Can't get it running everytime

[marc]

Hi everyone I got my first gas scooter it's a 49cc qingqi qm50qt Chinese model and I'm having some trouble with it, I got it used and not running for a long time, cleaned both tanks, fuel and oil lines with new fluid, cleaned carb throught, checked everything over and I just can't get it running it's started before when I put gas in the carb, usually starts after it's been sitting for a while and last night my dad put his hand on the air box side of the carb for the choke and it started and ran so I looked into the choke and it wasn't getting any power to the plug so I swiched it to this other plug there that was getting 12v and still no luck and tried the hand thing again and nothing, looking for suggestions on where to go next and how to test/fix the electric choke if that's the problem, Thanks

[islandscrub]

(newb shot from the hip answer) Maybe you have a leak in the engine chamber somewhere. Cylinder gaskets, intake gasket, crank seals, case half seam. Try a leakdown test if that's within your capability.

[marc]

It's looking like I might have to do that, I checked the choke this morning and it was working, the only other thing I can think of other than doing the pressure test which I can probably do myself although it'll be hard to get to everywhere around the engine with it being so cramped is the hose that goes from the carb to the air box is in bad shape, cracked when you squeeze it and has a couple holes, would that be enough to make it not run? I have tried starting it without the hose and airbox but i hear that gives it too much air like a pod filter I'm going to try sealing the crap out of that tonight and see if it does anything I'd like to just replace it but I can't find the part and I don't really want to go to a pod filter either.

[islandscrub]

You can try that first, sure. I found a small diameter replacement shop vac hose at the hardware store for about $14 and used that on my airbox. I couldn't tell you exactly what diameter it is, but it fits tightly over the stock carb intake. Works great with some adhesive to seal the connection on the airbox side. It's also super long so I can chop out as many pieces as I'd like from it in the future.

[marc]

Yeah I've thought about that however it goes inside the box itself so it is bigger on both sides then smaller where it fits into the box so I'd need the factory piece probably

[90GTVert]

The hose will be a problem and needs to be dealt with. Just for getting it started though, you should be able to take the airbox completely off and still get it fired up. Cover the mouth of the carb and see what happens. It should get some fuel on whatever you're using to cover it after you've cranked it. If not, it may not be picking up fuel. You could try putting drops of gasoline into the cylinder through the plug hole or I usually just use an unlit propane torch kinda in the carb (or airbox if it's sealed) and see if that will get it fired up. If so, it is having trouble with fuel delivery.

[marc]

I put some rtv silicone over the hose so it should be fine now, my dad did put his hand over the carb and got it to run and idle for a little bit but then it died that was the best it's gotten, it did get some fuel there when I tried it. My next step is I'm going to take the engine right out and do a pressure test as I'm not sure what else to try really I will also be putting some gasket maker in replace of the exhaust gasket when I put it back together as it wasn't looking great as well.

[geoffh]

If your taking the engine out go the whole hog check and reseal the reed block,de carb the head and piston,clean the carb out,fix that air box,it sounds a lot of work but won,t take more than a morning.You have to replace the exhaust gasket no amount a sealer, gasket stuff will do it right, 3 types any one will do I prefer the metal ring  shown at the top of my display plinth