Surge/bucking after warmed up. Carter 6-1695 1bbl.

[FURY440]

Hi. I have a 66 Valiant /6 225. (New to me) Engine runs great, but after it's completely warmed up it starts to buck/surge while driving down the highway at around 50 give or take. At idle,.it's a little rough also after it's warmed up. It seems to me it's like the ignition is shutting down intermittently or fuel, maybe not? It's has a Carter 6-1695 1bbl. It's been rebuilt.

After checking a few things I have constant vacuum (see picture) at the distributor advance port on the carb and this should be ported. With that said this is most likely the issue as it's always advanced. Is there anyone here that is familiar with the Carter 6-1695 that would know why this port always has vacuum? I know it shouldn't. Possible part missing inside the carb?

Thank you....

 

[Evan Dutch]

Fuel filter, pump. Sounds like you don't have enough fuel volume.

 

[FURY440]

Could be a fuel issue, but like I said after checking a few things I have constant vacuum (see picture) at the distributor advance port on the carb and this should be ported. With that said this is most likely the issue as it's always advanced. Is there anyone here that is familiar with the Carter 6-1695 that would know why this port always has vacuum? I know it shouldn't. Possible part missing inside the carb?

I've heard the Holley 1920 is a pretty good replacement carb. Does anyone know if it's a direct replacement or are there mods that need to be done? But also I've heard that the stock Carters a bit better.

Again, does anyone know why the vacuum advance port would always have vacuum and not ported on my 1695 BBS carb? Anything I should look for?

 

[brian6pac]

Needs more fuel or you have a vacuum leak.