Technical Carter WA-1 1bbl issues? Maybe? Help please lol

Hey everyone!

I'm running into an issue with my 1950 Pontiac Streamliner with the inline 6. I'll try to lay everything out and hopefully we can get to the bottom of it.

I replaced the original Carter WA-1 with a rebuilt one off of eBay with internals supposedly more suitable to ethanol gas. I was chasing what seemed like a loud whistling vacuum leak once hot. At the same time I did some other replacement parts as well including coil, wires, plugs, fuel pump, inline filter, fuel pressure gauge, vacuum advance line (troubleshooting this issue).

The car idles like a dream. Got the idle and mixture screws dialed in and it will sit and run at idle indefinitely without overheating or vapor locking. I previously had a vapor lock issue, but ended up installing a fuel filter with a 5/16" inlet from pump, 5/16" outlet to carb and 1/4" return. The car didn't have a return line originally, so I ran one back to the tank and it completely resolved the vapor locking when driving in traffic or hot weather. When you give it a little throttle, imagine trying to hold a 2k RPM for example, it starts bogging, sputtering, missing, etc. like crazy. Let off the throttle and it goes back to a nice idle. Snap the throttle wide open and it revs up smoothly and returns to idle smoothly. It's only when you are giving it partial throttle is when this becomes an issue. This happens when stationary (parked) or when driving. One thing I noticed while troubleshooting is it appears the heat riser flap in the exhaust appears to be frozen in place. I can't say how long it has been that way, only that I noticed it while going through everything. Car ran great with the old carb, I was just at a loss trying to figure out the vacuum leak so I opted to get a rebuilt one. I also removed the wiper motor vacuum line from the side of the intake manifold and plugged it to eliminate it from the situation.

Should I disconnect and plug the vacuum advance line at the carb to see if anything changes? The dizzy is original, the points appear to have been replaced "recently", as I've only owned the car for about 9 months or so. Here is what I have done in the time I have owned the car for a broader picture: 6 volt alternator, "new" carb, wires, coil, plugs, rotor, all fluids. Everything else is cosmetic like new leather interior, gauges, carpet, etc. Looking for some input on where to start. I've had the "new" carb installed for about a month and have driven it maybe 10 times, mostly locally, with this issue which has gotten worse.

Thanks in advance!
Chris

 

I would check to see if the vacuum advance will hold a vacuum. If it won't that could make the carb lean at part throttle. I'd also clamp off the return line to the fuel tank and see if that makes any difference in the part throttle bog.

I'd say you are lean at part throttle. Try placing your hand over the top of the carb when it is bogging and see if cutting off some of the air going through the carb makes it perk up. That would prove that your problem is carburetor related. Hope you saved the old carb so you can rebuild it if necessary. Also, you really need to get the heat rizer repaired.

 

I'll give those a try tonight.

 

Liquid (this time fuel) as with air is going to follow the path of least resistance and it may be that there is too much fuel being allowed to go back to the tank at part throttle when the engine wants a lot more gas than at that perfect idle or loafing along at a comfortable cruising speed.

Try this before doing anything else. If it is driving take it down the street and where you have space nail it and when it starts to die out let off the gas just like you would when you shift gears for about that length of time and hit it again and see if it picks up and pulls until that same thing happens again. Then you know it is fuel delivery to the carb that is the issue.
Back in about 1974 I decided that I wanted a 55/57 Big window Chevy truck and sold my 48 and ended up with a 57 panel with a serious 327 in it with an Engle cam, 12.5 Jahns pistons, 2.02 heads and a 2 -4 early Corvette intake. That truck would pull the front wheels and pull like crazy until just before it was time to shift and then run out of gas, Let off the gas and shift and it would pull like crazy again until it was time to shift to third and it would fall on it's face. It idled good, ran down the freeway at way faster than the posted 55 mph great but fell flat on hard acceleration. One day I decided to get to the root of things and took the fuel lines to the carbs apart and found that someone had put in a natural gas fitting in the fuel line that had about a 1/8 inch orifice if that rather than a full diameter orifice. A run to the parts house for a fitting and no more stall out. Funny thing is that a few months later I traded it straight across back for my 48 but from a different guy than the one I sold it to.

 

Talk about an amazing story!!! Love that you got it back! I’ll be looking at the suggestions in the morning. Had to take my daughter to Girl Scouts tonight.

 

Got it figured out. The dual points were way off. Got them adjusted correctly and it’s good to go. Thanks guys!