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97' YZF600R Leaking Unspent Fuel Issue - Advice please!

6K views 3 replies 4 participants last post by  itsmygame 
#1 ·
Hi all, I'm Scott a new forum member who has owned the above bike for the last year+, and I'm in need of some advice on a problem. Here's the situation:

The bike was stored for several months over the winter season here in Wisconsin. I pulled the battery, left just a little fuel in the system and put a little stabil in there. I was told in hindsight that I should have left a full tank and I might have used too much stabil, but that's what I did and now I'm moving forward. Taking her out of storage just recently, I filled up the tank with premium she she starts really hard. The throttle and choke have to be played with the entire time or she will die, and after about 30 seconds of running, unspent fuel will begin to leak out the seam where the exhaust pipe fits into the long exhaust piping that comes out of the manifold (aka way back by the footpegs not anywhere near the engine).

So first thought is that combustion is not happening in 1+ of the cylinders, causing the engine to run like crap. The unspend fuel is just going completely through the unfiring cylinder(s) and gets shot out with the exhaust fumes, builds up in the vertically angled exhaust pipe, pools up inside and leaks out at the seam into a puddle on the ground.

We checked the spark plugs, dirty but not seemingly fouled so we put them back in and moved out. Yanked the fuel tank and air box, took a basic look at the carbs. All of the butterfly valves seem to open close fine when we play with the throttle, couldn't see anything else weird but we have not done any disassembly of the carbs (yet). Never done anything like that before (but we have some basic experience and a haynes manual to help) so maybe we will.

Here is the twist that I'm hoping might make the light bulb turn on for someone reading this: When we drained the carbs, we got about 3/4 dixie cup full of fuel from all of the carbs, except the far right one, which was COMPLETELY dry, not a drop to her. Someone suggested the float might be stuck, do you agree? What else could it be? I don't know engines through and through, but it baffles me that fuel could go through the carb, through the engine, not detonate, build up in the exhaust pipe and pool on the ground and that absolutely none of that uncombusted fuel residually ends up sitting in the carb to be drained when I loosen that drain screw.

Any advice would be great, trying to avoid taking it to a shop, finances are tight.

Thanks,
Scott
 
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#4 ·
Yes, you will have to clean out the carbs. Just a little bit will gum and clog. Do not over tighten the jet or they will snap. Just brass. Clean jets w/ a file or drill bit (w/o drill) start very small. I use weld tip cleaners, can get at home depot. Next year dump unsed fuel into car and run bike till it stops. It is the safe way for storage.
 
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