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Carb Woes

spyd3rm4n

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Aug 21, 2013
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I bought my blue 2004 FZ1 last year with 2600 miles on it, the bike was stored a long time with 20 year old gasoline doing it's thing to the fuel tank and carbs. I bought a carb rebuild kit and did my thing, doing the RavenRider carb modifications at the same time. I didn't bother replacing the fuel rail o-rings between carbs because there was no leaking, however I replaced the float needles, float needle seats, and bowl o-rings, along with cleaning out the pilot jets which were clogged solid (hence the engine cutting out as soon as I gave it any throttle.)

I did my best to get all the rust out of the tank, and have been riding the bike for the past year quite often, and even changed the fuel filter numerous times since it was still picking up some rusty sediment from the tank. However at one point a few months ago one of the pilot jets got clogged with debris so I had to remove the carbs again to clean it up. All good!

Then I parked the bike and haven't ridden it since October. I just went for a ride and couldn't start the bike, heard the fuel pump prime a LONG time, but then the starter wouldn't turn it over, felt like the engine was locked up. Then I realized maybe I have a cylinder full of gasoline. I waited a moment and hit the starter again, it turned the engine and then fired right up, but now there's gasoline leaking out of the #2 carb, though I can't tell exactly where. I'm thinking a needle valve isn't sealing and filling the cylinder with fuel. The needles and seats are still fresh, so I doubt it's the rubber, maybe just a piece of junk stuck in there.

I'm going to try riding it first, but prepared to pull the carbs again for the third time in just over a year! It's not time for a Tracer 9 yet, I got this.

(Meanwhile my 20 year old Harley that's been sitting in an storage lot and auction lot for who knows how many years before I bought it fired right up on the first attempt; though I had fuel leaks on that too from deteriorated o-rings on the fuel line between the tank and throttle body!)
 
If you suspect cylinder is full of gas, I would check your oil level for overfilling. If gas is in cylinder 2 it has to go somewhere.

The oring in item 18 of this pic is known for leaking and could cause what you are seeing. Did you replace it or everything included in item 18?

Hope this helps.
Jim

fz1 needle seat oring.webpmewhere
 
If you suspect cylinder is full of gas, I would check your oil level for overfilling. If gas is in cylinder 2 it has to go somewhere.

The oring in item 18 of this pic is known for leaking and could cause what you are seeing. Did you replace it or everything included in item 18?

Hope this helps.
Jim

View attachment 35493mewhere
Yessir! That entire #18 assembly was replaced with new crap from the "All Balls" rebuild kit including the o-ring (and #8 and #10 o-rings).

And a lot of that gas from the #2 carb went onto my garage floor, but yeah checking the oil level for sure.
 
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I took a better look at what was going on, fuel still leaking from #2 or maybe the #3 carb. The overflow hoses are split where they attach to the carbs they don't seal and drain the fuel where it should be draining, it's dripping down onto the back of the starter motor. I gave each float bowl a few good taps with the handle of a big screwdriver. Again, when I went to start it was stuck but I could hear the gasoline seeping past the rings s l o w l y until it turned over and fired right up the took it for a very brief ride around the block, less than 30 seconds, to shake things up a bit. So far the leaking seems to have stopped! However my oil is most certainly contaminated with gasoline. Runs great though, just not much more than 1500RPM given the lack of proper lubrication at the moment.
 
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