Do LR alloy heads need machining before refitting like cast

[Rovernaut]

Just a thought, if I remove my heads to decarbonise, do they warp like cast or generally can they be refitted without machining?

[mav]

check it out when its off with a straight edge and feeler gauges

[Loanrangie]

whenever you replace head gaskets it would be wise to get the heads machined as it will save a possible blow again and the extra time to strip it down again.

[jessie928]

whenever you replace head gaskets it would be wise to get the heads machined as it will save a possible blow again and the extra time to strip it down again.

errhem, i would have to disagree here... you should NOT EVER machine your heads if you dont have to... You can only machine them a certain amount of times ( depending on how much you shave off), before you have to toss them or start using 2 gaskets ( not good)

It also increases compression which is not always a good thing if you wanto run shit fuel all the time.

SO check it, or getsomeone to check it for you with a straightedge and a feelerguage, if its within the specified tolerance, clean it up and put it straight back on.

Also, check the deck of the block aswell the same way.

JEs

[Rovernaut]

thanks all

[Loanrangie]

whenever you replace head gaskets it would be wise to get the heads machined as it will save a possible blow again and the extra time to strip it down again.

errhem, i would have to disagree here... you should NOT EVER machine your heads if you dont have to... You can only machine them a certain amount of times ( depending on how much you shave off), before you have to toss them or start using 2 gaskets ( not good)

It also increases compression which is not always a good thing if you wanto run shit fuel all the time.

SO check it, or getsomeone to check it for you with a straightedge and a feelerguage, if its within the specified tolerance, clean it up and put it straight back on.

Also, check the deck of the block aswell the same way.

JEs

If he had blown the head gasket i would get them machined otherwise i would almost put a bet on it blowing in same place, as i didnt read his post properly, if it was only to clean the heads up then dont machine if not necessary.

[jessie928]

whenever you replace head gaskets it would be wise to get the heads machined as it will save a possible blow again and the extra time to strip it down again.

errhem, i would have to disagree here... you should NOT EVER machine your heads if you dont have to... You can only machine them a certain amount of times ( depending on how much you shave off), before you have to toss them or start using 2 gaskets ( not good)

It also increases compression which is not always a good thing if you wanto run shit fuel all the time.

SO check it, or getsomeone to check it for you with a straightedge and a feelerguage, if its within the specified tolerance, clean it up and put it straight back on.

Also, check the deck of the block aswell the same way.

JEs

If he had blown the head gasket i would get them machined otherwise i would almost put a bet on it blowing in same place, as i didnt read his post properly, if it was only to clean the heads up then dont machine if not necessary.

Even if the headgasket was blown, there may not be a need to machine the heads, if you measure them correctly, you can be 100% sure if they need a machine or not.

It could be the deck that needs machining, the thread cuold have pulled up through the deck and given thegasket a nudge... if it had helicoils they may let go and pull up also...

IMHO the best practice is always measure, measure and measure again..

Jes