Carb Question

[sick48a]

Well I finally got my 48 A back into service. I replaced the clutch pulley bearing and race. I replaced the drive end on the starter. I put in a new set of plugs.

I took it out to mow today, first time its done work since this spring. I put in fresh gas and some Gumout gas treatment. Made a few passes and adjusted the carb some.

It runs good under a hard load but will miss and pop and black smoke when I hit a bump in the field. Float to high or is the float needle not sealing good? It never did this when I used it for plowing and mowing in the spring.

It has new points and condensor and they are set properly. Distributer cap is wore out though so I need to get a new one and make new spark plug wires for it. Spark at plugs is blue when tractor is cold, spark is orange after tractor is at operating temp so my coil is getting weak.

Thanks for any ideas, sorry for the long post.

 

[Kurt_JDB]

Sounds like you might be getting gas up the bowl vent when you hit a bump. In the late B series carbs there is a baffle in this vent to help prevent this. yours could be missing or gas is getting through it. The vent is near where the stem joins the body. Parts book or the overhaul manual has a picture of it.

Kurt

 

[sick48a]

This carb was overhauled by Burrey's Carburetor service. He has done three carbs for me for other tractors. This carb was done three years ago. When I went to use the tractor this spring the float had a hole in it. So I bought a new one for it, bet I got the float to high and its doing what you said.

 

[Mike M]

Those later models call for a 3/8" float level , but I set them to the 1/2" of the earlier models to avoid the very problem you discribed. If you can get 7/16" that may be fine too.

 

[sick48a]

Well I just came back in from taking the carb apart. Float level is exactly 3/8, should I go ahead and lower it to 1/2?

I put this float in new this spring from Roberts Carb repair. It has a pin hole somewhere. I can barely hear fuel sloshing inside. I never found the hole. I put the float in a bucket of water, it floated good, but still there is some fuel in there I am pretty sure. Unless its particles of solder moving around.

 

[teddy52food]

Hold the float in some hot water. The pin hole will bubble just like a leaking inner tube.

 

[sick48a]

I held the float in a sink of hot water this morning. No bubbles to be found anywhere. So I went ahead and lowered the float to 1/2.Stuck it all back together this morning, went and mowed in a rough part of the field, seems like problem is solved.