I have been chasing this problem for 2 years now. Its gotten better with all I have done but I do not trust driving the car.
Problem
first it idles at 1500 to 1700 the three idle screws are backed almost all the way out.
second
when driving down the road 20 to 50 mph NOT under load the engine seems to sputter or miss
when excelerating or under load it drives fine
What I have done
About 2 years ago I had Jeff S rebuild the dist. less then 1000 miles ago
new vacuum adv too. it is working
switched out the wires, points, conditioner, cap rotor, same, so i put Jeffs good stuff back inside, same
switched out the dist, same put Jeff one back
replaced the spark plugs several times
Checked timing a bunch of times, set to 15 BDC did with vaccum plugged
Compression test
cyl 2 was 125, the others were in the 140 range, forgot where i wrote them down
checked valve adj they were ok, loosened a couple a little
Carbs
new filters, before fuel pump and before carbs
fuel pump is a facet pump from Moss. about 5 years old
replaced float needles, gross jets, cleaned fuel bowls, and adjusted, not really dirty
cleaned dash pots and needles look ok to me
checked floats, not leaking
Followed the Book and adjusted the carbs to initial setting, then used a color tune for final adj. Only changed setting some
Sprayed DW40 on card linkage. I think I have some throttle shaft ware. Idle increased some on 2 carbs
The whole problem started with a backfire coming down a hill a couple years ago.
for the last six months the engine backfired a lot but I seem to have gotten rid of that.
I checked the balance tube rubber connections only on tri carb. replaced them. same
I cannot think of what else to do at this point besides getting the throttle shafts fixed and rebuild the carbs.
I was hoping to drive this summer and maybe do that for a winter project.
Any suggestions would be appricated
Thanks Scott
Problem
first it idles at 1500 to 1700 the three idle screws are backed almost all the way out.
second
when driving down the road 20 to 50 mph NOT under load the engine seems to sputter or miss
when excelerating or under load it drives fine
What I have done
About 2 years ago I had Jeff S rebuild the dist. less then 1000 miles ago
new vacuum adv too. it is working
switched out the wires, points, conditioner, cap rotor, same, so i put Jeffs good stuff back inside, same
switched out the dist, same put Jeff one back
replaced the spark plugs several times
Checked timing a bunch of times, set to 15 BDC did with vaccum plugged
Compression test
cyl 2 was 125, the others were in the 140 range, forgot where i wrote them down
checked valve adj they were ok, loosened a couple a little
Carbs
new filters, before fuel pump and before carbs
fuel pump is a facet pump from Moss. about 5 years old
replaced float needles, gross jets, cleaned fuel bowls, and adjusted, not really dirty
cleaned dash pots and needles look ok to me
checked floats, not leaking
Followed the Book and adjusted the carbs to initial setting, then used a color tune for final adj. Only changed setting some
Sprayed DW40 on card linkage. I think I have some throttle shaft ware. Idle increased some on 2 carbs
The whole problem started with a backfire coming down a hill a couple years ago.
for the last six months the engine backfired a lot but I seem to have gotten rid of that.
I checked the balance tube rubber connections only on tri carb. replaced them. same
I cannot think of what else to do at this point besides getting the throttle shafts fixed and rebuild the carbs.
I was hoping to drive this summer and maybe do that for a winter project.
Any suggestions would be appricated
Thanks Scott