New petcock, no vacuum

[fsindsen]

Help

I have replaced my stock petcock with a universal on/off type since the old one failed.

i have plugged the vacuum hose on the carb housing thingy.. (gt380, 1977) but gravity only gets fuel to carb 1(cyl1) it starts but still no help. it ont fire on the middle and third. (gets no fuel) all carbs are newly cleaned and renovated. no blockage.

anybody??

thx

[2strokelove]

Any petcock with multiple exits to the carbs will normally only flow from one line. But when that carb bowl fills then the fuel will flow to the next pipe and so on. The others will flow a small amount but only one will really flow fuel. To test what I'm saying take all three lines from the petcock and put them in a fuel can. Turn the petcock on. As fuel flows from one line pinch it off and the flow will move to another line. If you pinch 2 slightly the fuel will flow from all three. You pinching the line is acting like the needle and seat in the carb bowl. If you have a carb with a stuck closed needle then fuel will never flow to it or a plugged vent to let the air from the bowl as fuel fills it. The fuel will always take the easiest route. I hope this makes some sense??

[fsindsen]

ill try adjusting the floats again... and do a tripple check on the flow

thanks, ill let ya know.