Challenger 750 - junk hisun motors!

[hisun junk]

I have a 2018 cub cadet challenger 750 with a broke chinese hisun motor and I know that I'm not alone! Almost all the places that were selling them in Colorado don't anymore due to the return for repairs on the clutches and broken timing chains! Don't have yours fixed because it will happen again! They just replace the broken parts with more junk chinese parts! I talked with a UTV mechanic that has replaced one person's clutch 4 times! I have people contacting cub cadet about these problems and also looking into complete motor replacement from hisun junk to a Japanese motor in which the chinese cloned their junk from.

[Joe Breaux]

you are preaching to the choir dude.. Hisun is as poor as it gets for quality. Massimo rep told me they stopped using HISUN and went to Linhai Motors because HISUN is pure junk ...I spent a lot of time and money keeping mine running.. I am told that a Yamaha Motor will interchange.. thats my next move 

[MitchSpence]

Let us know how the Yamaha transplant works. You may be onto something. 

[Joe Breaux]

I talked to an ATV / UTV engine rebuilding company rep.. He says the RHINO  engine will bolt right up to my Massimo.. Right now mine is running well, after a lot of work , money and some quality Yamaha parts . But when it goes down again, Its getting a YAMAHA transplant 

[hisun junk]

I'm in the process of getting the Yamaha motor which is the motor they cloned for the 750 in my challenger.

[hisun junk]

Joe,

Which ATV/UTV rebuild company did you talk with? Rhinos are getting hard to find. Which Yamaha motor are you looking at? The 660 is the one they used for cloning the 750 in my challenger.

Thanks,

Michael

[Joe Breaux]

Dont recall  the name of it.. I just Googled  UTV engine rebuilders ..Picked one,  I emailed the Owner.. he said he was 99% sure one of his YAMAHA  rebuilts would bolt up where my HISUN is now.. The Hisun is a Yamaha CLONE..  .. He also said it for any reason it did not, he would take it back.. He also had free shipping .. If mine fails again, I will likely go that route . Currently mine is still running 

[Jacob E freeman]

Well I have definitely got the same problem bought it brand new a 2018 cub cadet challenger 750 and have had it 2 years now haven’t been able to ride it more then a couple weeks at the time only 200 hours in and has a new timing chain tensioner all new clutches wet primary and secondary new belt new weights new spring new water pump new exhaust and it still over heats after 5 minutes of running 

[Joe Breaux]

you have air trapped in the head.  try bleeding out air at head and at waterpump  ....or .you have a bad head gasket .. Hisuns are not for riding, they are for working on 

[hisun junk]

I talked with the rep for the company that I purchased mine one 2018 and he went to the top dogs at cub and they said no warranty on the hisun junk and they quit carrying them. 
It will take a class action lawsuit in order to get cub to do anything!

They motor is a clone of the 700 Yamaha,  so I’m having one rebuilt and will post on the exchange when I get it to install. 

[Joe Breaux]

I know, Massimo said same thing..HISUN is junk, no warrenty, and they switched to Linhai motors  .. currently mine is running well but it has Rhino parts mixed in now... Let us know how the Yamaha swap goes.  Thats my plan when this HISUN croaks again 

[hisun junk]

Joe,

Motor is suppose to be done and shipped out in November. I’m going with after market clutches and will post when I start the exchange and post pictures as well. 
Michael

[Joe Breaux]

looking forward to seeing it 

[hisun junk]

I’ve done a lot of research on this swap and a good buddy of mine is an awesome ATV/UTV mechanic which gave me a lot of good info. hisun 750 (735cc) 38.22 HP Yamaha 700 (686cc) 50HP

That in its self is worth it!

[Joe Breaux]

When I was fighting with mine, I checked with a national UTV Engine builder.. He said 99% sure Yamaha Rhino engine  would bolt right up in mine.. he even said he would ship it free to me, refund it if not fit . just pay return freight ..

[flrtrader]

Why has this Topic been dropped?   I have a 2018 750 and would like more up to date information.

 

Thx

[Joe Breaux]

I know, I was waiting to hear if the swap went well.  I want to do mine too.  I wish everyone would come back and let us know what happens.. 

[hisun junk]

Well I finally got back to work on my junk hisun Challenger 750 UTV. I purchased what I thought and asked for a fuel injected 660 Yamaha motor out of a rhino or grizzly. The salvage place said they had one and would have it rebuilt for me. (the only way they sell their motors) The problem is hisun cloned the 660 Yamaha increased the bore & stroke to 102mm x 90mm from 100mm x 84mm. Identical motors, but the Yamaha was never fuel injected I found out when I went to install it. The place I purchased the motor said it was, I requested that it be a fuel injected motor and again the salesman had said it was. The 660 Yamaha was produced from '02-'08 but only with a carburetor. So no crank position sensor for fuel injection to work.   

So now I've tore apart the hisun junk motor and found that the cam/timing chain had come off the gears. It either stretched or the tensioner failed. The piston hit both exhaust valves and bent them. Dropped the head of at the machine shop yesterday for new valves and clean it up having them check the three intake valves plus all the spring pressures. The replacement vales and springs will be Yamaha as needed. The cam/timing and tensioner will be replaced with Yamaha parts as well. The piston and bore looks good with only two little nicks where valves hit.

The Motorcycle Doctor in Florida is a hisun junk dealer and has parts for sale on eBay or direct at 573-346-6867 or motorcycledoctor.com. I would suggest taking the time and use Yamaha parts when you can.

As you can see from pictures below the hisun has a different intake port compared to the Yamaha 660. That's what got me started into checking out the 660 motor not being fuel injected.

I get the head back in a 1.5 weeks, timing chain and tensioner is ordered, then I'll put it all back together and do another post.

Also if anyone needs a rebuilt Yamaha 660 for a rhino or grizzly '02-'08 let me know $2,750.00 shipping included.