Bad Petcock

[Anonymous]

Ok.....i'm pretty sure but i want to get a concensus on this.....

i have a problem with gas leaking which i think i have traced back to the petcock but maybe not.....

on PRIME fuel runs out
on RES fuel runs out
on ON fuel doesn't run

so if its completly shot i was expecting both ON & RES to allow fuel to run, could it be partially shot ? or could i have tripped the vacuum by switching back and forth beween prime etc (doesn't sound likely i know)

and the other peice of the puzzle is that when it leaked on me it was in the ON position....

i was originally thinking a stuck Float problem but with this (what seems to me) wierd petcock function i'm not sure.....

any heard of this kinda issue..?

Thanks

Phil

[Billy Ricks]

If it is a problem of fuel continuing to flow from the petcock then the problem is with the diaphram in the petcock. The diaphram either has a hole in it or there is a rod that pushes on the diaphram that needs adjusting. On the right side of the diaphram is a spring to return the diaphram to a position to shut down fuel flow when no vacuum is applied. On the left side is a rod with about a half loop of spring built into it. This is probably where your problem lies. That rod is moved by the lever so the prime position allows fuel to flow. You can vary the length of that rod to get the petcock working properly again. When you take the petcock apart be careful and pull the guts straight out or you'll mangle that rod. You get to the barrel valve and the rod by flipping the ears of the plate under the lever over their tabs.

You'll know you have it adjusted right if when there is no vacuum fuel doesn't flow in the on or res postitions. Attach a piece of vacuum line to the vacuum fitting on the petcock and suck on it. Fuel should flow with vacuum applied. It should also flow with the petcock lever in prime position. Lat the fuel flow into a gas can.

[Anonymous]

the rod thing sounds likely....now i think about it the petcock used to be impossibly stiff to move but was easily moved last night...like maybe something shifted inside......

[ard]

bad petcock

I had a similar problem, the pet cock was dry even if the tank was full, but once I attach the fuel line and vacum line it starts leaking leaked on the engine and soaked all the filters. (I dont know if the problem was related) I finally got a brand new petcock for $45.00 on ebay now I have a dry engine and filters.
The reason I went with new one, was the price of the kit. I did not know if the repair kit would have taken care of this problem. and the price was about $22.00, so for $45.00 I went to the new one. Good luck
ard 8) 8)