Pet is going bad, is it "safe" to operate the bike with the pet on "PRIME"?

[Rust_to_Redemption]

My pet which I replaced 2 years ago with a "OEM" (I think it was a fake since it failed so quickly) is failing. On my way to work this morning I got the "you're running out of fuel" sputtering, but switching to Reserve did nothing. I had also just filled up yesterday so I didn't think I needed to be at Reserve quite yet anyway. I switched it over to Prime which solved the problem for the time, and continued on my way to work. I did a quick and dirty test in the parking lot and it doesn't flow enough fuel when in the "ON" position to run the bike, barely a trickle. It will run perfectly when in "prime". The way I understand it the "Prime" setting operates like a gravity fed pet set to ON, is there any detriment to running the bike with it set to prime until I can get a replacement installed (thinking of going pingle this time)? I know not to leave it on Prime because of leakage issues, I assume the ON or RES setting would act like OFF?

[bccap]

The on or reserve does act as an off position when the bike is not running... But with a failed petcock you may get gas in your oil sump.....Check oil for gas in it and if there is do not run it.........

[Gorminrider]

Yes, it's ok to run with Prime. and it's ok to turn off the gas with the other two positions.

Yes, If your float needles are in good condition, they should even hold the gas back when you park the bike, at least short term, but yes. It is much safer to turn the petcock "off" with the other positions just as you say.

If you find the float needles are NOT in great shape, a lower level in the tank will help. A lower level in the tank reduces gravity fuel pressure...

PS: why bother with a pingel tap if your vacuum tap is already functioning as one!

You mmight also try taking your tap apart. It might have a bit of crap stopping the o-ring on the plunger from working properly.

[Rust_to_Redemption]

I will be sure to check the oil level before I take off, and not run it if it is higher than where it is supposed to be, meaning gas is leaking into the oil. Being that the failure is it not flowing enough gas makes me feel a little better about the odds of it filling my crankcase with gas. I haven't taken it apart yet, but I bet the gasket has swelled and that is why it is not flowing fuel appropriately anymore.

[Steve]

There is also a possiblity that the vacuum diaphragm has failed. Vacuum simply can not open it far enough to flow any fuel.

The RUN and REServe positions require vacuum to pull a small plunger out of a hole that blocks fuel flow. The PRIme position mechanically pushes that plunger out of the way. If you don't get enough fuel flow in ANY position, might be time to pull the petcock to check that the filter screen is not plugged.

By the way, that filter screen is supposed to keep water out of the system, too. You might have a bunch of water in the tank, the filter is doing its job holding the water back and not much gas can get through. It's worth a check before ordering another petcock.

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[Redman]

in addition to what others have said:

Let me say it this way; Yes, is safe to operate bike in PRIme position. But, no, is not safe to leave the bike parked in PRIme position.

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[hannibal]

Make sure the vacuum hose hasn't come off and is not kinked or torn.

[Rust_to_Redemption]

There is also a possiblity that the vacuum diaphragm has failed. Vacuum simply can not open it far enough to flow any fuel.

The RUN and REServe positions require vacuum to pull a small plunger out of a hole that blocks fuel flow. The PRIme position mechanically pushes that plunger out of the way. If you don't get enough fuel flow in ANY position, might be time to pull the petcock to check that the filter screen is not plugged.

By the way, that filter screen is supposed to keep water out of the system, too. You might have a bunch of water in the tank, the filter is doing its job holding the water back and not much gas can get through. It's worth a check before ordering another petcock.

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The tank was completely empty and dry this past winter for painting, and I don't use anything but 100% gas. I add fuel stabilizer if its going to be sitting more than a week, which is overkill but I don't like dealing with crappy carbs. I think I can probably rule out water.

[Rust_to_Redemption]

Make sure the vacuum hose hasn't come off and is not kinked or torn.

Vacuum hose is three months old so the likelihood of tears/holes is slim, and secured with ring clamps. I did check to make sure it was still attached at both ends, and it was.

[Steve]

Ok, you have eliminated at least a couple of items, but there is still the vacuum diaphragm inside the petcock.

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[Rust_to_Redemption]

Ok, you have eliminated at least a couple of items, but there is still the vacuum diaphragm inside the petcock.

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I agree, I still have a couple things to check, all of which require me to tear down the pet. I still have to ride it home this evening, but I will be tearing into it to further diagnose the problem when I have time.

[LAB3]

Hmmmm, maybe you got a tank of bad gas yesterday?

[bobgroger]

Also check to see that the vent in the gas cap isn't clogged. Run the bike until it sputters, open the cap. If you hear a Whoosh the vent is plugged.

[Rust_to_Redemption]

Hmmmm, maybe you got a tank of bad gas yesterday?

Probably not, since the bike runs perfectly on PRIme.

[Rust_to_Redemption]

Also check to see that the vent in the gas cap isn't clogged. Run the bike until it sputters, open the cap. If you hear a Whoosh the vent is plugged.

Wouldn't this also effect the ability of PRIme to deliver the gas? If I run it in the "ON" position it will start sputtering after 5-10 minutes (I'm assuming time it takes to run the bowl empty; if I run it in PRIme position it will run at least 45 mins with no sputtering.