aefron88

Gear oil on what? Front or rear axle? Which model?

Thanks for the picture writeup! I haven't had that issue yet with my UT400, fingers crossed, but I'm glad someone posted detailed instructions and pictures if I need to do it eventually.

I believe it's just a standard H6 bulb so any H6 replacement should be compatable. There are tons of LED options available.

New, There is no way to adjust the fuel/air mixture manually. The ECU adjusts automatically based on the O2 sensor in the exhaust just like a modern car. I can't see a pic of your plug, care to upload one? If you have excessive carbon build up it may be too low a heat range, or you may have something else going on. What model plug did you uave installed?

That means the tank is empty. First make sure there's fuel in the tank. Next lift up the seat and check the wire connector going to the fuel tank on the passengers side. Make sure its not loose.

what size engine? got a picture of what you're talkng about? it should be a lip type flange seal that seals the shaft from oil leakage

I haven't seen any factory fit type covers, but you can probably measure and find a universal. I don't have a 550 to measure but something like this would probably work

The blower on that heater and a reasonably sized light bar should be fine. With the Chinese noname light bars the wattages get large quickly. The stock halogen headlights on these UTV's I believe are only 35 watts, so I think like a 40-80 watt light bar would be plenty.

I've never seen a spec published anywhere, maybe someone will chime in. I doubt theres enough overhead to run an electric heater that puts out enough to be worthwhile. My experience with these types of things is there might be 10-15 extra amps of overhead MAX at idle, quite possibly less. A 100 watt light bar will eat half of that. A 100 watt electric heater would eat the other half and isn't going to heat the cab. If you feel like experimenting you could keep adding load until the battery voltage is <14V at idle, that will give a good idea of the max limit. Dont forget to turn on the factory lights (35W ea), brake lights (10W ea), turn signals (10W ea), etc as all that has signifigant draw.

Hey Greg, I'll be interested to hear what the actual root cause of the failure is. My assumption was weak splines + torque. It could be the splines are not proper spec metal or not heat treated properly. I've seen a couple posts of the exact same failure now. Based on the sizing I wouldnt expect any issues as these things don't make that much horsepower. Either way good luck, and keep us posted.

Welcome. If you have any questions there's plenty of info in the coleman and hisun forums (it's a rebranded hisun, but most of the 400 posts are in the coleman section) there's a couple posts in each about things to help quiet these machines down. People have had good luck with adding various sound deadening materials under the front/sides of the seat and under the bed. I would love to see a post about the heater setup with some installed pics. I've seen them listed but you're the first person I've heard of actually installing one on a 400.

Looks like you've been busy. Glad you got it all running right!

No one sells a tune that I'm aware of. With HUD ECU hacker you can adjust the fuel map and a few other limits. You would basically need to play with it and adjust. Factory fuel map is set to meet emissions, prevent damage to the engine, and make it operate smoothly. If the engine is in good shape you can likely get away with a little more fuel and a little more spark advance without any issues, but it's not a big displacement motor and there's no way to adjust the valve lift or timing so you're not likely to get more than a couple HP max, just not worth the effort without making other modifications.

Have you adjusted the spring preload to max for starters? Keep in mind the coilovers are not the only reason for the weight limit; vehicle weight balance, frame strength, and max tire load are also limiting factors for the max safe load. I'm not aware of any upgraded coilovers available, but I'm sure you could find something and make it fit if you wanted. It's just a function of spring weight and length between the mounting points.

You didn't answer my other question, are you hearing the fuel pump come on for 5 seconds or so when you turn the key to "on" before starting? And you do have fuel in the tank correct? I'm also assuming with the key on you aren't getting any "P" codes on the display. If all that is good I would go after the spark plug next, then valve lash (if it hasn't been checked recently), and then the injector

So what exactly happened between Nov 24h (when it was running, correct?) And today. Have you used it at all? Did it give you any issues? So just to confirm you have 12.8V still at the battery, it cranks over, but doesn't start? You have fuel in the tank? When you turn the key to "on" but don't crank it do you hear the fuel pump hum for 5 seconds and then stop?

