Bogging update

[Doug&Deb]

Still no resolution to my problem. Points are good and gap is correct as confirmed by my dwell meter. Timing is correct as is idle speed. I isolated the ignition switch to see if it was bad and it’s not the issue. Fuel filter is clean and sediment bowl also. I’m running out of ideas. Possibly the condenser but the engine idles smoothly so I’m not sure. I’ll try to add a video for the sound.

[desoto1939]

did you take or rebuild the carb recently?  Check the step up piston. did you soak the leather in light oil to soften the leather. Is there any crap in the sediment bowls on the fuel pump and extra gas filter?

Is anything sticking on the automatic choke or other linkage.

 

Do you have the correct base gasket the one with the four slots?

 

Rich Hartung

desoto1939@aol.com

[Doug&Deb]

No carb problems that I can tell Rich. The rebuild was around 1000 or so miles ago. Nothing in the sediment bowl or in-line filter. Fuel that drained out of the line was clear. The car idles smoothly. When I give any throttle it chugs and shakes. I tried to add a video but it’s too large and I don’t know how to condense it.

[LazyK]

check your vacuum advance. diaphragm cracked or linkage stuck? 

[desoto1939]

are all the screws and bolts tight on the carb. Sounds as if you might have an air leak or vaccum leak. How old is the rubber hose that feeds the fuel pump? If it is an older hose and not ethanol fuel usgae it might be getting clogged. but has enough of an opening to let the car idle but when under a load it is colapsing internally.  Just a suggestion. Could go to NAPA and get modern hose clamps and the correct size opening and cut a temporary fuel line to see if that solves the issue then get the correct hose.

 

Rich

[Doug&Deb]

Ethanol resistant hose. Everything tight on the carb. I’m going to replace the inline fuel filter just because they’re inexpensive. No vacuum leaks that I can find. I just finished rebuilding the correct distributor for the car. The one that came with it works but it’s for a 49/50 Coronet. While I’m into changing it I’ll do a compression test. This has me stumped ( not that it’s hard to do). 

[P15-D24]

Been my experience a bog off idle is running too rich. Try running without the air cleaner for a test.

For another test try plugging the distributor and carb vacuum ports to rule out a vacuum leak. 

[47 dodge 1.5 ton]

Does it improve without distributor advanced hooked up and plugged on carb? Sounds like it could be advancing too much from idle?

[Doug&Deb]

I’m thinking it’s a problem with the vacuum advance. As soon as I have time I’m going to check. I’m going to change the distributor anyway but I’d like to solve the problem for my curiosity. 

[Plymouthy Adams]

vacuum advance could cause the internal shorting...HOWEVER on acceleration the loss of vacuum puts this out of play.....only when at cruise and low load will the vacuum signal cause for full advance of the points.  Just plug the vacuum line for a quick check though.  You could be drawing your vacuum non ported...if so, this is wrongly set up but again with acceleration you will lose the vacuum and all things go mechanical while under load and acceleration....but if non ported...you are pulling vacuum advance at idle...not sure if you are disturbing the little wire or not.

Edited December 22, 2021 by Plymouthy Adams

[Doug&Deb]

Which wire are you referring to? Something in the distributor? I’m going to try plugging the vacuum line next. This was a sudden problem. Prior to this it was running great. It’s probably something simple. With my limited mechanical skills it becomes a slower learning process. With 6 grandkids and Christmas 3 days away free time is limited lol. 

[Plymouthy Adams]

while may not be the problem....I will repeat....look at the condenser....they run like new idling, revving and not loaded...put it under load, falls on its face.....usually you can start seeing the bluing of the point contacts as an indicator but not always a guaranteed tell sign.   If you have one to swap only takes a minute and no change to the points setting....if you have a capacitor meter to read this...will/should be .18 -.25mfd (avg) cannot get the spec from the book...this would be just a quick check as you would still need do breakdown test...resistance test.....swap with one is usually best and quickest means.  

Edited December 23, 2021 by Plymouthy Adams

[Jerry Roberts]

14 minutes ago, Doug&Deb said:

Which wire are you referring to? Something in the distributor?

There is a little wire in the distributor that has to move each time you use the throttle . It goes from one plate to another and is very flexable . At idle it could be OK but when you use the throttle , one of the plates moves and the wire moves too . 

[Plymouthy Adams]

the plate only moves with vacuum advance....the spring loaded flyweighted cam does the advancing mechanically at this point moving the breaker cam...

[Doug&Deb]

Got it. The distributor in the car is incorrect for the year. I have a correct IAT-4011 to install. I will change the condenser on the current distributor to see if that corrects the problem. It’s still a good distributor. Never hurts to have a spare.