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Author Topic: Do I need a new head?  (Read 989 times)

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Offline Johnny5

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Do I need a new head?
« on: July 15, 2009, 07:57:01 PM »
Im in the process of rebuilding a 750K3 and got the top end of the engine apart. Found the reason for the head gasket leak - a nice set of gouges from something sharp to pry the head from the jugs. Thanks PO. It looks bad, Im guessing about a mm deep and runs as far as where the valve "cup"? begins. Is this too much to have a machine shop shave off? Im thinking yes, but wanted to get some opinions first before I begin searching for a new head.

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Offline MRieck

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Re: Do I need a new head?
« Reply #1 on: July 15, 2009, 08:02:19 PM »
1mm is to deep to mill off as you will get way into the valve seats and the compression will be up there. Valve to piston clearance is also an issue. You could have the worse gouges tig welded and then have it milled a bit
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Offline Sam Green Racing

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Re: Do I need a new head?
« Reply #2 on: July 15, 2009, 08:03:03 PM »
Can you post pictures of the damage ?

Sam. ;)
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Offline Johnny5

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Re: Do I need a new head?
« Reply #3 on: July 15, 2009, 08:04:23 PM »
Quote from: MRieck on July 15, 2009, 08:02:19 PM
1mm is to deep to mill off as you will get way into the valve seats and the compression will be up there. Valve to piston clearance is also an issue. You could have the worse gouges tig welded and then have it milled a bit

That's what I was afraid of. I suppose I could find a head on ebay for about the cost of getting the work done to this head.

Thanks for the info.
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Offline BlackMax

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Re: Do I need a new head?
« Reply #4 on: July 15, 2009, 08:39:33 PM »
Call APE to find out what's possible. 

How much decking can you compensate for by cutting new deeper valve seats?  I decked my head due to a gouge, and compensated with the new seats. 

APE   661-256-7309
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