i dont know what to do...

[azndude3141]

im in a very bad situation. my minibike (cat 250x) has a bad engine. 3.5 hp briggs and stratton 2002 model. i brought it to the lawnmower shop at least 15 times and it still hasnt ran the way i wanted it to. every week. something goes wrong with the engine. and it pisses me off!!! it starts cold perfectly in 1 pull on choke, but the problem comes when the engine is already warmed up. i have to choke the engine whenever i want to start it even when its been ran for an hour and the engine dies every now and then when stopping and going up a slight hill. the only solution is to turn up the idle but by the time the idle is high enough, the clutch engages too early!!! :censure: it has a brand new air filter, new spark plug, clean carb, fresh gas, and fresh SAE-30 motor oil. im ready to buy a brand new honda gx 120!!!:shrug: or should i just go looking for an older 3.5 hp brigs and stratton engine? right now, my currnt problem is the kill switch doesnt work right. it only shuts off the engine when you press the button at an angle and it scares the sh*t out of me because spark fly out from the button. so what should i do, buy a brand new honda gx120, or an old used briggs and stratton 3.5 hp? i absolutly HATE these new picky carbs on the new engines. like mine...

 

[awkwardkitten]

It MIGHT possibly be a gas cap venting problem, or a tuning problem. Check the spark plug to see if it's running rich or lean.:shrug: I gave it my best shot, but what do I know?

 

[awkwardkitten]

o and with the kill switch, you might want to get a new kill switch. They are only a few bucks on OldMiniBikes, so if the one you have is malfunctioning, then you probably need a new one.
And if you do get a honda gx120, then you might as well upgrade to a 6.5 clone, they are on sale for cheap right now at harbor freight.

 

[azndude3141]

o and with the kill switch, you might want to get a new kill switch. They are only a few bucks on OldMiniBikes, so if the one you have is malfunctioning, then you probably need a new one.
And if you do get a honda gx120, then you might as well upgrade to a 6.5 clone, they are on sale for cheap right now at harbor freight.

i dont want the engine to be too big. i have a small frame and it can barely take a 5hp briggs. but seriously, i dont want a 6.5 hp...

 

[azndude3141]

o and with the kill switch, you might want to get a new kill switch. They are only a few bucks on OldMiniBikes, so if the one you have is malfunctioning, then you probably need a new one.
And if you do get a honda gx120, then you might as well upgrade to a 6.5 clone, they are on sale for cheap right now at harbor freight.

lol, and i like your signature. same here... :doah::hammer::shrug::crying:

 

[steven Durham]

Tuneing problem ?

im in a very bad situation. my minibike (cat 250x) has a bad engine. 3.5 hp briggs and stratton 2002 model. i brought it to the lawnmower shop at least 15 times and it still hasnt ran the way i wanted it to. every week. something goes wrong with the engine. and it pisses me off!!! it starts cold perfectly in 1 pull on choke, but the problem comes when the engine is already warmed up. i have to choke the engine whenever i want to start it even when its been ran for an hour and the engine dies every now and then when stopping and going up a slight hill. the only solution is to turn up the idle but by the time the idle is high enough, the clutch engages too early!!! :censure: it has a brand new air filter, new spark plug, clean carb, fresh gas, and fresh SAE-30 motor oil. im ready to buy a brand new honda gx 120!!!:shrug: or should i just go looking for an older 3.5 hp brigs and stratton engine? right now, my currnt problem is the kill switch doesnt work right. it only shuts off the engine when you press the button at an angle and it scares the sh*t out of me because spark fly out from the button. so what should i do, buy a brand new honda gx120, or an old used briggs and stratton 3.5 hp? i absolutly HATE these new picky carbs on the new engines. like mine...

Well if you have been to the lawn mower shop with the same problem that many times and it is still not right then I say look for another shop. I would look for another engine and a great one is the 5 HP Briggs with the bigger tank. Your carb shaft might be worn, out lots of things contribute to engine performance. The plug check is like an MRI for the engine, it's a way to see inside the engine from the outside. Best of luck and keep looking and learning that's the best route.
Steve

 

[125ccCrazy]

did you pull the carb apart and make sure all the passages are clean, the pick up tubes are clean and not plugged at the screens? what about a new diaphram and spring? clean any rust off the coil and flywheel then re-gap the coil?

 

[minibikedude]

I got a 3.5 Briggs with a bigger tank. I think its from the 90's, I had it running 2 years ago when I got it on a bike I bought, Drained out the fuel and oil. Had it sold on ebay once, and a deadbeat bidder didn't pay for it. Never relisted it. I would sell it to you if interested. I just do not use Briggs engines. I have it setting in my Kawasaki Coyote frame right now for a mock up engine, While I.m working on installing new jackshaft plates on it. It may need a new rubber gasket kit for carburetor from setting. but there cheap for these engine.

 

[125ccCrazy]

I got a 3.5 Briggs with a bigger tank. I think its from the 90's, I had it running 2 years ago when I got it on a bike I bought, Drained out the fuel and oil. Had it sold on ebay once, and a deadbeat bidder didn't pay for it. Never relisted it. I would sell it to you if interested. I just do not use Briggs engines. I have it setting in my Kawasaki Coyote frame right now for a mock up engine, While I.m working on installing new jackshaft plates on it. It may need a new rubber gasket kit for carburetor from setting. but there cheap for these engine.

Good looking engine Patrick, if azndude isn't interested what are you asking for it?...

 

[Yellowhand]

I'll bet the fuel pickup tube is partially clogged...

If you have to partially engage the choke to reduce the amount of incoming air to match the available amount of fuel coming through the tube, it's a sign that you don't have enough fuel passing through the $3 tube...

Each time this style of engine is allowed to sit unused with fuel in the tank, the very small fuel passage hole through the pickup tube begins to form a layer of varnish inside the tube, restricting the amount of fuel it will flow...

Left sitting long enough, the tube will close completely, and the engine will not start or run...

 

[azndude3141]

I got a 3.5 Briggs with a bigger tank. I think its from the 90's, I had it running 2 years ago when I got it on a bike I bought, Drained out the fuel and oil. Had it sold on ebay once, and a deadbeat bidder didn't pay for it. Never relisted it. I would sell it to you if interested. I just do not use Briggs engines. I have it setting in my Kawasaki Coyote frame right now for a mock up engine, While I.m working on installing new jackshaft plates on it. It may need a new rubber gasket kit for carburetor from setting. but there cheap for these engine.

i really dont want to have the trouble of haveing it shipped a long ways :doah:

 

[The Restore Kid]

Well if you have been to the lawn mower shop with the same problem that many times and it is still not right then I say look for another shop.

I'm gonna give a great big "I second the hell out of that one" :thumbsup:

They should have had it fixed right the first time, if not by time you came back a second time with an issue, he should figure out what your issue is...

Like mentioned before, gas cap, diaphragm, pickup tubes are all common problems..

Or, it might just be jetted too lean and is the preset jet carb so most likely needs a bigger jet.. Although sometimes you can run them a little loose and it will fix it, although they can fall out if they are loose.. :doah:

 

[azndude3141]

Well if you have been to the lawn mower shop with the same problem that many times and it is still not right then I say look for another shop. I would look for another engine and a great one is the 5 HP Briggs with the bigger tank. Your carb shaft might be worn, out lots of things contribute to engine performance. The plug check is like an MRI for the engine, it's a way to see inside the engine from the outside. Best of luck and keep looking and learning that's the best route.
Steve

my minibike wont fit a 5hp. lol and it will be wayy too lobsided. ill have to lengthen the pegs to fit my feet on