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[oletrucks] Low fire on #1 cyl.??? (235 L6)

To: Old Trucks List <oletrucks@autox.team.net>
Subject: [oletrucks] Low fire on #1 cyl.??? (235 L6)
From: J Forbes <jforbes@primenet.com>
Date: Tue, 01 Feb 2000 09:39:41 -0700
The reason it behaves as it does when you pull the plug wire away, is
that the plug is misfiring, the spark is just leaking to ground.  When
you pull the wire away, it makes it harder for the spark to jump, but
when it does jump, it hits the plug with full voltage, and fires it
instead of just leaking to ground.

That plug is probably fouled...you might try a new plug, but the new one
may foul again quickly if you have other engine problems.  If a new plug
solves all your problems, I'll send you a bill for consulting services  
:)    (not really)

A compression tester is a gizmo that goes in the spark plug hole, and
measures the air pressure build up as you crank over the engine.  It
should come with instructions.  You are looking for a variation among
cylinders...they should all be within about 15% of eachother.  So, if
you find 50 psi on #1, and from 110-125 psi on #2 thru #6, then you have
found the problem is with compression in #1 cylinder.

A dwell tester is an electronic meter that measures how long the points
are closed...in degrees.  They used to be widely available, but since
most carmakers quit using points about 25 years ago, you might want to
look for one at the swap meet.  But, you might find a new digital
tune-up meter that has a dwell meter and tach built in, as well as a
voltmeter, for a reasonable price.  I haven't shopped for one lately.  

You will want to set the points at .015" gap, or 38-45 degrees dwell, if
it is indeed a 1953 vintage car distributor.  If it's a different year
distributor, the points should have a different adjustment.

Good luck...

Jim


----------------------------------------------
VIKINGHILL@aol.com wrote:

Could someone please tell me the correct gappage for the points and
plugs on 
my 1953 235 ci. (the one with hydrolic lifters)?
I currently have the plugs at .040if an inch, and the points at .018". 
I am 
getting no noticeable fire on the #1 cylinder. If I pull the plug wire
almost 
all the way off, the plug suddenly comes to life and the engine smooths
out.  
The #1 cylinder is getting some major smoke as well.  I cleaned the Plug
in 
question and re gapped and to no avail, I still get a slight
skip...unless 
the arc is jumping the area between the plug and wire???  I appreciate
it.  
It looks like the 6 cyl is slowly dieing.  (Any one know of a good,
resonable 
rebuilder in the N.W. Ga. / Chattanooga Tn. area?
Thanks,
Casey
'47.5 sputtering it's way down the road..... 
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959

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