The first thing is to be sure it's vapor lock (or a fuel problem). If
you don't have a see through filter get one! A plastic one will do for
now, mount it right at the carburator. You don't have to cut the fuel
line, you can slide rubber line over the flare on the end and use a
flare nipple on the carb to attatch the rubber line to.
Make a note of the normal gas level in the filter then next time it does
it, check to see if the filter is much emptier. If it is you have a fuel
delivery problem maybe vapor lock. If the fuel level is normal, take off
the air cleaner, look into the carb (engine off!!), pump the accelerator
and see if gas squirts into the carb. If not you have a carb problem
(unlikely but possible).
If you are getting gas through the carb, check spark next. A bad coil
can do this. Have your wife hold a spark plug wire in her mouth as you
crank the engine, oh, no, sorry forget that part,(those are the discount
divorce instructions). Anyway check to see if you ae getting spark by
pulling the coil wire from the distibutor and holding it about 1/4" away
from the engine (with insulated pliers!). Have the wife crank it over
and see if spark jumps. If not you have an ignition problem, probably
'49 Chevy Panel http://www.strato.net/~jrdorsey/truck.htm
'52 GMC Firetruck http://www.strato.net/~jrdorsey/fire/fire.htm
'51 Chevy suburban http://www.strato.net/~jrdorsey/burb/
Brad Newman wrote:
> Yesterday afternoon I experienced what I assume was vapor lock.
> The wife and I drove approximately 25 miles on the freeway (60-65 mph),
> and as soon as we got off on the side streets and slowed down the engine
> quit. After it sat for a couple of minutes it fired back up, then would
> die again after a couple of minutes. We finally got to where we were
> going, it sat a couple of hours, and we were able to drive home with no
> problem. This morning after driving approximately 5 miles it did it
> The temps yesterday afternoon were in the mid to upper 90's, with the
> humidity being somewhere in the 65-70% range. Last night on the return
> trip the temps were in the low 80's, as they were this morning when it
> happened again. I'm running a stock 216, and the truck has just recently
> been completely (frame off) restored. The fuel tank was vatted and
> sealed, I have 2 inline filters, and the fuel lines are run where they
> were originally.
> What do ya'll think; does this sound like vapor lock, and if so, is
> there a sure fire way to prevent it from happening again? My neighbor
> tells me that when it gets hot (a constant here in Texas), that vapor
> lock pretty much becomes a common occurrence on these old trucks when
> speed is mixed with heat and humidity. Does that sound right?
> Thanks for any help.
> Brad Newman
> 49 3100 Deluxe
> 24 1 ton
> Coppell, Texas
> 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