Carby Question regarding fuel to carb



I recently purchased a 49cc ebay engine and installed it on my Schwinn SS cruiser. I am having this problem: The fuel doesn't seem to be decending down my fuel line in large enough volumes to fuel the carb, the result is that the bike runs great for a couple of hundred yards-and then dies out.

I don't know what normal flow from the tank looks like in a clear fuel line, but it doesn't seem to be doing anything but trickling minimally.

I pulled the stock filter out of the petcock, like everybody says to do. I then replaced it with an inline filter. I've even taken the needle valve off. I read that there is a filter in there too-but I couldn't seem to locate it. There was a pointed rod sticking up toward the needle valve, but I couldn't get a good grip on it to try and remove it.

If somebody can shed some light on this issue for me I'd greatly appreciate it.


This bugged me too but try pushing the tickle plunger down three or four times,my fuel line is clear and sometimes mine just shows a couple inches of fuel at the bottom but i never run out hold the plunger down till gas runs out the carb,the gas trickles down the sides of the fuel line and it doesen't seem like enough but I never run out. Of course now I have other problems spark mainly.

Did you ever look inside your kit's tank before you put fuel in it? Some of the tanks are pretty rusty inside and there may be a flake partially blocking the already-small orifice diameter of the kit's fuel valve; something too big to even make it to the inline filter.

I had this problem, but it wasn't a rust chunk; it was a piece of the plastic that the tank's fuel cap was wrapped in. Granted, there's not a tremendous amount of fuel flow even when there's nothing in the way... but because it's a gravity-feed system, the optimim flow rate may lie within a very narrow range so as to keep the carb bowl filled but not overcome the float's needle and seat.
Take your fuel line off the carby and put it in a clean glass jar.Turn on your petrol(gas) and see what happens...see if it flows consistantly.
These HT engines use very little fuel so it's hand to tell if their working properly on the bike.
Also make sure your fuel line is not kinked or at any wierd angles...Chinese hose and not very good quality.
With ANYTHING like this u start with the basics and work foreward going from simple to complex solutions.
Lots of good thoughts... I was wondering if the problem might lie in the tank. I didn't swish a bit of gas and dump it before initially filling the tank. Live and learn! I will try these suggestions. Thanks.
Just had an original thought. (happens occasionally) How level is your carb? If they are too far from level, it affects the fuel level.

Just had an original thought. (happens occasionally) How level is your carb? If they are too far from level, it affects the fuel level.


It affects fuel level in the carby bowl but it doesn't seem to affect engine performance.I've seen engines(hence carby's) at radiculous angles and they perform normally...........constructive thinking though. :)

PS....i criticize these little HT engines sometimes BUT i have enormous respect for them...their VERY versatile & forgiving.
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I appreciate all of the helpful feedback and suggestions. I removed the petcock again and blew it out. I then road tested it and it ran great and had more fuel in the fuel line. I think my problem is solved! I can't wait to go for my first ride (Other than down my street) this weekend. My brother and I have a 5 mile plus ride planned weather permitting. It has rained here for the past 2+ weeks!