kentaledge Posted August 27, 2011 Report Share Posted August 27, 2011 Hi all Had a problem the other day bike was running like a dog. Messed about with fuel air mix, then the floats stuck open causing fuel to leak from air air filter. Stripped carb down, blew/cleaned everything out . Now fuel is very slow getting into float chamber, bike starts after 5 mins stood idle, will tick over , rev a little, say 1000 rpm any thing above that just dies, fuel filter is clean, although very bubbly when running carb jets chamber everything is fine, sprayed ethanol into air intake and bike revs out fine(not the best idea by the way but ok for a tester) Any ideas has me head wrecked Andy Quote Link to comment Share on other sites More sharing options...
jordi Posted August 27, 2011 Report Share Posted August 27, 2011 Hi all Had a problem the other day bike was running like a dog. Messed about with fuel air mix, then the floats stuck open causing fuel to leak from air air filter. Stripped carb down, blew/cleaned everything out . Now fuel is very slow getting into float chamber, bike starts after 5 mins stood idle, will tick over , rev a little, say 1000 rpm any thing above that just dies, fuel filter is clean, although very bubbly when running carb jets chamber everything is fine, sprayed ethanol into air intake and bike revs out fine(not the best idea by the way but ok for a tester) Any ideas has me head wrecked Andy Check the fuel tap, maybe the filter is blocked or possibly the small drilling through the tap has something in it. This will cause the problem you describe. You will possibly need to remove the tap from the tank to make sure all is clear. Quote Link to comment Share on other sites More sharing options...
kentaledge Posted August 27, 2011 Author Report Share Posted August 27, 2011 Check the fuel tap, maybe the filter is blocked or possibly the small drilling through the tap has something in it. This will cause the problem you describe. You will possibly need to remove the tap from the tank to make sure all is clear. Done all that Jordi it's more to do in the float chamber mate cheers for the reply Quote Link to comment Share on other sites More sharing options...
charliechitlins Posted August 28, 2011 Report Share Posted August 28, 2011 As always...check the last thing you messed with. Take the float bowl off and see if everything is right. But you didn't need me to tell you that. Quote Link to comment Share on other sites More sharing options...
jse Posted August 29, 2011 Report Share Posted August 29, 2011 As always...check the last thing you messed with. Take the float bowl off and see if everything is right. But you didn't need me to tell you that. Be sure you take the carb completely apart, not just blow things out, especially the float needle assembly. Sounds like something to do with the main jet as it dies just about the time the carb starts to draw from the main/needle jet system, although you said you cleaned that all out. Also look for any binding of the floats movement in the bowl. Jon Quote Link to comment Share on other sites More sharing options...
exvet Posted August 29, 2011 Report Share Posted August 29, 2011 Make sure you didn't put the floats in upside down. As already, posted check the last thing you did. good luck Quote Link to comment Share on other sites More sharing options...
kentaledge Posted August 31, 2011 Author Report Share Posted August 31, 2011 Have done all of the below, came home yesterday, i had left the fuel tap on, and the carb had flooded its self and drained the tank all over the garage , put a small bit of juice in to see if she would go, guess what, nope still the same, im going to take it completely to bits again, the floats look brand new and slide up and down the pins flawlessly , ill post when i find the problem, thanks all for your advice, Andy Quote Link to comment Share on other sites More sharing options...
kentaledge Posted September 1, 2011 Author Report Share Posted September 1, 2011 Right lads, it is not the carb, the only other thing i have done is replaced the O rings in the exhaust were the stainless pipe from the cylinder meets the exspansion chamber/baffle, could lack of back presure be causing it to draw in more air, 1 of the O rings failed and it is losing waste gas from this connection Still ticks over as soon as you apply a small bit of throttle cuts out, the carb floats everything are fine, honest even cleaned the small jet holes with a strand of copper wire Im stuck Andy Quote Link to comment Share on other sites More sharing options...