The rear is always locked on these by design. There's no way to change that unfortunately. The wire you are seeing is probably the speed sensor.

You get something like this to mount the light bar to the round tube. You can mount the switch anywhere you can get wires behind. The spot you mention is the ugly for where the ignition used to be on the older 400s. Should be doable. You will need to run wires from the battery under the seat, underneath the body up to the dash and up to the light bar. A pack of zip ties will be needed to attach the wires so they don't just flop around and chaft on stuff or catch on things. Order a kit with the wiring harness and we will be happy to help you get it all set up. I know it looks daunting but it's a lot easier than you think and most people are more than capable of completing the project with a little guidance. The best way to learn this stuff is by doing it! You've got this!

No worries, not sure on the hole location. Got a picture? It's very possible a low oil situation can toast the wet clutch quickly, as can a wrong type of oil situation. The manuals for these things have a mixed messaging on what viscosity and type of oil, but it should be MA2 rated due to the wet clutch just like any wet clutch vehicle. Modern conventional automotive oils have viscosity modifiers which can cause the clutch to slip and once it starts it goes downhill quickly. Being an automatic (CVT) it can be harder to noice a slipping wet clutch unlike on a motorcycle. Sounds like you've got a big project ahead. Post lots of pics and what you find/do as it can always be helpful for the next guy.

Glad you got it apart. You can do a rough test by just making sure it's open between the two pins at room temp and closed at higher temp (which would turn the fan on) more than likely it has failed if the fan is running well. The fuse box is under the seat on all 400s. The 550s/750s etc it's under the hood. The Hisun produced how to videos mostly cover the 550 and 250 models, and there are a few changes.

They use the same EFI system controlled by the Delphi MT05 ECU. Mechanically they are all similar, I would be surprised if your unit will not spit out error codes like the rest of them. Go ahead and give us more details of exactly whats happening and maybe we can point you in the right direction.

Yes

Yes sorry that's how you're supposed to check it. The point I was trying to make is people recommend you run the oil higher than the dipstick suggests. Checkout the documents on "Motorcycle Doctor" for more details. Not sure on the coolant drain as I haven't found a need to drain mine yet. I would steer clear of radiator drain plugs in general, as every time I've used one on a car it never seems to seal back up right. Personally I would just pull the lower hose. As far as the oil cooler, normally I wouldn't bother, but if the oil is all gunked up with friction material it's probably worth unhooking the hoses and blowing it back with low pressure compressed air. Another random thought, you might check the valve lash, especially on the exhaust as it may be sitting partway open, and the way the cylinder is tilted that valve stem seems to have oil puddled on it when sitting. I wonder of that might help leak oil into the cylinder? Its also entirely possible you have a stuck ring due to carbon, maybe a dry & wet compression test to see where you're at.

1. Yep they're known for this, the plow mentioned won't help with keeping the wet clutch plates alive. 2. I would check the compression and go from there. I haven't heard of a lot of ring failures. There are complete head assemblies as well as cylinders available for very reasonable prices. The recomendation is to go high on the oil. Motorcycle doctor sells an extended dipstick and tube for all models except the 400. The claim is that Hisun changed the dipstick shorter somewhere along the way and more oil helps prolong wet clutch life. 2.5. Every wet clutch motorcycle/atv/sxs I'm aware of shares engine and transmission oil. Make sure you use MA2 wet clutch oil. 3. Toe is the only adjustment unless you want to do the old shade tree method of bending parts to adjust caster and camber. I doubt most power sports shops have alignment tools anyway. 4. Not sure off the top of my head. There are user & service manuals available in the "downloads" section. The user manuals describe the clock adjustments. I think I covered most of your questions.

Just digging around on the machine since I haven't seen the sensor before I believe it is on the drivers side just above the coolant hose, on the rear of the radiator. It has a rubber cover zip tied over it. Hopefully your hands are smaller than mine 😂 it doesn't look all that fun to get to.