repair cylinderhead

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bavarian_knuckle
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repair cylinderhead

#1

Post by bavarian_knuckle »

Hi guys,

have a real nice extra set of 39 small port heads and struggle with keeping or selling.
Front has a hairline crack where the pipe goes in .. doesn't go all through to the valve seat.

Now, is this an "easy" fix or should I leave it and let them go ...

Guess what I want to ask is if these heads a weldable?

thanks
Klaus
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Buddhahoodvatoloco
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Re: repair cylinderhead

#2

Post by Buddhahoodvatoloco »

I would say so, bake the shit out of them first.
bavarian_knuckle wrote:
Mon Dec 02, 2019 6:22 pm
Hi guys,

have a real nice extra set of 39 small port heads and struggle with keeping or selling.
Front has a hairline crack where the pipe goes in .. doesn't go all through to the valve seat.

Now, is this an "easy" fix or should I leave it and let them go ...

Guess what I want to ask is if these heads a weldable?

thanks
Klaus

47str8leg
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Re: repair cylinderhead

#3

Post by 47str8leg »

I'm not a welder but have seen this done. A kiln seems to be the best way to acheive this. Slowly bring up to required temperature , weld with appropriate rod then slowly reverse the temperature . Keeps the area around the weld from becoming brittle.
The amount of temperature over time is unknown to me. Just my basic understanding of the metallurgy involved.

Andygears
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Re: repair cylinderhead

#4

Post by Andygears »

47str8leg wrote:
Mon Dec 09, 2019 5:03 pm
I'm not a welder but have seen this done. A kiln seems to be the best way to acheive this. Slowly bring up to required temperature , weld with appropriate rod then slowly reverse the temperature . Keeps the area around the weld from becoming brittle.
The amount of temperature over time is unknown to me. Just my basic understanding of the metallurgy involved.
Agreed, and while on this thread, does someone know the exact metallurgy of knucklehead heads? And type of rod/process that works well? Sharing now could keep original heads from being ruined. A knowledge base item?

Andygears

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