2009 - Hisun 700 - Multiple Issues

[Joel Goldsney]

Wasn't sure exactly how to title this thread as I have a few issues with my newly acquired hisun UTV. Hopefully going to consolidate all the issues in one thread. 

I purchased from a guy who  had rebuilt the engine  replaced the fuel pump as well as re-done the front end. He had the unit running and driving when it quit and would not start. He got frustrated and decided no more projects and sold it to me.  Unit is in excellent condition physically.....hardly any scratches on the plastics. All in all its a good unit with the following issues/symptoms

1) Mis fire and stalling out when revved

Well as you can see by the title of the first issue I managed to get the unit running.  Seems that the battery was very weak. I charged the unit and it fired up fine.  The engine seems to stutter and misfire when revved and once the unit warms up it stalls out. I think it's a fuel issue as if I give it a shot of ether it starts back up.  

Additional Note: Revving engine in Neutral  seems to cause indication to flicker and occasionally the reverse light comes on  which seems to kick in the reverse rev limiter. Have also hade this happen when driving around. Reverse Light flickers and revs get cut. 

2) Fuel line configuration.

When he replaced the fuel pump he got creative with the tubing and removed the "small fuel tank" 

(See pictures)

Not sure  what the purpose of this tank is but would love some pictures of a stock set up so I can  put everything back together correct.

 

3) Issues engaging in gear

The unit seems to have issues going in to gear...I will move the shifter in place  but the gear won't engage and the lights don't indicate correct. It takes a few tries to engage and sometimes it grinds a bit 

4) Rack and pinion slipping

This problem is probably a simple replacement fix...when turning to the right with the vehicle not moving the steering just slipps and turns without turning the tire. I believe I just need to replace the rack and pinion but if there is something else please let me know.

Any insight or tips on resolving any of these issues would be much appreciated.

[Joel Goldsney]

Ok here is an update.

Issue 1 - Issue  is partly resolved....found a ground wire that wasn't connected gear selector lights no longer flicker and rev limiter isn't kicking in. Getting some backfiring when I let off the throttle abruptly bit but running much smoother 

Issue 2 - Still would like a picture of the fuel set up with the small tank....have been told it's a holding reservoir so the pump doesn't have to crank as much to prime. Have had a ATV tech recommend installing a check valve to prevent fuel from draining back in to the tank. 

Issue 3 is partly resolved as well have improved things a lot by adjusting the linkage (lock nuts had vibrated loose so it was incorrectly set). Still have some problems coming back in to neutral or getting low gear to engage. Need it bring shifter past neutral , almost in reverse and then back up to neutral.  Also have occasional problems getting low gear to engage ....shifter will go in place but gearing won't grab. I need to go to low , then to high and back to  low to get it to engage. 

Going to order the new rack and pinion later this week. It's drivable but you need to be aware that a quick evasive maneuver to the right may not work 

Not a bad looking unit for its age....

[Joel Goldsney]

Ok update to issue 2)

Massive thanks to Craig over at www.motorcycledoctor.com he was able to provide me with the  diagram below, now I just need to determine if it should be re-installed.

[Joel Goldsney]

Issue 4) Issue 4 seems to be resolved by tightening down the adjustment on the rack and pinion....there is a little slop in the steering now but no slipping.

[kenfain]

Great job! Doesn't sound like we could add anything. You got this. Good luck on this project.  It sounds like the linkage still needs a slight tweak. Thanks for the follow up,  and welcome to the forum! 

[Chuck_13]

That secondary fuel tank thing is kinda odd.I don't have much experience with sxs,spent ten years earlier in my life as a professional Honda mc tech,and I don't think Honda even at their wackiest would design something like that!Btw i have a 2010 Hisun 500 and it tarts fine.even without the extra tank.i would say if it works without leave it off-others with more time on these machine may disagree with me.Great looking ride!Really like the wheels you have.

[Joel Goldsney]

Thanks for the reply.....

I'm really tossed on the secondary fuel tank...I see a certain benefits but don't want to complicate things just because that's the way factory did it. 

 For some reason the machine l seems to occasionally get starved for fuel. Not sure if it's the current fuel configuration or not.   Having the gravity feed to the carb would ensure that fuel was there for quick starts and would provide a kind of surge tank if there were issues with the fuel pump consistently feeding.  

Current system has a T just before the carb that returns excess fuel to the gas tank.  This line always seems to have air bubbles in it. I'm wondering with the T being right near the carb if the fuel line to the carb is getting air locked some times.  ( I'm no mechanic  so there is a strong possibility that I don't know what I'm talking about) 😁

I have some fittings on order and may adjust the flow lines to a configuration similar to the Weller racing fuel set up for the Rhino 

https://www.wellerracing.com/Yamaha-Rhino-660-450-High-Volume-Fuel-Kit_p_8.html

Have read some good things about this set up...

Also may install a primer bulb on the feed to the pump to prime the pump before starting...

