1986 GS550ES

[Anonymous]

HELP!!! I fired up my 86' GS550ES for the first time in a year and sounded great(4 into 1 pipes). Took it out for a quick spin and trouble. It died on me before i left the subdivision. After getting back home I noticed fuel dripping from the filterbox. Has anyone out there had this happen and what is the cure? :x

[HiSPL]

Did you just install the 4-1? Did you drain the gas before storing? It sounds like maybe it was left on prime and overfilled your carbs, which can soak your airfilter when left on the side stand.....Then it will flood out the engine as it suck fuel off of the air filter.........

[Anonymous]

I had the same thing happen to my 83 550es this spring. I pulled the float bowls and checked for varnish(dried out old gas) on the float valve cleaned them put it back together, and it seemed to do the trick.

REMEMBER to change your oil right away once you have fixed it because if the raw fuel is flowing down the throut of the carb when the engine is off the it will run down in your sump and thin your oil out to water-like thickness. You can imagine what starts happening next!

[Anonymous]

I did install the 4-1 myself. I left the fuel dial on "RES". Im thinking now from the replies that old fuel is causing the problem as well as maybe a bad fuel dial? I cleaned the carbs with carb cleaner and now it won't start. This might be caysed by fowled plugs. Anymore hints would be appreciated. Thanks ............. :?

[Anonymous]

HiSPL, I miss understood your question. I had the 4-1 on and off for fitting purposes and decided to leave it on once I was happy with the fit. At one point I thought I had too much back pressure which was causing the problem? Thanks

[HiSPL]

Pretty much all the 4-1's will have less backpressure. Even the Mac's that claim "no rejetting required". However your problem sounds like its running rich which points toward a faulty petcock. Disassemble and clean your petcock. Check that it doesn't flow when there is no vacuum and that it does flow when vacuum is applied. Also be CERTAIN that the diaphragm isn't leaking. Because that will dump gas into the no.2 cylinder and your crankcase. Also is it possible that it was running on the fuel in the carbs and that it didn't get fuel from the tank? I know my 750 will get me a half mile down the road before dying if I forget to turn on the gas.

Good luck

[Anonymous]

HiSPL,
Awsome info. Thanks. Well, on my 86'GS petcock, you have the selection of either "PRI", "ON", or "RES". So one of them must be selected when running(ON or RES). When I crank the engine, I cannot see any fuel going to the carbs, so your idea od a faulty petcock sounds right. A little side note, I also had an ongoing problem with the engine idle. Seems after the engine was warmed up, at a stop light the idle would hunt. It would go to about 2000 rpm then back down and so on. The fuel looks like it's coming from the 1-2 cylinder carb as it is only a 2 carb set-up. Thanks again for your replies.

[Anonymous]

1986 GS550ES Flooding problems

OK, I cleaned the carbs over the weekend. Is green gas a bad thing? I must have cleaned every orifice I found and then some. I also removed the old fuel out of the tank along with as much of the rust as possible. Installed an in-line fuel filter and cross the fingers that my flooding problem is cured. I will try to give it some spark and let everyone know if it works.

[Anonymous]

Carb Problems

S*%T!!! It fired right up and fouled the plugs in the process. What now, Float Height?

[lhanscom]

It could also be your o-rings that go around the float valve. If they're leaking, float height doesn't do anything. Also, this is just a guess, if your carbs overflowed and soaked your air filter, it may cause an overly rich condition?, Maybe? I'm really guessing here. You could try popping out the filter and see how she runs, just know that she may not run at all with it out, just worth a try, for troubleshooting sake.

[Anonymous]

carb flooding

Well, good idea. I was getting a soaking of fuel in my filter box with my old K&N filter. I think the cause of this was an overly soaked (filter oil) air filter. So I ditched the K&N and went back to an oem filter. I think that trouble is gone, but it still run's rich. Where is the Float valve "O" ring located? Is this the float needle assy.? I m taking the carbs out again tonight as Im thinking that this can't be this difficult of a problem to solve. I haven't touched the float height at all so Im pretty sure it's ok. Thanks.....

[lhanscom]

Yes it's part of the float needle assembly. You should have a screw under the hinge for the float. Take that out and you can pull out the whole float needle assembly. Once you take it out, you will need to replace the o-ring.

[Anonymous]

'86 GS550ES Carbs

Cool Breeze!!! I found it. Now, where can I get the "O" rings? Nice 700 by the way. A friend of mine used to have a red and white one. He's the reason I bought my GS. I also pulled the Pilot screws out and found a broken o-ring as well. Any idea's on a source? Thanks a lot again to all who are helping in my project.

[lhanscom]

Thanks. I bought some o-rings at a hardware store. Just bring the parts down, and look thru what they have, hopefully they'll have something.

[Anonymous]

'86 GS550ES carbs

I forgot to say that I measured the float level very crudely and if I did the measure right, they are way out according to my manual. They should be 20.5mm +- 1mm, and I measured about 15mm. Could they be that far out?