Question about 1994 Jaguar XJ12

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Damage heads due to overheating.

I have try to take damage heads out but heads are in there good.
To replace the heads do I need to take engine out?.
Thank You

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No the heads seize to head studs need lots of antiseize or crc product arround head studs head will require lots of levering to slowly remove good luck very hard to remove

Posted on Apr 20, 2009


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Posted on Jan 02, 2017

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SOURCE: Heads damage. due to overheating.

I have never worked on a 79 Jag, but I have worked on a lot of engines. The advice I would give you is what I would do, and what I would do would be to take the engine out and work on it rather than leave it in the car. Especially a V 12. I know that it is a lot of work removing the engine, but to pull the heads you have to do almost everything needed to remove the engine and then you are not working over the fender of the vehicle where at times is a pretty hard feat in itself, plus you have to worry about the car's finish also. Good luck my friend, you are in for a big job, but I know when you get it done you will feel REALLY good about it.
BTW, what ever you decide, before you start take alot, and I mean alot of pictures that you can put on your computer and blow up. It will be invaluable to you when you are putting the thing back together. It will help you route cables, gas lines, vacuum lines, etc. Take pic's every step of the way. When you remove the radiator take pictures, this will help you see things you can't see when the radiator is in, air filter, battery etc. I can't enphisize it enough.
I hope this helps you in some way.

Posted on Apr 19, 2009

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