GY6 150 boggs down at higher RPM

Posts: 19 · Newbie Joined: 02 Jun 2008 Posts: 19 Pictures: 0

Hello All. I am looking for some help with my buggy.
I have a gy6 buggy was running fine. Then all of the sudden to power seems to run fine at low rpm but once you hit the gas it seem to bog and has no power. I thought it was the carb so I replaced it with a new one. started right up but still did the exact same thing. Not sure what the porblem is I checked for fuel leeks and fuel filter all seems good.

Posts: 1869

1. Check for a vacuum leak between carburetor and engine

2. Check for electrical breakdown of the plug wire or bad spark plug

3. Adjust your valves

Posts: 1201

cptmiker check your intake for leaks sounds like the rubber has let loose around it, pulling air making it run lean on top end. more air then gas ,throws off the air fuel mixture ratio
pud

Posts: 19 · Newbie Joined: 02 Jun 2008 Posts: 19 Pictures: 0

Thanks for the info i will check the intake. on both sides of the carb. including the intake connection to the head. just to clarify. it runs fine at low RPM with i hit about 20% in starts to bog. I diraned the fuel tank replaced the fuel filter and the carb after the drian of the tank. I will also check the spark plug and wire to insure that there is no damage and that the plug looks good. I will let you know what i find. it was wierd when it happend it was going great and then all of the sudden instant bog at 20% throtle.

Posts: 19 · Newbie Joined: 02 Jun 2008 Posts: 19 Pictures: 0

I removed the intake manafold the rubber seal on the bottom looked a little flat but still over the edge of the seat. no crackes or holes. I reinstalled the manifold with a small amount of RTV blue gas safe sealent to insure a good seal just in case the O-Ring was leaking. the plug wire seems good no corashion or cracks plug looked ok might be running a little hot due to some white ash but in good shape cleaned and tested spak spark was bright. installed plug. reistalled everything else and started right up. same thaing. boged at about 20% throtle with load. when looking at the fule filter it looked like there was just a drip droping in from the takn side might be a poor fule filter and may be starving for fuel this was ok the last time i looked at it. picking a new one up will use one for a lawn more since a car ones filter is two thick and man for a fuel pump.

Posts: 93

Check your valve adjustment. Doesn't cost a thing. I just had this bite me in the butt. Mine started and ran fine just didn't have any power.

Posts: 19 · Newbie Joined: 02 Jun 2008 Posts: 19 Pictures: 0

anyone have a manual/proceduer as well as the specs.

Posts: 1869

GY6 service manual:

http://www.spiderboxperformance.com/yerf-dog-tech-center/yerf-dog-view_to pic.php?id=14

Posts: 1612

You could also be getting a weak spark from the coil wire.
Not a hot enough spark to ignite a ton of fuel.

Posts: 1869

Measuring the resistance of primary and secondary coils will tell you if there is short between coils. Cranking the engine, you can measure the input and output coil voltage.