POS tempermental greyhound engine

[Bluethunder3320]

sold this go kart to a friend a while back. it only worked for a couple days then it quit running. so i picked it up today and told him i would do my best to get it running again

then i found out a kid who calls himself a "mechanic" took the carb apart and put just about every single piece in backwards that could go backwards.

got everything back the way it goes, it started up on the first pull and ran great.

then i brought it to him... it ran great for about 20 minutes then started acting like it was on choke. i tried taking off the air filter and it didnt make a difference.

then i scraped the silicone gasket off, where the carb meets the air filter. it started up and ran great. we filled it up with gas.

then i got on the back of it and we were pulling wheelies... then all of a sudden the engine lost power and quit. it would not restart no matter what we did.

we pulled the cord for like an hour straight trying different spark plugs, dumping fuel into the intake, changed the oil.

the engine would start but not start. it was so teasing. it ran at very low rpm for 5 seconds at a time.

we have SPARK, COMPRESSION, FUEL. what else? this one has me totally stumped

 

[r97]

Air leak? Valve lash? Spark timing? Partially clogged fuel line/circuit?

 

[Russ2251]

Silicone gasket???
Why???

3 things are needed for an engine to run properly.
Can you not figure it out?

If we were not here...what would you do?

Use what was given to you!!!

 

[Bluethunder3320]

it must have something to do with timing. because it acts like it has an advanced flywheel key.... i dont understand how it suddenly choked out and died then wouldnt restart. it was running great.

 

[Bluethunder3320]

Silicone gasket???
Why???

3 things are needed for an engine to run properly.
Can you not figure it out?

If we were not here...what would you do?

had nothing else to use. and i was too lazy to cut apart a cereal box. its only for the gasket that connects the carb to the air filter housing. not a crucial area. ill probably make a paper gasket anyways

air/fuel, compression, and spark is there...

if diy go karts didnt exist... well then i guess my life would be harder

 

[souperman000]

did the carb have any junk in it that might have gotten sucked into the engine? I also think it might be valves.

 

[Russ2251]

air/fuel, compression, and spark is there

Obviously one of them is missing. Recheck all.
http://www.thebriton.com/three.htm

http://auto.howstuffworks.com/engine3.htm

http://www.dansmc.com/basics1.htm

 

[OzFab]

Is it possible a piece of the silicone got sucked into the carb & blocked something?

 

[Iron John]

Do you have fuel coming out of the fuel hose where it attaches to the carb?

Is the float/needle stuck closed?

Valves/ignition/everything else is OK because it runs when you prime it. Must be fuel not getting into the carb or some crap that got washed downstream and plugged up a jet.

 

[gixxerkart]

Suck. Squish. Bang. Blow. You need FOUR things for an engine to run. You say you were doing wheelies? Did the exhaust get clogged with something? If you have air fuel and spark and compression, check exhaust flow. I know, it's rare, but it happens.

 

[r_chez_08]

it must have something to do with timing. because it acts like it has an advanced flywheel key.... i dont understand how it suddenly choked out and died then wouldnt restart. it was running great.

Sheared key?
If it doesn't start on test fuel, and has spark and compression it is probably a timing issue.

 

[Keit1212]

cereal box? At napa you can buy Gasket material for like 9 bucks. I can make tons of gaskets with it. There made for gas/oil/coolant and such. not like a cereal box

 

[r_chez_08]

Lets be honest, gasket material is pretty much card!

 

[Bluethunder3320]

yesterday i realized the gas we put in was "premium". so i drained all the gas and put regular in. it showed signs of starting but never got it to start.

today i went over again. same thing, but now it woudnt even pop. there was a little smoke coming out the exhaust. the plug was drenched because of the flooding from priming it 100x... cleaned it off. then it showed a little sign of running. then i drained more gas to get the regular gas into the bowl.

then it ALMOST started.... it would run for a split second then die. and only weakly. it was teasing. now it wont even pop.

i dont think a jet is blocked because it should run for longer off a shot of gas


he might just go for a predator now. if i cant figure it out

 

[OzFab]

Ok, so, it's getting plenty of fuel; have you double checked spark? If there's a bad connection on a kill switch it would cause your problem &, TBH, it sounds electrical...

 

[B.M.800]

Check the coil. My honda had some of the same symptoms when the coil was dying...

 

[Bluethunder3320]

it has good spark when i ground it on the engine.

hmm... maybe i should check coil gap

 

[slideways]

I had one just like this. It was on my "uncle in law's kids kart". I put the greyhound on for them and they used it for awhile and then started having issues with it just plain not running one day. Suspecting bad gas i tried the usually carb rebuild and fuel swap and got nowhere. One time it would start up and run on a stand for awhile and then wouldn't restart. Next time it just wouldn't start at all. But they had the warranty and i had already tried one of my good carbs on it and it ran ok that way. So i put all the crappiest clone stuff i had on it and told him to return it. That was after i put a brand new one on out of my pocket he never paid me for.

Moral of the story is i got screwed but i think there was a fuel flow problem somewhere in the little fuel valve/filter deal attached to the carb you simply cant fix no matter what. Either that or the fitting in the tank had a casting problem.

 

[Badot]

Is the low oil sensor disconnected? That might have gone bad, if it's still hooked up. If it's disconnected, make sure the wire's not hitting the block.

 

[Blazkowiez]

If you know fuel is reaching the engine then I wouldn't spend much time on it. Consider what your time is worth vs the worth of this engine. I will make these points for you.

- Check the carb make sure the emulsion tube is clean and the main jet isn't clogged, check full flow on the shut-off valve and that the bowl is clean.

- Chinese powerpacks suck on these engines, the few times we've had engines that didn't run on these it typically ended up being this problem. When you get the new pack (15 used from a local shop if they are fair) make sure you gap it properly against the flywheel. Obviously if you are checking this by this point you've already checked the spark plug and made sure it was firing.

- If it were a sheered flywheel key it would be backfiring when trying to start. I haven't seen one sheer on a clone yet.

Do you have a good local source for parts like power packs? Or is your only source now a new predator?