Jeep Carb is flooding

[dougimes]

I am struggling with a nagging problem.

Carter YS carb on an M38a1.

Symptom-
Starts fine
Runs fine
after driving nicely down the road at speed, I come to a stop sign.

The jeep idles nicely for about 10 seconds and then starts to load up, and dies. At this point, then engine is badly flooded and will not start unless I cut off the fuel supply to the fuel pump, and then crank it, treating it as if it were flooded.

The carb was rebuilt when I did the restoration
I have taken it apart trying to diagnose this, thinking the float was sticking and the bowl was flooding. cant see a problem (doesnt mean there isnt one)

This problem just started cropping up- ran fine for a few hundred miles after Restoration complete.


any ideas on what the problem is?

are there any other circuits in the carb that can flood the engine so dramatically?

this has been killing me, dies while in traffic lines on hills.

 

[73m819]

choke is sticking, not open all the way, dirt in the float needle valve, not closing all the way

 

[jeepin]

I would lean toward needle and seat. Check float adjustment, is needle seating all the way? Does float have a pinhole? I can't think of another circuit that could put that much gas into the intake in such a short time (especially if you don't have an electric fuel pump) The YS/YF are so simple its frustrating when you can't get them tuned...believe me I have the t-shirt.

 

[papabear]

I would lean toward needle and seat. Check float adjustment, is needle seating all the way? Does float have a pinhole? I can't think of another circuit that could put that much gas into the intake in such a short time (especially if you don't have an electric fuel pump) The YS/YF are so simple its frustrating when you can't get them tuned...believe me I have the t-shirt.

Had that same problem with my 1953 M38A1.
Seat had a TINY bit of trash.

 

[NDT]

Mine used to do that. I think it is caused by very fine crap causing the needle to stick. Try an in line filter right before the carb.

 

[plym49]

If you don't find the problem in the carb, check to see if your fuel pressure is too high.

I have also set the float a little lower on carbs that did what yours is doing. It gives a little more leverage on the needle.

 

[Asgar]

I had massive flooding after a rebuild, the new float needle valve was the neopream tip type with solid shaft, the old was the solid brass point with a spring loaded body. I fiddled with the old one a few times but it keep on flooding from time to time. There was something about the geometry of the end and the wire retainer hook to the float, it would hang up. I swapped back the original solid point / spring plunger type float valve and I have not had any problems since.