Need help from carb experts. 2t 250 | GTAMotorcycle.com

Need help from carb experts. 2t 250

SVeezy

Well-known member
New to me 2000 yz250, it was running fine a few months ago but wasn’t getting spark recently. I cleaned the plug cap and now getting a spark but the carb is pissing fuel out the drain tube. I suspect there is a float stuck but really don’t have any knowledge of carbs.


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Robbo

Well-known member
New to me 2000 yz250, it was running fine a few months ago but wasn’t getting spark recently. I cleaned the plug cap and now getting a spark but the carb is pissing fuel out the drain tube. I suspect there is a float stuck but really don’t have any knowledge of carbs.


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Try tapping the carb body/bowl with a rubber mallet or the handle of a screwdriver. If it’s a stuck float, this will usually do the trick.


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SVeezy

Well-known member
I actually did give it some taps with a wrench, it seemed to help but not solve the issue


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Robbo

Well-known member
Next would be drain the carb and remove the carb bowl and check the float movement. Also, check the float’s condition for cracks. Hopefully you can do this without removing the carb from the bike.


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boyoboy

Well-known member
^ whats said above and then..

lay bike on left side, then lay down on right side - and then look / see again if fuel stopped coming out the overflow. or not.

pretty easy to remove the carb on a 2 stroke single. look/see - sometimes the float valve and seat are old and not sealing - replace seat and float valve as a set.

best luck. watch vids; find a friend w some carb experience. get assistance first time into a carb.
 

SVeezy

Well-known member
Thanks gents. This is exactly the advice I was looking for. I’ll dig in and report back.

Cheers


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SVeezy

Well-known member
Just a quick update. I managed to blow some air through the lines and that stopped the overflow leak. I’ll likely have to clean the carb up soon.

There is spark but it doesn’t look as strong as I’d expect. I’m going to have to dig up some testing details on the coil and work from there.

This is taking way longer than it should but it’s a back burner project at the moment


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Robbo

Well-known member
Just a quick update. I managed to blow some air through the lines and that stopped the overflow leak. I’ll likely have to clean the carb up soon.

There is spark but it doesn’t look as strong as I’d expect. I’m going to have to dig up some testing details on the coil and work from there.

This is taking way longer than it should but it’s a back burner project at the moment


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Maybe check resistance in the plug cap and also that the cap and wire have a strong clean connection.

Also, check the spark plug gap is within spec for your bike.


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SVeezy

Well-known member
Cleaned the cap and have a new one on order just in case, I figure it’s cheap insurance. Cleaned up the connection to the wire as well.

I bought a new plug at the start of the issues so that’s covered. Gapped it too.


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SVeezy

Well-known member
I should check the resistance on the cap, I think 15ohms is common but will have to look it up


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