 

[Ben1098]

FUEL SYSTEM

Your unit is before FI and in-tank 40 PSI electric fuel pump.  The diaphragm fuel pump/pressure regulation mini tank set up has some issues.  The supplied diagram and routing is good.  The pressure required for the carb to accept fuel.....float valve is a nominal 3-4 PSI.  The height of the mini tank fuel level above the carb bowl fuel level only gives 1 to 1.5 PSI.  This is the pressure regulation of the set up.  PROBLEM...."vertical height" difference can be almost nothing when climbing up out of a steep sided creek bank or hill.....runs out of fuel when the demand is the highest.....the level in the mini tank is still the same, it is just the mini tank rotation downward....lower....as the UTV front rises.  I have moved the tank up higher.....less lean out popping but looks stupid mounted to the roll cage bar.

The Tee at the carb will let most of the fuel just return to the main tank....path of least resistance.  That has to go.  Now for the pump pressure over powering the carb's float valve....if you have a ring dent in the needle's rubber tip.....the mini tank clears that up.  Go back to the mini tank and see if you can live with the above mentioned flaw.

Check valve-----foot valve in a water well system-----I found that only one in tank pickup (gumdrop) will flow at the slight draw the fuel pump generates to crack open the check valve.  It also had a fine mesh screen to keep grass, weed seeds, etc. out of the fuel intake.

Alternate fix.......low pressure adjustable ELECTRIC FUEL PUMP from auto stores O'Reilly's.  Connect direct to carb hose barb.  With a remote switch, you can drain down carb before shut down AND then refill with "fresh gasoline" for easy starting.  Heat soak floods intake (expansion) and as an added bonus, the fuel looses it's POP.  used this trick on multiple golf carts that were hard to start.

 

SHIFT PROBLEM.  looking at the supplied image, notice the shift linkage adjustable rod....REMOVE one end coupling.  The lever bracket attached to the motor (actually the shift cam shaft) can now be pushed/pulled to find the shift point detents.  See if the dash gear selected LED matches when pushed into a gear.......checking the shift indicator switch.

NOTE:  the hard shift-grinding gears can happen if the carb idle speed is set TOO HIGH.....wet clutch is starting to engage.

You should have the gears at detent (possible bent shift forks if not)....NOW sync the shift lever to the detents...connect the rod back to bracket at motor.  ROD THE RIGHT LENGTH????  You found the adjustments (L and R threads and lock nuts)...find the correct length.  SHIFT LEVER moved between RNHL....ALL HIT CORRECTLY????  You can have one end but not the other

NOW for the BAD NEWS.....you will find out that you can get one end BUT not the other....ADJUST to the OTHER and the former now does NOT work..............................ANALYSIS  of what is WRONG......Shifter lever does NOT have enough travel to get BOTH ends to work.  SIMPLE FIX....The shift lever end is TOO SHORT....AND/OR....the motor shift bracket is TOO LONG.  Easy to fix......REMOVE the motor shift bracket.....there is a dog leg bend(offset) between the D hole and the ball end.  take the bracket and lay it down in bench with the "ball" up.  You need to save the dog leg offset SO go closer to the D hole (wider here about 25mm---1").  Take a center punch and mark (dot) close to the bend AND close to the D hole (but not too close for mounting screw and washer)...the punch marks are for the correct reassy of halves AFTER you cut the bracket IN HALF across the wide area.  1/8" to 3/16" with cutoff wheel is removed and then use a wire welder to make it WHOLE again----JUST SHORTER.  Bevel the edges, have punch marks on same side as it was before cutting, tack to have a FLAT bracket again, burn it in and trim excess.  With the shorter arm on the motor end, the same adjustable linkage rod travel will ROTATE the bracket/shift cam more.......READJUST the rod and should have enough rotation for both ends of gear selection.

[Sam5]

Great Infromation. Thanks .Can some confirm that , I am buying one title says Sunl - that the  2009 Sunl 700  was buit by Hisun and it is a 95% Yahama 2009 Rhino 700 clone. Friend is sells it to me  the issue is timing chain adjustor off for second time.  I see this adjustor / cam timing chain can be and issue. I see there is a manual chain adjustor one after market.  Any and all info on this issue thank you.  , he purchased a new on at Tractor supply. Thanks Sam

[jasonj]

I just purchased a 2021 Hisun Axis 700 from Lowes its got 200 miles on it now , Ive had a few issues ,its runs rough ,throughout the power band ,right from the store . Also rear brake sqeaks when reversing .It started cutting out a few weeks back i thought it was going to strand me but limped it home,replaced fuel and air filter and it runs again. I drove this morning and pulling in i noticed dummy overheating light was on .i shut it down and clincked ignition back on and No fan?? Im not electrically inclined and dont have a clue as to what to do?? any help would be appreciated. as im disabled i use a wheelchair now be cause of psoriatic arth. and its kinda hard to work on this thing. I kick myself for not spending the extra and getting a Honda but i waited * months for one to arrived and fianally got tired of waiting.I dont know if i screwed up ,im not really trusting this machine and being in Mohave Valley its 115 degrees every day.  Thanks again!

[kenfain]

You'll likely want to bypass the heat sensor, and make the fan run full time. I'm pretty sure there's a thread or two around here somewhere that'll walk you through the simple process. Maybe someone who understands this computer stuff can provide a link? 

[Grady]

Does anyone here have a wiring diagram? We have a 700 that’s experienced some wires bonding to one another from what looks to be some form of heat 😆, one man’s junk is another man’s treasure I guess