No gas!

[brian kirby]

I would just get another carb, that one is never going to work right. If you stick with that one, use another Mikuni needle/seat trying to make the Bing part work when its already been modified for the Mikuni part is pointless.

Brian

[Andreas Piepke]

This took a while! To fix the problem with my float needle (a Mikuni needle in a Bing carburetor) the people from the Bing Agency build a new float needle seat and installed it in my carburetor body. Here a photo of the new modified assembly:



Now I can install a Viton tipped Bing float needle. I just tried this out on the bench and found the needle to seal properly. I adjusted the floats to be vertical when resting on the needle, which translates into about 40 ml of gas in the float bowl.

Andreas

[skiracer]

Andreas,

Have you check to see if the gas is running freely through the gas lines without being attached to the carb?  I once had a case of my gas cap on the tank being too tight, and not allowed proper venting, so the gas would not flow through the gas lines....  Also, how good are your petcocks?  They too might be restricting the fuel flow....

1976 MC 5 Original Owner
1982 Suzuki PE 175
1976 Penton 175 XC

[Andreas Piepke]

Thanks fot the input. The gas lines are free and there is sufficient flow. Both petcocks are new. I checked flow by draining the tank content through the fuel lines.
I think the fuel problem is solved now. I even managed to start the engine, probably for the first time in decades. In the process I discovered two new problems I need to fix:
1) The clutch doesn't separate. I will remove the clutch cover for inspection.
2) The engine sems to rev extremely "tired". I'll re-check ignitin timing and compression. What pressure should a rebuilt 250 ccm engine (1973 vintage) deliver?
The cylinder has been bored, new piston, connecting rod and bearings installed. The engine should run well once it's propely set up.

Cheers

Andreas

[Dale Sonnenschein]

Compression should be 160 to 180 with new bore and piston. Might be a jetting issue. Sounds lean.

73 Jackpiner
73 Husky 360 WR/RT
76 Husky WR360
78 husky cr250
10 ktm 250xc
02 bmw r1150r

[Patton]

Thread hijack.

Pulled up this thread searching for petcock answers (the best way to replace, least expensive, etc.) and found this post showing everything one needs to know, pictures included, about a Bing 54.

Thanks for all of the detail, advise to owners,  and clear photographs.

RP