Leak

[peterd123]

Just started the GS850. Been standing up for winter. I noticed that there is a leak from the far left carb onto the engine, leaving a brown stain. When i run my hand under the carb, there is a brown fuel smelling substance there. Could this be a sticking float? Or something else?
Regards
Pete

[earlfor]

Just started the GS850. Been standing up for winter. I noticed that there is a leak from the far left carb onto the engine, leaving a brown stain. When i run my hand under the carb, there is a brown fuel smelling substance there. Could this be a sticking float? Or something else?
Regards
Pete

If the petcock was shutting off fuel flow as it should with no vacuum present, the carb couldn't leak. If the float needle/fuel inlet seat was not leaking it couldn't leak fuel even though the petcock was leaking. Brown fuel is usually indicative of gas being at the varnish stage. so at the very least, you have a faulty petcock, a stuck or leaking fuel needle valve/seat and varnish in your tank.

[peterd123]

Thanks, will flush it out.
Regards
Pete

[peterd123]

The tap on my tank does not have anything to turn on or off.
Regards

[steve murdoch]

Sounds like your bike is an '80.
A bit more info on that petcock.

https://www.thegsresources.com/_forum/showthread.php?206025-1980-GS850-GL-petcock

[Guest]

Your fuel tap will have 'on' and 'prime' positions. Make sure it is not set to prime (even though this still needs a vacuum to get it started)

If your trouble lies with the fuel tap then a new replacement is the best answer. Rebuilds and repair kits don't usually do the job. Ask me how I know.

As has been said, you also need to clean the carb(s). Be prepared to do it more than once until it is right. While you're in there check the o ring on the needle velve set up.

[wymple]

"Your fuel tap will have 'on' and 'prime' positions. Make sure it is not set to prime (even though this still needs a vacuum to get it started)"

This isn't registering on my brain. What is the good of a prime position if it still needs vacuum? I'm missing something?

[Guest]

"Your fuel tap will have 'on' and 'prime' positions. Make sure it is not set to prime (even though this still needs a vacuum to get it started)"

This isn't registering on my brain. What is the good of a prime position if it still needs vacuum? I'm missing something?

It just needs a quick crank to generate a quick bit of vacuum open the valve diaphragm and then the prime will flow.
In the ON position it would need a lot more cranking over to get fuel to the carbs. All explained in the pic below.

fuel tap.jpg

[peterd123]

The registration document say 79. Thanks for the info.

[peterd123]

The diagram says to change to on immediately, how do i do that, there is no switch or leaver.?

It just needs a quick crank to generate a quick bit of vacuum open the valve diaphragm and then the prime will flow.
In the ON position it would need a lot more cranking over to get fuel to the carbs. All explained in the pic below.

[ATTACH=CONFIG]54085[/ATTACH]

[peterd123]

20180224_184644_resized (2).jpg

The diagram says to change to on immediately, how do i do that, there is no switch or leaver.?

Just taken this picture. Engine fairly cold now and not running. Went for a short run today for the first time since buying the bike. No leaks at moment. Lets see if there are any tomorrow. Think it came from the hole in the petcock.

[Guest]

The diagram says to change to on immediately, how do i do that, there is no switch or leaver.?

Small flat blade screwdriver in to the slot. 1/4 turn will change from prime to run.

[Steve]

If your title or registration says it's a '79, they are probably basing that on production date, not the model year.

Production of the 1980 bikes started as early as August, 1979. Some say that it might even be July, I don't know.

Also, based on that photo, it appears that you have the L model. Might be helpful if you generate a signature that will show in every post you make, that says something like "Current bike, 1980 GS850GL".

.