help me revive my 426


5 replies to this topic
  • DirtMongrel

Posted March 20, 2008 - 04:59 AM

#1

My '02 426 has been sitting for about 15-16 months since I got a new bike. I'm getting ready to sell it so I wanted to start it and tune it up, but it wont start. I think I made a huge mistake and drained all the fuel before putting it away. Its getting spark and the carb gets fuel, the pumper is squirting... but the bike only goes brump-brump nothing more. After a while I thought it was getting flooded so I leaned the bike on its side to let fuel out the overfow... nothing comes out? when you remove the little plug on the bottom it pours fuel out though. Fuel is getting to the cylinder, the plug gets wet. I then notice my oil level was increasing and smells like gas.

I really think this is carb related, but don't know what to look for. I've taken the carb out to remove the access covers and the inside looks good and clean with no varnish or dirt. Maybe a seal dried up or something is sticking?

Any clues? This carb is super complicated, alot more then I'm used to. I'd hate to be one of those guy who parts out a bike on flea-Bay just cause I can't get it running. I would sell it non-running as a complete bike, but I'd lose all its value.

Please help... thanks

  • MarshalGiles

Posted March 20, 2008 - 05:35 AM

#2

sounds like your carb float needle was stuck open, allowing the fuel to just flow unchecked into the cylinder and down into the engine. Check that there's not a depression around the float needle. If there is, get another one. It should be near perfectly cone shaped to work properly.
Also, drain and refill your oil. It's no good anymore with gas in it.

EDIT: While your at it, make sure the jets are good and clean. Blow through them with compressed air to get any gunk out. You should be able to see a clear, round hole straight through if it's clean.

  • DirtMongrel

Posted March 20, 2008 - 05:55 AM

#3

Marshal, thanks for the quick reply. I'm aware the oil is no good anymore, but I'd hate to refill and then it happen again during testing. Do you think its OK enough just to see if it starts then when it finally starts refill it. Or will it srew up the starting process or even worse?

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  • yzf426rider

Posted March 20, 2008 - 06:03 AM

#4

i have no idea if it will make it worse but i know i would never try starting it with peti in the oil just incase. not worth the risk when your about to sell it.

  • DirtMongrel

Posted March 20, 2008 - 11:29 AM

#5

sounds like your carb float needle was stuck open, allowing the fuel to just flow unchecked into the cylinder and down into the engine. Check that there's not a depression around the float needle. If there is, get another one. It should be near perfectly cone shaped to work properly.


Ding-Ding-Ding we have a winner :confused:

I assumed when you said float needle you meant the "needle valve" that operates the float... yep thats what it was. Again the rest of the carb was spotless, but that valve was seezed in its seat. It took some soaking and gentle prying to get out. The tip was not grooved but it had oxidation on the sides from the aluminum valve and the brass/copper seat. After a little wd40 and some emery cloth it polished up nice. Works smooth as butter. Bike fired on second kick (after oil change). Now I just have to adjust the throttle cables, I don't remember it being so touchy.

Thanks for the help:thumbsup:

  • grayracer513

Posted March 20, 2008 - 01:08 PM

#6

You might want to find out why the overflowing fuel didn't drain from the carb overflow tube as it should have, while you are looking at it.





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