Petcok on an '80 GS850GL

[Darci]

I just installed the petcock on my tank, hooked up all the lines and tried to fire it. I put the petcock on what I thought was prime. I noticed that the screw on the petcock will allow me to turn it several times clockwise and counterclockwise. How will I know when the thing is on prime or on? Do I have to screw it in all the way for prime?

Thanks..

[Steve]

"the petcock"...is it a stock replacement or aftermarket?

If it is a stock replacement, pointing the tab toward the rear of the bike is PRIME. Straight down is NORMAL and forward is RESERVE.

If it is an aftermarket petcock, I would say "read the directions", but since you are asking the question, it is apparent that there were none.

Easiest way to find out is to attach a hose to the petcock and place the other end in a fuel-proof container. Turn the knob and watch for fuel flow. Is there a vacuum connection to the petcock? It might even be possible that this (aftermarket) petcock is simply ON/OFF, with no PRIME or RESERVE settings. :roll:


.

[chef1366]

You have the 80 petcock which does not have a handle but a slot. Prime is at 12 and 6 oclock and run is 3 and 9 oclock. On these petcocks you need to have vacuum even on prime activate the gas flow. Put the petcock on prime and suck on the vacuum line going into the petcock to fill your float bowls for a few minutes and then try to turrn the bike over. If you get gas in your mouth replace the petcock. You can turn these around and around and it won't make any difference, just the position does.

[Darci]

"the petcock"...is it a stock replacement or aftermarket?

If it is a stock replacement, pointing the tab toward the rear of the bike is PRIME. Straight down is NORMAL and forward is RESERVE.

If it is an aftermarket petcock, I would say "read the directions", but since you are asking the question, it is apparent that there were none.

Easiest way to find out is to attach a hose to the petcock and place the other end in a fuel-proof container. Turn the knob and watch for fuel flow. Is there a vacuum connection to the petcock? It might even be possible that this (aftermarket) petcock is simply ON/OFF, with no PRIME or RESERVE settings. :roll:


.

Thanks, but it I have an automatic petcock. I have no reserve!

[Darci]

You have the 80 petcock which does not have a handle but a slot. Prime is at 12 and 6 oclock and run is 3 and 9 oclock. On these petcocks you need to have vacuum even on prime activate the gas flow. Put the petcock on prime and suck on the vacuum line going into the petcock to fill your float bowls for a few minutes and then try to turrn the bike over. If you get gas in your mouth replace the petcock. You can turn these around and around and it won't make any difference, just the position does.

Thanks. The bowls are filling, so that tells me the petcock is working ok. This is the first bike I have owned that has an automatic petcock. All my others had "regular" petcocks.


I have a feeling, what I need to do, is remove the carbs, look at the floats. The bike had been sitting for about 2 years. It was a gift from a friend. There may have been something I missed when I took the carbs off previously to clean them.

Thanks!:-D