

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I'm pretty sure as long as a head gasket hasn't been heat cycled it's good to reuse, you can torque it down and reuse it as long as the engine wasn't fired. I could be wrong but I'm pretty sure I remember reading that. Also would get new bolts, as stated the stockers are tty.
 

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Dead wrong there bucko. Anybody you read it from is wrong as well. If the gasket is graphite then simply peeling it up tears it up, no matter anyway, the gasket squishes out of shape to not be evenly thick anymore with the initial torque down. The fire rings on most conventional laminated gaskets are manufactured thicker than gasket base to provide more crush at the critical heat/pressure joint there. Same commonly with water passage rings or for oil. Once the rings are same thickness as the base material from being crushed the gasket is WORTHLESS and may blow in the next five minutes. Same with a single layer steel shim type gasket, the raised crush pattern mashes flat and gasket is then scrap if you yank it. Maybe on a lawn mower but on a car worth enough to spend all that work and money on? Sheer stupidity. Ain't nothing else you can call it.

'...if there's any indentations anywhere even the slightest'

Not sure I agree with that either. If they are flaws yes. If the machine flat is like that no. Some machines intentionally make a cut that is very rough, it will hang your fingernail swiping across it. I would describe those highs/lows as indentations but the cut will grab a gasket like no tomorrow because it has so much tooth to it. Once you crush a gasket on that though it will again be totally worthless as the dowels or pins that index the gasket in no way are accurate enough to rekey the gasket to go back into the exact same grooves made by the head flats. The gasket will be severely marked with them. Ain't no way, not in this world nor the next.

I will not deny that some idiot (me!) somewhere has gotten away with using head gasket over but don't act like it's intelligent, it can and will cost you if you do it enough or in the wrong situation.

PS, I've done it usually on like bike with no coolant passages, car shapes are far bigger and more complicated and much more demanding of the best quality and technique you got there. The bigger size alone implies more runout, you need all the tricks engineered into the new part there to guarantee success. Parts of gasket thicker than others on purpose is a big part of that. Once they are crushed to equal the rest overall you have a half failed part before you even use it. Even the technology involved in TTY bolts requires the gasket to be new to work better with the engine temp swings encountered on all aluminum engines used now. When you reuse a gasket there you have lowered the integrity of the TTY bolt clamp joint.
 

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I was talking the aluminum head, not the block. Last time I did my Zetec both mating surfaces were very smooth. But the aluminum flat of the head was "stained" with a slight bit of corrosion - you couldn't feel anything, but you could see it.

What amc said was spot on - just to add to that, the TTY bolts are essentially giant springs. That is why you turn them past the torque value - it is like squeezing a spring to put preload on it. In operation the head expands and contracts and the tty bolts lengthen and shorten, this keeps the ten thousand pounds of pressure (or whatever it is) on the head flat against the gasket constant. Otherwise what would happen is when the head got hot the gasket would crush more then when the head cooled the gasket would be loose.

Modern head gaskets are an amazing bit of engineering - because not only is the head moving away from the block when it contracts (during the cooling cycle) but the head also slides back and forth against the block a slight amount and the gasket has to maintain that seal. With the multilayer gaskets that sliding is happening in the gasket layers. You can compare and old and new gasket and see this - the 2 layers will not be exactly square with each other.

This is why an overheat kills things - the head expands so much that the tty bolts are stretched too much and the spring is shot.
 
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