Carb problems

[loco]

Last summer I bought a '92 Suzuki GS500E and I've been trying to get it ready for some summer time riding.  Last year it was running and over the winter I worked on some of the paint.  But anyway a couple of months ago I went to start it, it had been sitting over the winter, and it wouldn't start.  It would start if you sprayed starting fluid in the breather but than it would die.  So I went ahead and put in carb kits and put it all back together.  Same thing though, will start with starting fluid but than dies.

I've double checked my hose routing and they all seem to be going to the right place.  The vacuum hose is going to the left carb and the fuel line is going to the lower connector between the carbs.  I can see gas in the filter between the shut off valve and the carbs.

So I'm at a loss.  It doesn't seem to be getting gas in carbs, but there is gas in the filter prior to getting to the carbs.

Chad

[JAY W]

Is it a gravity fed fuel filter or is a car type one?

[loco]

It appears to be just a standard inline fuel filter.

Chad

[mister]

Remove the filter and see how it goes.

Michael

[JAY W]

ok you can easily eliminate the filter (most avoid fuel filters on the GS as prone to iffy vacuum prob`) by undoing drain screws on carbs/pulling fuel pipe off carb to check gas is getting to carbs.
When you fitted carb kit did you clean pilot jets/main jets?

[loco]

Okay I will try that.  And yes I cleaned the jets and the bowls real good.

Chad

[JAY W]

If you crank it over and won`t run,whip the spark plugs sharpish and see if your plugs are wet.This obviously will tell you if its fuel related.If plugs wet do a spark test,if good as your bike has stood i`d then check the air jets in the backs of the carb are clear with compressed air.If you have carbs off and haven`t already check float height.

[loco]

When I get home tonight from drill I will go ahead and look into the fuel filter.  The more I think about it the more I feel that is where the problem is.

Chad

[Jared]

When you say you cleaned the jets.....you physically took them out of the carbs- cleaned them  so you could see daylight through them  ( the pilot jets specifically )?
make sure you clean all of the orifices  in the carb bodies too. Fuel evaporates out of the bowls and leaves all the additives in the fuel behind to clog up all the small orifices  etc in the carbs.
Might as well check everything while you have them open ( might be worth your time to do a "rebuild" now too...) :  http://www.partsnmore.com/parts/suzuki/gs500/  part #48-1947

Fresh fuel in the tank?

[loco]

I took the carbs all the way down and put a kit in them and adjusted the float height, as outlined in the manual. 

BTW the filter wasn't the problem.  I'm going to take the petcock apart and make sure it is not clogged.  I'm not getting good fuel flow to the carbs.

Chad

[loco]

Okay I finally got it running tonight.  I took the petcock off and apart and cleaned it and it still wouldn't stay running.  Finally I put it all back together and this time I put the air filters on.  Once I got it cranked and fuel flowing to the filters it ran.  Idle is a little bit high, only about 8 grand  , but at least I can start tweaking it.

BTW does anyone have a diagram of how the petcock goes back together.  I wonder if the high idle could be due to the diaphragm and spring in wrong.

Chad

[loco]

Here is a thought.  What I thought was "Off" is really "Prime", which from what I can tell gives it unrestricted fuel flow.  That is what the engine is running 8K at.  When switching over to reserve of on it idles down and that dies from fuel starvation. 

I may either have the fuel petcock together wrong or it just needs replacement.

Chad

[Big Rich]

Your 8000 rpm idle isn't caused by the petcock being on prime. Unless the fuel is pushing the slide up while simultaneously pouring directly into the cylinder. Which it's not.

[loco]

What else could cause this than?  When I put the carb kits in I check and adjusted the float height as per the manual.

Now there could be a problem with the diaphragm in the petcock.  From what I understand the amount of fuel to the carbs is ran off of a vacuum (line from the left carb) and this diaphragm is what controls that fuel flow.

Chad 

[jp]

The vacuum line from the carbs to the petcock controls the fuel flow. If you don't have good vacuum, the flow will be restricted. As your bike seems to run OK on prime, the vacuum line is where I'd look. But first, I'd just leave it on prime while adjusting the idle. If a new vacuum line from the carbs to the petcock doesn't fix the fuel flow problem, then it's probably the petcock itself. I would replace it rather than rebuild it, but it's your dime.

[Big Rich]

Sorry, I should have specified. If your choke cable (fuel enricher/ whatever) is stuck, it can cause the idle to be high. I don't know about 8 grand, but high. Most likely it's your throttle cable snagged up somewhere.

[loco]

Just wanted to add the problem/fix here in case somebody in the future pulls this up in the archive looking for a similar problem.

The problem was the throttle cable was in a bind at the throttle.  Took the twist throttle apart and fixed it and it is doing fine.

Chad

[scratch]

http://gstwins.com/gsboard/index.php?topic=312.0