A good "quick and dirty" test. Definetly indicates more thorough (read
accurate) checking is in order.
The pop-pop is the exhaust attempting to suck air back up the pipe via
the burnt valve, which doesn't seal.
No, I doubt the air pump would inject enough air into the port to have
much if any effect on the POP-POP test
Rick Morrison
72 MGBGT
74 Midget
On Mon, 29 Dec 1997 16:16:29 -0800 Skye Poier <skye@jungle.direct.ca>
writes:
>Hullo,
>
>While looking through the (excellent!) Motorhead catalogue I noticed
>an
>interesting 'dollar bill' test: take a bill and hold it against the
>exhaust
>pipe while running and if its pulled against the pipe 'snap snap' then
>you have incorrect valve timing or a burnt exhaust valve. Seems
>reasonable,
>if the exhaust valve is open when the piston starts down, it would
>draw air
>back up the exhaust pipe. At least, thats my amateur speculation.
>Would the
>air pump not supply enough air?
>
>Is this a reliable method to use? A lot simpler than a blowdown test
>(although I'm inclined to believe not as accurate)
>
>Skye
>
>--
>www.mgb.bc.ca
>
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