I was out today on my txt pro 300, not had it out for 3 week, it started fine, then started to cut out, it would slowly die and flood, it would start up and be fine then do it again. I took the carb off (with the limited tools I had) everything looked fine, put it all back and put in a new plug. Fired straight up and did it again. Any ideas lads?

Bloke at a trial had the same problem last week. It turned out he`d put too much oil in his fuel. His bike was brand new !

Possibly a blocked main jet.... If it were me I'd be taking the carb off and stripping it down and blast the jets and all other little holes with compressed air or carb cleaner.

Do all the jets screw in tight or are any set at certain turns out or anything? I just took Carb off in car park today but didn't touch jets

How do you know it is flooding? - is fuel running out of the carb overflows - if so its probably dirt or water in the float controlled valve.

Cheers

Everything I took the plug out it was soaking wet with fuel

Wet plug can come from either excessive fuel or no spark. Here is what I would check:

1) Remove plug, clean, connect to wire, hold plug against head and kick the start lever to see if you have strong spark. If yes, install plug.

2) Remove the air filter. Start bike and see how it runs - especially at speed. I had an old foam filter that simply plugged up and flooded the engine

3) Remove the carb, disassemble and clean all passages with good carb cleaner then blow out with air line from both directions. Be sure to count the turns on your idle and air screws before you remove them.

Hope this helps.

Edited October 1, 201213 yr by thats_a_five

This is the first time I've run it since I fit a new Jitsie air filter, all I did is swap the filters, should I of made some adjustments too?

Lee,

If the old filter was not maintained, and was super dirty, and someone adjusted the carb for this condition, then "maybe" you would have to re adjust? otherwise not.

bad gas, can cause problems, gas goes bad in smaller quantities faster than big oil storage farms. so you could have now, a carb that is clogged up, the jets are about the sizes of pencil lead for mechanical type pencils, if you get what I mean. Just a short story, I took apart a 2stroke carb from a wetbike (jjetski like thing with Suzuki outboard motor)... cleaned the carb, and while putting it back together a bug, a gnat to be exact, crawled into the fuel inlet area. this plugged the main jet, after about 30 ft of running.

But, otherwise, even if everything "is adjusted wrong" on the outside of the carb, I think you should be able to start the engine, it might not idle and it might run like $hit, but if it is getting the 3 parts of any fire, fuel, air, ignition (spark) it should attempt to run.

you can (although risky) squirt a little gasoline into a carb, I use a short squirt of starting fluid when working on old junk bikes, just to hear it run for a hlaf a second... Beware, there is NOT ANY LUBRICATION in starting fluid, so only use it once or twice before getting premixed fuel into the engine, IMHO>

after that, if it runs then you have carb problem probably. BTW, haven't tried this on anything newer than say a 1995 or older bike, since anything that new usually runs when I get it...

If it has stopped running abrubtly (doesnt sound like carb problem, unless for some reason float stuck open) you have most likely, an electrical issue. it can be as simple as the kill switch is stuck grounding out the spark, to bad electronics under the tank.

Kehins like 1.5 turns out on the idle mixture screw (this screw is usually in a hole, so to speak), Delorto you start with 3-3.5 turns out. then adjust to suit the engine.

The bigger and more exposed screw should be idle speed/tickover, the screw raises and lowers where the slide stops when you let off the throttle.

Edited October 2, 201213 yr by sting32

Thanks for the replies,

It didn't just Stop dead, it sort of bogged out, like it tried to rev but No noise. I took the Carb to bits today and found the o ring the sits on the jet that sits in the float bowl trapped, I replaced it and rebuilt it, it seemed OK but I didn't have much time to try, Ill let you know tomorrow, fingers crossed

Still same??? And now I think my water pump seal has gone, coolant emulsified and gear oil looks a bit milky, is there anything else it could be? Could this cause the flooding?

Milky oil is most definitely water in the oil I just had the same problem. I would suggest a waterpump seal kit and a new set of O rings for the head.

Also check your fan is working as overheating could of been the cause of the seal failing, It was the cause of mine.

As for the "bogging" it still sounds fuel related unless he head O rings are so knackered there's no compression left....

Sort out the O rings and water seal and see if there's any improvement and make sure the fan is working!

Just out of interest, what type spark plug is in it?

GJ

I put a head spacer in, it's been fine since then, maybe I trapped the o rings? The cooling fan is working fine, I put a new jitsie air filter in- straight swap surely? I noticed the pipe that goes from one side of the Carb round to the other side had a big hole in it so I swapped it. Ever since that it's flooded? I've got a new NGK plug in it

I would still be tempted to replace that water pump seal mate. If its failed to the point of letting oil into the water that would say to me it's definitely had its day. If the water was emulsified with oil that is! The water is under pressure so I can understand it forcing its way into the gearbox but for oil to come back into the water.....

Better safe than sorry!

Just a thought.... Maybe the fuel filter in the tap or the one on the side of the carb (if it has one) could be clogged up with crap? Long shot but might be worth a check.