QuestionI recently purchased this truck. It has a 230hp straight 6 motor that has been rebuilt by the previous owner including a "carb kit". The truck drives and rides beautifully. The problem with it is that after about 15 miles the truck "coughs" - when I was driving it home it back-fired, spewed sparks from the exhaust and eventually stopped altogether. We had to leave it in farmers yard. The next morning when I went to get it, it started up and drove as good as could be, but after about another 15 miles it started all over. It keeps "coughing" (missing?) I finally got it home but that was a long 80 mile trip. If it stops from this it will restart readily and run until the next episode. What is the problem?
AnswerHi Tom:
The problem could be a number of things, but since it only happens
about every 15 minutes, this would lead me to belive it may be caused
by the truck warming up or getting hot. You should check a number of
things to try to pinpoint the exact problem, starting with the fuel line.
1. Could have trash in the fuel line that only gets to the carb after about 15 minutes.
2. You could have spark plug wire arcing once they are warm. Check plug wires or
not old and brittle (look for white dust on wire if arcing) and the cap are on the
plugs tight.
3. Take out one of the plugs and inspect it for carbon build up or oil.
4. Also check the distributor to make sure the points are good. No wear or sticking.
