Gas leakage

[Ohioan]

1983 GS450T

Gas is siphoning out of the tank, through the carbs, and out hose in the back of the airbox. The petcock is turned to PRI and the choke is off. What could cause this?

I'm going to take the carbs apart, and clean them and replace the o-rings, just curious if I'll need more parts.

[Guest]

Take it off prime. when it is on prime it allows the gas to flow freely.

[jjmaag]

Turn off the prime. It should be in the on or reserve position. If it still leaks check the needle and seats and float height.

[Ohioan]

ahhh, I thought PRI was the off position. Eh, I have little experience here. The Nighthawk I rode previously had a off, on and reserve position.

I ASSUMED that PRI was off, so I made a ass out of me and you.

[jjmaag]

Prime is used for filling the float bowls when they are empty. The engine vaccuum opens and closes the petcock for normal use.

[jimcor]

...and they should have made 2 vac petcocks for the entire motorsickle world and thrown them both away!!!

Trouble, trouble trouble.

[chuckycheese]

Yep

...and they should have made 2 vac petcocks for the entire motorsickle world and thrown them both away!!!

Trouble, trouble trouble.

Amen, amen, amen!

[Ohioan]

...and they should have made 2 vac petcocks for the entire motorsickle world and thrown them both away!!!

Trouble, trouble trouble.

Huh? Explain please?

[jimcor]

Huh? Explain please?

Sure.

Manual petcock, which requires you to turn the lever to on, off or reserve doesn't have a diaphragm that dries out and gets hard or a vacuumn line that gets hard and leaks or breaks affecting the petcock and the carbs.

Vac petcocks are a pita. Expensive too.

[Ohioan]

Is it possible to change from vac to manual?

[Guest]

yeah you just need to plug the vac. hole on the carb so that it dont suck air.

[SqDancerLynn1]

Two problems, carbs and petcock. Turn petcock to on position, fix the float needles

[jimcor]

yeah you just need to plug the vac. hole on the carb so that it dont suck air.

That will not work. Without the vacuumn the diaphragm will remain closed except in the prime position. So no more reserve and if the rubber doesn't seal completely it will still leak in the on and reserve position.

You could go through the hassle of buying an expensive Pringle petcock and adaptor plate or just bite the bullet and spend (mine was $70) the bucks on a genuine Zookie part. Don't waste your money on ebay look a like parts and rebuild kits lot of reports of trouble with these.