Diapharm in Pitcock

[Anonymous]

I know I know, we can't seem to get away from the infamous pitcock but here is another one for you guys. I have rebuilt the pitcock - new everything in it. I turned it to the run position and sucked on the vaccum line. A little bit of gas dribbled out and then nothing. :? So I started sucking and the taking a breath....sucking and then taking a breath : trying to simulate the engine vaccum. I got a little bit of gas each time but not alot. How much should I get out of the pitcock when I suck on the line? Should the gas just flow out, since the piston is pulled away inside? When the bike was in the on postion I would ride it for a mile or two and then it would act like it ran out of gas or flood out. I just want to make sure I have it fixed before I slap the tank back on. Anybody got any ideas?

Josh

[SqDancerLynn1]

The human body cannot produce enough suction.. If you did not get a mouth full of gas I would say that it would be ok

[TheNose]

I can suck on mine, and with very little vacuum have gas flow from the petcock. If you have a prime position, turn it to prime and you should have a continuous gas flow. You should have the same flow when you suck on the vacuum line. You might have a clogged filter inside the tank on the tank side of the petcock. Did you check this filter? You may not have put the petcock back together correctly. Might want to recheck your work. I know it's frustrating, because I went through a lot of fuel problems too. Keep looking, it's a simple process. You can do it.

Terry

[moto_dan]

If in Run position, be sure you have more than a gallon or so of fuel, if low on fuel try the Reserve position and as stated previously you should be able to get a stream of fuel while applying a vacuum.

[Billy Ricks]

There is a small rod with about one-half turn of spring built into it on the lever side of the diaphram. You probably need to pull it to make it a little longer so it pushes on the diaphram a little harder. Be careful when you take the lever assembly apart. Pull it straight out so you don't mangle the rod.

[kz]

Then I checked my spare tank with water (including petcock) I was able to suck at the vaccum line (by mouth) and check the petcock.

It was enough to suck this way and see that the petcock worked correctely.

So if you suck with your mouth at the petcock vaccum line, the petcock should open the fuel channel (at least if the tank is filled whith water).

[Anonymous]

I had my tank off today,and there is a steady stream of fuel with a constant vacuum on the line (by mouth,and not too hard)Also a steady stream from prime ( no vacuum..of course) Also on reserve with a vacuum there was a steady stream (well, not at first, but thats the prob i was after )I was having probs on reserve with running out of fuel b4 it was empty.Also found out that prime feeds from the reserve tube so I'll know how to get home if it happens again...
Steve

[Anonymous]

Petcock

I am just waiting for my rebuild kit to come in ,ordered it yesterday , and judging how thin the vacuum diaphram is in the petcock you should be able to suck on the vac tube and see full fuel flow from the petcock.Let us now how you make out.

[Anonymous]

I have reassembled that stupid petcock again and when I sucked on the vaccum line it still does not function properly. I am thinking that there must be some sort of a crud ring that the rubber oring is hanging up on. The good news is when sucking on the vaccum line I am no longer getting gas in it. So I guess I will have to pull it apart again. Anyone have this problem? I am becoming slightly frustrated. :?

[Anonymous]

I have reassembled that stupid petcock again and when I sucked on the vaccum line it still does not function properly. I am thinking that there must be some sort of a crud ring that the rubber oring is hanging up on. The good news is when sucking on the vaccum line I am no longer getting gas in it. So I guess I will have to pull it apart again. Anyone have this problem? I am becoming slightly frustrated. :?

[Anonymous]

Have you tried it in the prime position yet? Does fuel flow that way? The diaphram and spring in this petcock are not that large, so it takes very little suction to open it fully. You may want to blow out everything without the diaphram installed to make sure it is open in every orfice. It's a pretty simple device, so it has got to be something stupidly simple -- and I hate those. Gosh, if I had a nickle for everytime...

[Anonymous]

Thats what I cant figure out. It flows nice in the PRIme pos. and in the REServe pos. But once I put it in the ON pos and suck on the vaccum line, it'll spit a little gas and then no more after that.(all while I am still suckin' on that dang hose). I rebuilt it last week. I should be able to suck the piston out and the gas should flow freely while in the on pos. for as long as I am sucking right?

[Anonymous]

Well, at least you're narrowing it down. Are you sure you have enough fuel in the tank to be in the "RUN" zone? Both Prime and RES are picking up from a lower portion of the tank.

It's been a while (2 yrs) since I had mine apart, but the only difference I recall with any of these is the height of the pick-up in the tank. Check that the RUN line into the tank is free of blockage too.

Roger

[Anonymous]

i am thinking that there might not be enuf gas in the tank. i completely forgot about the different pick up points on that thing. i will have to check that.

Thanks alot for your help.

Josh