Author Topic: valve lap testing  (Read 1353 times)

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Offline d3buttz

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valve lap testing
« on: February 18, 2009, 05:58:35 PM »
can i test my valve lapping seal with water? or do i have to use carb cleaner/gasoline?

the pic is of the head upside down w/ the water in the valve dome


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Offline MCRider

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Re: valve lap testing
« Reply #1 on: February 18, 2009, 06:02:09 PM »
can i test my valve lapping seal with water? or do i have to use carb cleaner/gasoline?

the pic is of the head upside down w/ the water in the valve dome


Water won't penetrate like kerosene or such. Surface tension and all. I've always done the test the other way, turn it on edge and fill the ports. Look for leaks on the combustion chamber side.
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Offline Jim F

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Re: valve lap testing
« Reply #2 on: February 18, 2009, 06:33:27 PM »
us alcohol, or contact cleaner, its thinner than water.
I did that with my heads after lapping them in but I also
used High spot blue to make sure I had good contact between the sealing surface
and the seat

good luck

Jim
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razor18

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Re: valve lap testing
« Reply #3 on: April 22, 2009, 01:19:41 AM »
the water must be cleaned by the valve dome.it might be that it was in the good factors of testing..



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« Last Edit: April 28, 2009, 09:18:53 AM by razor18 »