Re: Overfiring?

[jlandry@domain.elided (John A. Landry)]

On Tue, 25 Nov 1997 18:04:53 -0500, J MICHAEL SHAW II
<103253.3336@domain.elided> wrote:

>This one I bought about six months ago ugly as sin, but running fine-except
>for the 40-60 accelerator pumps it took to get the thing to start in the
>morning.

Did the rebuilt carb solve this problem?

> It is fine for ten or twenty minutes, then starts coughing and bucking. 
>If I pull over it stops, but will start again within about five minutes of
>starting up.  It sounds like an extra, mis-timed combustion is taking place

Hmmm... sounds like maybe a heat related problem.  The offending device
heats up and malfunctions, you pull over, it cools off a bit and behaves
for a time until it heats up again.

>I've tuned it up and set the timing and still no
>change.  There seems to be no play in the distributor shaft, and my
>experience with dist. problems always left me cutting out, not
>over-igniting.

Did you replace or clean (as appropriate) the points, condenser, plugs,
rotor, distributor cap and plug wires?

What about the coil?  Have your tested and or replaced it?  I'm thinking
maybe the coil's getting hot and malfunctioning???  It does happen.

>I'm now guessing it must be something in the valves
>sticking once the engine is warm.  However, there's only 111,000 miles on
>it, and my T-all and Father's Scout had many more miles without ever having
>any problems.  I'm usually pretty good diagnostically figuring things out
>with the peripheral additions to the engine, but have never gone into the
>meat of the engine itself.  Any advice?  Valves, or should I try a new
>distributor first?

I wouldn't suspect the distributor as being very high on the list of
culprits.  Seems like if it was causing a problem it would more or less
happen all of the time.  Valves... maybe, but I really don't think so
either.  You should do a compression check before you spend any money on
something like a rebuilt distributor.

Good luck,

John
------------------------------------------------------------------------
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