Leaking Carburetor

[badbmwbrad]

[size=14]I purchased a 1983 R65LS on Columbus Day last year.  It had <5K miles and had been stored in a heated garage for 28 years.  There was no fuel in the carburetors but a small amount of stale fuel was found in the tank.

At that time, I cleaned some varnish out of the carbs, added fresh fuel to the tank and got the engine running very well.  I then added fuel stabilizer to the tank and ran the engine to circulate stabilizer in the fuel delivery lines and float bowls.  

I closed the petcocks and placed the bike in storage for the past year.  Last weekend, I brought it out of storage to start the engine.  After much effort I was able to get it to run with the engine partially choked but it wouldn't run with no choke.  

In addition, the left float bowl drips fuel continuously.  I did remove the left bowl and observed the fuel flow shuts off when I raise the float with my hand.  

The carb's floats appear to be made of white-colored styrofoam material.  They're not especially discolored nor was there any varnish observed in either float bowl.  The right carburetor does not drip any fuel.

Any helpful suggestions regarding what might have happened within the left carburetor during the past year of storage is appreciated. [/size]

[Bob_Roller]

Best guess would be, that the carbs need to be 'freshened up' , new rubber parts, gaskets, floats, float needle valves, as the bike is 29 years old .

All the passageways in the carbs new to be cleaned with carb cleaner to assure that they are not restricted .

Also on the carb bowl, there is a small reservoir in one corner, at the bottom is a small hole in a brass fitting, not uncommon to have this get clogged and the bike won't idle because of it .

Also, I would get rid of the old fuel, I let a bike sit for about a year with a full fuel tank with stabilizer and the fuel was pretty much no good anymore .

I'd remove the fuel tap from the fuel tank try to get all of the old fuel out, check the condition of the filter screen that goes over the fuel tap inlet tubes .

Replacing the fuel lines would probably be a good idea, they are most likely original, 29 years old .

These bikes need a bit of care after being idle for a few decades, once you get them back into shape, they will run for a long time, they are not high tech finicky machines .

My '82 LS started doing this about 2 months ago, parked it until my vacation (now), rebuild kit should be here Monday or Tuesday of next week .

I'm doing a complete rebuild, so I don't have to do this for another 20 years !!!!!

[tvrla]

With white floats (they turn yellow and then brown with age), I can't imagine the carbs being in too bad a shape, especially with such low mileage. But like Rob says, the stabilizer may not have helped much.

But there's no reason to get a complete rebuild kit! At the most I'd imagagine needing jet 0-rings. Possibly. Jets don't wear out - except the needle jet (and the needle) but that won't be for another 40K at least.

A lot of times a little bit of gunk sticks to the float needle and allows a little trickle of gas through, which then overflows.

Clean up what you can and ride it - that may be all it needs. If it continues to be a problem, then go into it deeper.

[Session101]

i would make sure the bike is on the center stand, and just double check that both carbs are centered upright, i used a level on the flat side of the carbs, then i would make sure to adjust the float height properly. Be sure to check your float bowl gaskets, they are cork and should not be brittle.

I would either dump alcohol in your lines and let that run to the carbs to make sure there is no water or bad fuel left over, then run the bike.

 If that doesn't fix your problem, then it time to do a quick rebuild, and its quick, just replacing gaskets and making sure the carb parts are clean.

[Barry]

That's a nice find Brad. Mine had 6200 miles at 28 years old.

I did strip the carbs and replace O rings. Diaphragms and floats were fine. I removed the carbs but with care you can do quite a lot without taking them off the bike. With the float bowl off you can remove the main jet and then the main jet holder (take care if it's seized and renew the O ring). The needle jet and emulsion tube will then drop out. These carbs can accumulate some crude around the emulsion tube so it's worth looking up inside the carb boss to check it's clean.
The pilot jet just screws out and will usually need a new O ring. There are some very small bypass holes just down stream of throttle plate which will affect the off idle response and they are worth checking for blockage. The choke or more properly called the enricher may need new gaskets and O rings and that's about it.

These carbs are easy enough to work on and once they are properly clean and set up it takes no time at all to keep them that way

This is quite a good description of a carb rebuild.

http://www.gunsmoke.com/motorcycling/r100gs/carb_rebuild/index.html