Hi Paul
If you can get an old spark plug and assuming you can get the car near a
high pressure air line, take the spark plug innards out, this is done by
crushing the ceramic, then have an airline connection or a piece of tube
welded on so you can connect it to the high pressure air line. Turn the
engine until it is on the firing stoke for the cylinder you wish to test and
then engage 1st gear with the hand brake set, this will hopefully prevent
the engine turning far enough to open the valve. Once you have done this fit
the modified plug and pressurise the cylinder, then listen to the end of the
exhaust pipe (make sure the engine didn't turn so as to open a valve on the
cylinder you are testing) if the valve isn't seating you will hear a hiss
from the exhaust, if it is the inlet you will get the hiss at the air box,
this gadget will also test for blowby of the piston rings, listen into the
rocker box, and find leaks in the head gasket between cylinders, to do this
you must first be certain that your valves are working properly, then if you
pressurise one cylinder and get air out or either inlet or exhaust it must
be passing into an adjacent cylinder and passing out through the open valves
or if you have all the plugs out you will hear it in the plug hole.
I hope my description isn't too confusing, I just no someone out there has
the abridged version.
Graham.
2.5 PI MKII
Sprinted Dolomite
2000 MKI
Toledo
1300 Front Wheel Drive
http://www.triumph-iw.co.uk
> 1.) How does one diagnose a burnt exhaust valve without taking the head
off.
> This guys mechanic didn't, so I wondering if this is the source of the
> problem.
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