My brother just picked up a 1984 Chevy shortbed truck with a 305 and 4 barrel carb. The truck is completely stock.
The problem is after idling for 5 minutes or so their is some greyish looking smoke coming out of the tail pipe. When you rev up the engine it goes away after a minute. Also, there is a strong exhaust smell when idling.
What has been done to this point.....
new air filter
new fuel filter
new spark plugs
sprayed a bunch of carb cleaner down the carb while running
put in a bottle of fuel system cleaner
The condition has improved greatly but has not gone away at this point.
All of the vacuum lines appear to be connected except the "thermostatic vacuum switch" which is on the thermostat has one nipple broken off of it and the vaccum line has been plugged with a screw that leads to the distributor. Could that be causing the problem????
Sorry for the long post, this is driving us crazy!!!!
The problem is after idling for 5 minutes or so their is some greyish looking smoke coming out of the tail pipe. When you rev up the engine it goes away after a minute. Also, there is a strong exhaust smell when idling.
What has been done to this point.....
new air filter
new fuel filter
new spark plugs
sprayed a bunch of carb cleaner down the carb while running
put in a bottle of fuel system cleaner
The condition has improved greatly but has not gone away at this point.
All of the vacuum lines appear to be connected except the "thermostatic vacuum switch" which is on the thermostat has one nipple broken off of it and the vaccum line has been plugged with a screw that leads to the distributor. Could that be causing the problem????
Sorry for the long post, this is driving us crazy!!!!