By Hi sun 500
hello everyone, i just joined this forum to try my luck, few days ago i bought an old (dont know exactly), 2011/14 hi sun 500cc ""carburated"", was not running at the time, but i fell was a good deal and decided it to bring it home to play with it, this is the issue, i bought and installed a new carb, and pump, i repositioned the battery location and upgraded to a "car batt", reconnected the fuel lines and started it, but it only runs with the choke ON, i checked the bowl, it does have fuel,but for some reason wont inject it to run, i came across a video that say that ""the body small tank had to be connected for the cart to run" (was deleted when bought), sure enough i got it to run sporadically , but the so called ""small body tank'' often runs out of fuel and wont refill itself , i had to couple times do it manually, so how does that small tank works ?..what does it do?..and why if bypass it , the cart wont start?....any help?..thanks so much!!!
Since I've seen some questions on this I took some pictures and will provide instructions on a valve adjustment for the UT400. This should be the same for the 550's and other various Coleman/Hisun single cylinder models with the cylinder slanted aft.
I have seen several people ask of it is really necessary, and read several reports of valves being out of adjustment from the factory. My valves were .004" intake, and .010" exhaust with about 5 hrs on the machine. I've seen different numbers thrown around for factory spec, but I decided to go with 0.005".
This is called valve lash. What is is is a gap between the rocker arm and the valve then the camshaft isnt opening the valve. Why does it matter? If it's too large the valve doesn't open all the way, if it's too small the valve dosent close. This can cause valve damage (overheating) as well as loss of engine power (burned fuel is going out exhaust rather than pushing the piston dow).
Tools required : 5MM Allen wrench, 10MM box wrench, needle nose pliers, flat feeler gauge set, rags
First you need to remove the fan cover on the passenger side. There is a cooling vent hose on the back side, remove the hose clamp and slide it off. From there there are 4x 10mm bolts holding the cover. The forward ones can be accessed from under the seat.
Next remove the spark plug from the drivers side. Carefully wiggle the spark plug wire off. Grip it as low as possible and give it a little twisting motion as you pull it off to help free it. Its a tight fit for a socket, but there is a sheet metal wrench in the toolkit that fits it. Unscrew the plug and set it aside. This allows you to spin the motor over freely with no compression to fight. When you reassemble this is a good opportunity to switch to an NGK iridium plug for better performance/less fouling DR8EIX)
Next you need to remove the intake and exhaust valve covers. The intake us the forward one. There are 3x 5MM Allen screws to remove. The Exhaust is the rear with 2x 5MM Allen bolts. Both covers have O-Rings instead of gaskets and are reusable. When you remove the rear be careful and use your rags as there will be oil that drips out.
Next up we need to spin the motor over to top dead center. Grab each rocker arm and give em a little wiggle up and down. Spin the engine over by grabbing the fan with your other hand. Spin the engine over until both rockers have some wiggle and are loose.
Once both rockers are loose slide the feeler gauge in like shown above. Try different feelers as needed to determine your starting spec. You should feel some drag but still be able to move the feeler without too much force.
If you need to adjust, use the 10MM wrench to slightly loosen the locknut, then with the correct feeler gauge in place, tighten the top square nut while wiggling the feeler in and out. Once you have it right you need to tighten the 10mm lock nut without moving the square head bolt. Once the lock nut is tight recheck the clearance.
That's it, button everything back up and make sure you have it all reassembled before running it again.
If you find this helpful give me a thumbs up or comment. If you have any questions or need more help let me know. If there's interest maybe I'll do some more of these
By Charles Hines
I have a 2022 Coleman 400 utv. I have added a heater with a 3 speed fan. I notice that while running with nothing on, the battery voltage gets to about 13,7 volts when funning at speed. If I turn on the lights, the voltage drops to about 12.3,if I turn on the heater fan with the lights on, the battery light will come on. I have replaced the battery with a higher capacity one and have replaced the regulator/rectifier, both have made no difference. I have measured the ac voltage at 22 vac at idle across all 3 phases, so the stator is charging. I have never had any issues with not starting or running poorly due to low voltage. Just wondering if there is anything I can do to increase the voltage from the regulator or is this just a underachieving system?
I have a 2012 Massimo MSU 500 that died. I found that it didn't have spark and the fuel pump wouldn't run. Checked all fuses and none were blown.
Went through and replaced the ignition coil, HT lead and spark plug. Still no spark.
Thought it could be the fuse/relay box because I didnt' know much about the machine at that point so I replaced it. No spark.
Then I replaced the ECM just because I was running out of ideas. No spark.
I removed the 9 pin connector and hardwired it making sure that they were no wires got swapped. Still no spark.
Then I replaced the wiring hardness. In doing so, I replaced the 9 pin connector with new ones. I made sure all wires were matched up between the engine harness side and the other harness assembly. Still no spark.
I have no other ideas what to do. My fuel pump doesn't kick on and I have no spark. I have 12V on the fuel pump, ignition coil and fuel injector, but no ground from the ECM control. I unplugged the fuel injector and waited for a diagnostic code but nothing ever came in. It makes me think that the ECM isn't powering up. I've checked for 12V on pins 18 (purple wire) and 15 (white and black wire). I also checked for ground on pin 2 (black wire). All are good.
I am out of options here and I have no idea what else it could be. I have all connections redone and are coated with dielectric grease. I've checked all easy things like fuses and making sure I have 12V in the right placed. I would appreciate any help.