having trouble getting it to fire up

[3scootsforfree]

Hey everyone

I was recently given 3  2004- 2007 Honda metropolitan scooters.  Two I have managed to get going, but am running into some problems with the third one.  

Here's the deal.  I took out the carb and it was toast.  Someone had tried to work it over and had mangled the insides, so I bought a new one.    I have spark, fuel to the carb, and fuel to the spark plug.  I have managed to get it running a couple times, and it even idled for about an hour, and then the temp light came on.  I have plenty of coolant and oil, and the battery is strong, but it still doesn't like to fire.  I am wondering if there is something I am missing here.  I know there are a lot of electrical components in these and am wondering if that could be the cause, or is it a mechanical thing I am missing.  Any help, or suggestions would be helpful.

Thanks

[90GTVert]

Welcome!

Have you done a compression test? Tried to ride it or it has only idled?

[FrankenMech]

Did you adjust the new carb?

[GrumpyUnk]

I would make sure things haven't take up residence in the exhaust system. I would also suggest checking the valve clearance. If you have not done so, I would remove both the main jet, the emulsion tube and the pilot jet. Look through both jets and make sure you can see light. Check the emulsion tube for clogged bleed holes and stuff inside the tube. I would also check that the slide moved freely and the needle did not bind against the emulsion tube when reinstalled.
There is a passage in most for the idle mixture access to the intake/venturi. It is difficult to check for being clogged, but if it is, the idle will be difficult to get adjusted. It is 'behind' the idle mixture screw tapered tip.
tom