Hi Mike- I don't have much time this morning... but here goes. Your
engine isn't 'firing' at all (or as you would think). The condition is
called 'dieseling', where your engine is countining to run after electrical
circuits are interrupted (ignition off) by way of compression. The heat
built up and the un-ignited fuel in one or two of the cylinders ignites
under pressure similar to the way a diesel engine works, which subsequently
turns the crank and all other components, then two more cylinders get fuel
pumped in and compressed then they ignite, then the next two, and so on.
There are many things that can cause this dilemma. First things to check:
Bad Gas (usually the major factor)
Bad timing
This scenario occurs similar to the way some explosives ignite. You can
set a match to some things (I wont name them here... I don't want to be
responsible for any fatalities...) and they wont burn to save your soul...
but hit 'em with a hammer... and OH BOY!!! Yee-Haw!!! I'll bet some of
our southern members know just what I mean. Anyway, you're sure to get
many other responses here that should get your truck running fine. Stay
away from those hammers...
Don
'55 2nd DeLuxe
'59 GMC Burb
At 12:38 AM 3/31/00 -0800, you wrote:
>All right,
> My trucks don't exactly fall quite within the category of a "'41-'59
GM or
>Chevy." However, within the next few weeks I will be purchasing a '55-'57
>Suburban or Panel, to be converted it into a "Blazer" so to speak, with a
short
>wheelbase and one piece rear quarter windows (no post). Right now I own a
'61
>step and a '64 fleet, both shortbeds. So, my question is this; I know
you've
>all experienced this one. You take your newly waxed truck out on a nice
clear
>Sunday afternoon drive. You reach your destination and pick a spot to
park in.
>With on-lookers admiring your Oletruck you pull in and twist the key to the
>left. But instead of the tach quickly dropping to zero, the crank almost
stops
>turning, only to change its mind and give a few more kicks! Sometimes it
sits
>there, sounding like a dying animal for up to a minute. It almost sounds
like
>it's turning backwards. In fact, the next time it happens I should jump
out and
>pop the hood to see.
> So, I've been told that if the timing is too far advanced, it can cause
>this. What I don't understand is why there would even be spark with the
>ignition cut off. In which case, the timing shouldn't matter, right? I
do know
>that it only happens when the engine has had time to warm up (at least a
10 min
>drive). And, it seems the warmer it is, the longer it takes to die.
Could the
>cylinders/head be hot enough to ignite the fuel? This is a 235 in the '64
>fleetside by the way. I'll try to adjust the timing when I get a chance,
but,
>if that does fix it, I'd still like to know why.
>
>
>Mike Dempsey
>Pre '67 Fan
>
>
>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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