fuel or carb problem? help

hi guys listen I installed an arisal kit and 15mm delorto carb on my tomos bullet(yes, it really does fit and everything is hooked up right) now I have spark and the moped started for a minute but I think it was the starter fluid I put in there. I have fuel coming through the fueal valve and down the tube into the carb. I don't know if it's going through the carb but I should imagine it is. I was wondering if cause a number 68 jet is in there it might be flooding it if not that I put the original exhaust back on which I'm not sure is open enough for this kit what do you guys think it should

Re: fuel or carb problem? help

Pull the plug after a failure to start. Check n see if the plug tip is soaking wet. If it's dry and Starter Fluid gets the engine running, ignition is ok but the carb is not delivering fuel. If it's wet it could be flooding or spark/ignition could be weak.

Is that carb new or old and was it cleaned? If there's a float bowl drain open it and observe fuel gets into the bowl (or not).

Jet size is pretty much out of the picture at low speeds.. float level would have a greater effect and if it's high can cause flooding at any throttle opening... low float level can cause no or insufficient fuel delivery.

There's a whole bunch of things that could be wrong. Approach the problem systematically and resist 'imagining' that fuel is being delivered. Nobody else knows the particulars of what you did and are doing so provide more details and information if you want more accurate diagnostic ideas.

Re: fuel or carb problem? help

Is this an A-3 with a modified connecting rod?

Re: fuel or carb problem? help

yes this is an a3 with a modified connecting rod and I take back what I said just went out and kicked it over started first kick and kept going but sounded like it wanted to die when I let go of the throttle. at full throttle the back tire looked like it was spinning enough to generate 5mph maybe. after about 30 seconds of running the cylinder was hot enough to seriously burn you if you kept your hand on it for a couple seconds. there was what felt like hot air coming out of the exhaust but no smoke or nothing....anyone have anyclue as to what the hell all this might mean I kinda thought that a hot cylinder meant it was too lean or too rich or something but I don't remember. anyone any ideas

Re: fuel or carb problem? help

should we assume you are adding 2-stroke oil to the fuel or that some automatic oil injection system is working?

symptoms of what's happening is nice but more details of exactly what you have there would be nicer.

Re: fuel or carb problem? help

no I have to premix I added aproxiamately 3 ounces to one gallon of gas cause I heard with the airsal you need to have a tiny bit more oil than 50:1

Re: fuel or carb problem? help

pull the head and cylinder off and examine the piston and the cylinder surface. Any shiny spots on the piston? Any marks on the cylinder bore?

Re: fuel or carb problem? help

what would that mean? I wouldn't think that would have anything to do with it but...I don't know...hmm it just seems odd it should run perfect...oh did I mention I'm at 7000 ft in elevation I forgot about that too...thats another reason I figured it has to be something with the jetting jetting at this elevation in regular car carburetors has to be chaged....how can you tell if your moped is running rich or lean? and could it have something to do with timing or something of the sort? would a cdi coil fix that?

Re: fuel or carb problem? help

_at full throttle the back tire looked like it was spinning enough to generate 5mph maybe. after about 30 seconds of running the cylinder was hot enough to seriously burn_

you seem to be saying the thing gets too hot after 30 seconds of an estimated 5mph speed/ rpm on the center stand... I'm guessing there's a ton of friction causing the heat and the 5mph top speed limit..

Yes, it should be running perfect but evidently it aint.

Re: fuel or carb problem? help

high elevation means rarified air.. slightly less air and less oxygen. This would promote a rich mixture. A rich mix has a cooling effect by both slowing combustion speed and by providing extra fuel which evaporates and cools the head and cylinder.

Cold temperatures would make the air dense and do the opposite.. high elevation and cold tampertures sorta evens it out a little.

If you have a legitimate reason to suspect the carb is way out of tune, say why. Guessing about fuel mix and timing is not the way to go about finding the problem. Same goes for ignition timing.

You can't do plug chops (spark plug condidtion says a bunch about fuel mix) till its running halfway decent.. but plug chops will not tell you what's happening at near 5 mph.

Timing could be way off but you are there and can check that and eliminate that as a possibility.

Re: fuel or carb problem? help

ok went back for a second look to make sure that before I dissassmbled everything that it wasn't the exhaust. so I took off the pipe and started it and the tire looked more like it was spinnging 40mph now alot better. but the moped is really load and makes alot of popping sounds I'm not sure if thats cause without the pipe you get to hear all the explosive action or what. but does it sound like maybe my old exhaust pipe was clogged or something? I know it has alot of carbon build up and it's pretty thick just on the part where you hook it up to the cylinder...do you still think I should look for shiny spots or wait for my new exhaust I was ordering and see what that does first?

Re: fuel or carb problem? help

oh wait I forgot, I ran it for a couple minutes with the pipe off and the cylinder and head didn't get very hot at all they were more like mildly warm...I have a feeling the pipe was clogged and the exhaust wasn't able to escape....but I dunno

Re: fuel or carb problem? help

and yet again I'm back after further testing I realize the noise waws just because it was in my garage and it echoes LOL I took it out side and rode it around and it sounds totally normal and did close to 40 without the exhaust pipe on...which is unusual because on a two stroke a pipe makes them go faster so I think I'm jusat gonna wait for my new pipe and see whats going on but thanks for the help guys

Re: fuel or carb problem? help

oh and one more thing I'd like to add this time after running it about 20 minutes at full throttle the sylinder and head still wren't real hot I had my hand on it for about 15 seconds before it kind of started to burn so thats probably about normal I would imagine right?

Re: fuel or carb problem? help

Make sure you run it with an exhaust pipe. You MAY hurt that cyl. or piston without one.don-ohio

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