I'm new to this website, and I came here looking for some advice/help. I think I'm posting my problem in the most appropriate section, so here goes.

I'll start by saying I'm an experienced diesel tech, so I know my way around a wrench, but I don't have much experience with gassers. My friend has a 1965 Chevy series 60 with the original 327 w/ Rochester 2bbl. Several years back he parked it (running perfect) now I'm working on getting it going again. He cleaned the carb, replaced the fuel pump, had the tank professionally cleaned, and got it started, but it wouldn't rev up above idle. He pulled the distributor cap and said all the springs and weights were froze up, so he got a single wire HEI. I installed the HEI (10ga wired to 30amp fuse in fuse box) along with new plugs and wires. I also pulled the carb and cleaned it til it looked like new. I fired it up and it ran like a top, warmed it up and drove it once around the barn, it sounded and pulled like new. I stopped to do a final check/tune up and realized I had forgotten to hook the vacuum advance hose back up. When I hooked it up the idle dropped from ~900 to ~700, and the engine would not rev up (exactly as before). I have tried everything from feathering the throttle to wide open, choke on/off, even pumping the gas, not 1 rpm difference or even a change in tone or any smoke. I have adjusted the idle mixture screws all the way in and back out, nothing. I have adjusted the timing to both ends of the spectrum (til it runs rough from too much advance or retardation), nothing. I set it back at 10*btdc. Long story short, it has new fuel pump, clean carb, clean fuel, new distributor, plugs, and wires, and it ran great when it was parked, but now with the vacuum advance hose unhooked and open it runs like new, with it hooked up or unhooked and plugged with a screw it won't rev up above a low idle and it's not running rich.

I am at a total loss for ideas, and I'm about ready to tell him to just buy a Cummins and I'll swap it for him haha. Any suggestions or ideas will be appreciated, I know I just must be missing some small detail. Thanks in advance for your help.

 

Trace down the other end of that hose, what is it hooked to? You also will need to put a vacuum guage on it. Need to know how much vacuum at idle it has.

 

The hose comes off the side of the carb. Factory it had a copper line off the side of the carb that connected to the vaccuum advance. I cut the copper line in the middle and ran a vacuum hose from it to the distributor. I'll try to track down a vacuum gauge tomorrow and check it. Thanks

 

Only thing vacuum to the carb base should be the pcv valve. Ported vacuum to the distributor should be from the intake manifold. This may be your problem, the pcv vacuum is constant where as the advance is not.

 

I agree with what you're saying, I've never seen a setup like this, but I know its factory. There is a hose from the front of the manifold that connects to the oil fill tube, it is 10x larger than the vacuum advance, when I started on this the copper lines and fittings were factory made to hook up to the advance. The only other vacuum line on the carb or manifold is off the rear of the manifold to the power brakes.

Should I try teeing the distributor into the vacuum line for the brakes? Any idea why it won't run with the current vacuum advance line plugged?