Leaking carbs, don't know what to do next

[Guest]

The carbs on my 1980 gs550e started leaking last summer and no cleaning/rebuild kits seemed to be fix it. Decided to try to tackle the issue again this season and I'm making it nowhere. I've taking the carbs apart too many times to count already and checked float levels and at the recommendation of a roommate I even tried polishing the float valve needle and seat. Fuel is still seeping down the engine side brass bar holding the carbs together and dripping after a couple seconds of running/trying to start the bike. Any suggestions on where I should go next? I didn't want to separate the carbs, but at this point I'm wondering if there is a crack in one of the carbs.

[LAB3]

I didn't want to separate the carbs, but at this point I'm wondering if there is a crack in one of the carbs.

Sounds like this the only place that hasn't been checked. On my bike there's a rubberised plastic tee that connects the fuel line to the inlets of the carbs. The rubber on the tee deteriorates over time and needs to be replaced, it's about $40 from a dealership. Took the chance on mine last season and being low on cash I wrapped the tee with teflon tape and it got me through. This winter I found some o-rings to put around it and it's dripping just a tad. More than likely I'll pull them again at some point (I too am tired of pulling them!) and give it another wrap with teflon tape.

[cowboyup3371]

During any of the times you have taken the carbs apart, did you properly dip each one and replace all of the o-rings after getting a new set from www.cycleorings.com as well as the bowl gaskets? Have you checked the petcock and make sure it hasn't failed on you?

[Steve]

You also need to be aware that, for the carbs to leak, you need to have TWO failures.

1. Something in the carbs has failed. The usual suspects are the o-ring around the float valve and the o-rings on the transfer tubes between the carbs. Since you said you don't want to separate the rack, I am guessing those have not been replaced. By the way, "rebuild kits" are seldom necessary, and can actually make things worse. The parts included are often of questionable quality. Usually, all that is needed is a set of o-rings from cycleorings.com.

.

2. The petcock is not holding back the fuel properly. First area to address is to make sure you are not leaving it in PRIme position, which is with the handle pointing to the rear. If you are leaving the handle in the RUN or REServe position, you will need to check the diaphragm. First, verify that it does leak. Run two hoses from the petcock to two separate containers. One from the fuel port, one from the vacuum port. If you see fuel in either one, replace the petcock. For some reason, the success rate on a petcock rebuild is only 10-15%.

[bwringer]

It's very common for crud from an old petcock to make its way into the carbs and prop open the needle valves. Petcocks have effective screen filters, but if you move a petcock lever after it's been sitting a few years, you'll send crudniks down directly into the carbs.

If you actually used the janky imitation poo in rebuild kits, I hope you saved the old brass. Imitation needle valves rarely seal correctly, and often the OD and o-rings are incorrect so they leak. The little springs in the fake needles are usually too weak, and the tips are poorly made so they won't match the similarly low-rent needle seats... and on and on. The jets are random scrap, the few o-rings are incomplete and wrong, and so on and so on...

Everything in those kits is hot garbage. Well, sometimes you can use the bowl gaskets... I wish they would stop selling them, or someone would start selling kits worth a damn.