Engine turns over - won't start

[bbranden73]

I have confirmed I have spark, fuel and it appears to have compression, but will not start. It has backfired a couple of times in the past, but I am not sure why it will not start. Its a new GY6 engine that I purchased from you about a year an a half ago. It took me some time to install it and then have not ridden it much as I was completing the upgrade of the Dazon Buggy.
can you help me with this issue? I would like to get it running again. Thank you!

[PGH]

Start by checking your valve lash and thoroughly cleaning the carbuertor passages and jets.

[bbranden73]

so I cleaned the carburetor and the main valve and after reinstalling the carburetor I tried starting it again and it started to run for a few seconds and then stopped went back to doing what it did before. I cleaned it again and repeated the process with the same result. I thought it might be old gas so I removed all the gas and cleaned the carburetor again after adding new gas and got the same result. Any ideas? Is my carburetor bad?

[Frank]

Hi, make sure your vacuum lines are correct, only 1 goes to intake, on my gy6, had same problem when I bought mine. Previous owner had a t in line. One from top passenger side goes to intake. Bottom drivers side just hangs down. Hope helps. Frank

[bbranden73]

Thanks for the tip. I checked it and its all connected correctly. I still get the same issue. If I spray some starter fluid in the carburetor it will start for a min and quit. I am thinking my main carburetor jet is not working. I made sure the tiny holes were cleaned and still no luck. Any ideas?

[Frank]

On same note, make sure intake is not cracked, and hole is clear on intake for vacuum line. Proper gravity feed fuel filter, try starting with hand held over air inlet, filter off, maybe it will suck practical thru. Other than that, check valve adjustment. I replaced my carb., 20-40 bucks. You'll get it. Frank

[CheethaSpeed]

Air fuel mixture adjustment screw on the out/to engine side of the carb about center line on exit tinkering could help. There is probably a set number of turns for standard adjustment level, but idk exactly for gy6. Carbs can be tricky to clean and adjust if not familiar, so cheap a new one one eliminate any questions about it. If fuel is flowing to the carb at the closest line to the carb, you can eliminate problems pre carb fuel delivery. It was always some electrical part for me with my few gy6s. Good luck

[bbranden73]

thank you for the tips. It is now working. The main jet was severely clogged. I installed a new carb and its now running great!

My only issue now is how to get my brake pressure switch to work. I installed a new one and its either on or off with power the switch doesn't seem to be triggering with brake pressure. Any ideas?