1959 235 6 cyl. tune up issues......

[john dob]

hi - i have a 1959 chevy apachie 3100 with a stock 235 6 cylinder and 3 speed on the column. the truck runs great up to 45-50 mph then it sputters like it is running out of gas. i have done the following to the truck: new gas tank, new fuel pump, new fuel filter, re-built carb (rochester type B), new plugs, new wires, new points, new condenser, new dist. cap, new rotar. the dwell reads right within in specs (approx. 30). i can only set the timing by ear and feel. i have looked a few times and can not find the timing ball mark on the flywheel. i even took out the plugs and rotated the motor by hand a few revolutions and still can't find the mark. i advanced the timing until it kicked back on the starter and backed it off a bit. starts, idles smooth and runs great until i wind out second gear and try to accelerate 3 rd. gear past 45-50 mph. i thought about changing the float setting but it is right where the instructions said it should be. i am thinking the timing is either still off or i have some carb. issues. hate to spend the $300 on a carb. and still have it act up. any thoughts would be greatly appriciated. thanks - john (wilmington, delaware)

[Jurassic-1]

What about the Vacuum advance? is it working. Are you setting the carb with a vacuum gauge?

[john dob]

thanks for the reply...........the vaccum advance seems to be working (the dist. rotates when you accelerate). i need to put my vaccum gage on the advance and make sure it is holding a vaccum. i did try to set the carb with my vaccum gage but was getting a erratic reading and gave up on it. needle was bouncing around and not steady. is the erratic vaccum reading telling me something ??

[OrrieG]

Here is a link to reading a vacuum gauge.

https://www.google.com/search?q=read...1Q5gDu#imgrc=_

Sounds like your "new" fuel pump may not be up to the task?? Have you ran a compression test on it? Bouncing vacuum can indicate valve issues that might show up with compression test.

[john dob]

thanks for the tips. i did make some headway. i found the timing "ball" (had to use my harbor frieght inspection camera and painted the ball white). i set the timing and dwell. still cuts out at higher RPM's. i sprayed carb cleaner all around the carb, intake, exhaust and lines......no signs of any vaccuum leaks. i sprayed the carb. cleaner right down the carb and pushed the throttle.....still cutting out so i am thinking i have eliminated fuel issues. i read online that a bad coil can cause missing at high RPM's so i just bought a new coil to try tonight.

[OrrieG]

In the good old days (early 70's) I worked in a service station in Phoenix. In the summer we saw a lot of Fords with stock coils that would get too hot and do what you described. Installing an aftermarket one fixed the problem. Also, timing by ear is not a bad thing. Timing light will get you close but bumping it either way, usually a little advance, will get you to optimum. I usually advance it until it runs really good at idle, then retard it a bit. Test drive, repeat until happy.

[john dob]

update...........the new coil did not make any difference. i did some more reading online and saw some old posts about the spring return on the points not being strong enough to close the points all the way at high RPM's. the new points i put in are the style with a bent metal strap that is the return spring. i remember thinking when i was setting the point gap that it did not take any pressure at all to open the points up. u could see them not closing all the way at high RPM's but not sure how to improve this. any thoughts on this ???

[john dob]

problem solved !! finally............i bought a second set of points and immediately saw that there was a second spring clip that was not included in the first set. the first set was only working off of what ever spring tension i was getting out of the copper strap. put the new points (and spring clip) in and the truck runs like new.

[OrrieG]

Yea!