charliechitlins Posted September 2, 2011 Report Share Posted September 2, 2011 If the float was fine, it would have closed the needle valve and there wouldn't be fuel everywhere. If your piston was a little down, the lower end of the engine could be full of gas, too. Make sure the float is working properly AND the float needle is working properly. Also...shake the floats to see if one is full of fuel. Quote Link to comment Share on other sites More sharing options...
kentaledge Posted September 16, 2011 Author Report Share Posted September 16, 2011 If the float was fine, it would have closed the needle valve and there wouldn't be fuel everywhere. If your piston was a little down, the lower end of the engine could be full of gas, too. Make sure the float is working properly AND the float needle is working properly. Also...shake the floats to see if one is full of fuel. After much tinkering, a mechanic looking at the bike, and a lad in the local garage who has loads a bikes looking at it, we are all at a loss, buy a new carb i what the answer off all a them is, There is nowt in the floats, sometimes it lets fuel into the float chamber, sum times, and sumtimes it does'nt, it a complete mystery, it has ran like this since i changed the slave seals in the slave cylinder,it ran fine then except ATF fluid leaked out as i found that the previous owner had threaded 2 bolts in the crank casing and the polish lad in the local garage re-tapped these for me , since then its ran on tick over ok, slight rev say to 1k, dies, as i say before the crank case bolt were re-tapped, it was fine. But this still does not answer the float chamber flooding, or getting no fuel, everything from putting the fuel in the tank , to it going into it combustion chamber has been checked, checked again, and double checked, by me and 3 other people. I am now thinking about making a short film of a gas gas 250 pro flying off the quarry cliffs on fire and putting it on you tube Any suggestions Quote Link to comment Share on other sites More sharing options...
kentaledge Posted September 17, 2011 Author Report Share Posted September 17, 2011 Be sure you take the carb completely apart, not just blow things out, especially the float needle assembly. Sounds like something to do with the main jet as it dies just about the time the carb starts to draw from the main/needle jet system, although you said you cleaned that all out. Also look for any binding of the floats movement in the bowl. Jon Quote Link to comment Share on other sites More sharing options...
kentaledge Posted September 17, 2011 Author Report Share Posted September 17, 2011 Jon could you read rest of my bloggs mate Quote Link to comment Share on other sites More sharing options...
jse Posted September 18, 2011 Report Share Posted September 18, 2011 Jon could you read rest of my bloggs mate Andy, I'm guessing that there may be some binding in the movement of the arms the floats ride on. Sometimes the head of the float needle does not move smoothly on the tab on the float arms. There are only a few components on the fuel level regulation assembly: the floats, the float arm/pin, the thin rods the floats ride on and the needle valve assembly. Unlike the fuel delivery system that has a lot of disimiliar components that overlap in operation, the float level system is essentially digital and is on or off, so it could be something simple like a rough spot or manufacturing burr that is hanging things up. Jon Quote Link to comment Share on other sites More sharing options...
bergerhag Posted September 18, 2011 Report Share Posted September 18, 2011 I had a problem like this on a Husqvarna enduro. it behaved just like this, it had a Dell'orto carb. Anyway, the problem turned out to be very very small pieces of grit in the fuel tank, small enough to pass the filter screens but big enough to get the float needle stuck. I cleaned out the tank and installed an extra fuel filter, never had a problem after that. Quote Link to comment Share on other sites More sharing options...
kentaledge Posted September 18, 2011 Author Report Share Posted September 18, 2011 Andy, I'm guessing that there may be some binding in the movement of the arms the floats ride on. Sometimes the head of the float needle does not move smoothly on the tab on the float arms. There are only a few components on the fuel level regulation assembly: the floats, the float arm/pin, the thin rods the floats ride on and the needle valve assembly. Unlike the fuel delivery system that has a lot of disimiliar components that overlap in operation, the float level system is essentially digital and is on or off, so it could be something simple like a rough spot or manufacturing burr that is hanging things up. Jon I'll have a closer look at that then Jon, myself and the other lads were looking at the usual suspects , but it was fine before maybe just maybe it's summer like that, heads wrecked Quote Link to comment Share on other sites More sharing options...
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