Question
Carburetor
B&S model 170402, Type 0714. It has a 2 piece FLo-Jet carburetor.
My snowblower would not start last year, so took the engine off to work on it. After cleaning the carburetor, I put the engine back on about a month ago and it started with a couple pulls of the cord. Idled fine. When using it during the first snow storm it ran ok, but wanted to stall when I hit snow. If I pushed down on the handles to lift up the front end a bit, the engine would get back up to normal speed. After awhile it began to run ok. Could this be because it was warmed up then?
A couple weeks later when I started it, it idled fine, but the second I lifted up on the handle to engage the auger, the engine stalled. It did this several times. If I push the handle back down quick enough, to disengage the auger, the engine speed went back to normal. In other words it would idle ok, but stall when the auger was engaged.
Today I couldn't get it started at all. It would almost start. Take a look at the attached photo. The yellow arrows are on a square tubing that attached to the bottom end of the carburetor. When I looked down inside that tube, gasoline could be seen pooling up at the bottom. It seems to be running straight through the carburetor. If that square tube wasn't there, the fuel would be running out onto the ground.
What would cause this? Does the carburetor need more cleaning or a rebuilding?
I have the needle valve at the bottom turned out 1 1/2 turns and the idle valve turned out 1 turn.
AnswerI would clean again. Does your inlet needle have the rubber (viton) tip? If so, did you replace the needle?
Is the float alright? Briggs floats are pretty reliable compared to Tecumseh but once in a while I find a leaky float. Holes in the float allow gas to enter and then the float gets too heavy.
One tip to repairing these carbs it to lap the high speed jet seat to ensure it is sealing. You can take the old high speed jet and grind off the threads. Use lapping compound on the jet taper and lap the seat to make sure the surface is smooth. You will have to replace the jet with a new one that has threads on it.
I have also had other mechanics tell me they use a number 2, regular pencil, to lap the carburetor high speed jet seat. Just sharpen the end of the pencil, break off the exposed lead and you are left with a taper that can be used to lap the seat. Lapping the high speed jet seat is difficult to explain how to do but is very easy to do.
These old carbs work great when you lap the high speed jet seat and replace the inlet needle seat. Replacing the inlet needle seat is difficult to explain and difficult to do...I only replace if absolutely necessary.
Let me know if cleaning the carb, replacing the inlet needle, checking the float, and lapping the high speed jet seat fixes the problem.
Eric
