Starfire GT50 engine fires up but stalls prematurely

Hm I just took a quick look at it and...

The carb seems to be held together by two screws which are face down, making them completely inaccessible except by a specialty 90 degree screwdriver thing..

Are they serious? Just seems retarded.
 
If you have an overly oily fuel mix in the carb, just refill your gas tank with a freshly mixed batch of fuel, mixed at 25-1 for break-in, and do not worry about what is currently in the carburetor. It will get flushed out by the fresh fuel anyways. If you have alot of carbon inside the cylinder and on the sparkplug, you do not need to be worried about carbon inside the carburetor. There really is no way carbon can get inside it.
 
probably just the spark plug -- but

if your tank is dirty
remove fill about 1/4 with cleanning anything with ball bearings
shake and bake turn and twist for a while -- this removes most everyTHING lose

you probable only need to clean up the spark plug

and then

get back on that MB thing and ride
 
Engine running very sporatically

Hey guys,

Still just trying to get my engine running OK.. I've grabbed and mixed some fresh fuel, and managed to get the engine started *once* for a few seconds, but then after literally a few seconds it lost all power and stalled, now I can't get it started again..

Hm.

Any ideas?
 
The first thing I'd check is the spark plug. Try replacing the plug and try starting with a good plug. The Chinese plugs are notoriously poor. If you are getting a strong spark, check the color of the plug after running. Black indicates a too rich fuel condition or a too weak spark, white too lean. A tan or light grey shows your carb is set properly and you are getting good voltage. It is most likely in the spark or carb.
 
hm ok, for a more specific question..

If I take the spark plug out and crank the engine, fuel should come out of the spark plug hole no? or atleast vapor?
 
Some should come out as a vapor. The piston rising in the cylinder pulls a vacuum in the sealed crankcase which pulls the fuel-air mix in through the carb, filling the crankcase with fuel-air mix and lubbing the bottom end. As the piston then goes down the cylinder it creates pressure in the crankcase, which forces the mix from the crankase through the transfer port(s) into the cylinder, very unlike a 4 stroke.

Pull out the plug and put the plug wire back on, then hold (ground) the plug threads against the engine fins away from the plug hole. As you turn over the engine you should see a strong spark in dim light. If the spark is weak it will have a hard time firing the fuel, especially under compression. A fat blue spark with a loud snapping noise is perfect, a fat yellow spark with a fairly loud snapping noise will do, and a weak yellow spark with little snap may not be strong enough. If you are unfamiliar with testing plugs this way, you can do the same test with one plug from your car. That will give you a baseline for what a hot spark should look and sound like. You may get a nice jolt doing this so hold the plug with a pair of pliars with insulated handles.

There are some threads here with names and numbers of better quality spark plugs for your engine. Luck!
 
Which position is the choke lever in, up or down?
(You might have the choke on.)
Down=off, up=on.
Try one starting attempt for a few yards with the choke on, (engine will pop), then a second try with the choke off.

Regarding spark plugs, toss the stock ones and buy NGK B6HS for reliability. Or the slightly hotter B5HS.

Also, if I were you I'd add an inline fuel filter, too. These tanks are full of ****.

... Steve
 
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heh yeah I know, I mentioned in a previous post that I noticed a lot of sediment in my fuel line and had to drain it and rinse my tank out.

I'm using an NGK Spark plug of some variety (came with two in the kit), im having a lot of trouble testing them however as its **** impossible to crank the wheel and hold a spark plug.. Or ride and hold a spark plug attached to a tiny cable.

The fact that nothing seems to come out at all when I crank it with no plug in indicate to me that its the carby, however the **** thing is screwed on with the screws upside down for absolutely no reason, making them inaccessible except with a right angle screwdriver thing. So incredibly dumb. Good old chinese engineers.

There might be some vapour comming out though, its hard to tell without literally sticking a nostril to the plug hole.. which seems like a bad idea.

I've tried it in every possible choke combination to no avail. Also unsure as to which way the little white thing is supposed to face (up or sideways) so ive had to try everything twice..... Nothing mentioned in the manual about this at all.

Sigh. After nearly 2 months working on it, I just want to have one decent freaking ride. :(
 
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