Joe Breaux

STAY AWAY FROM ANYTHING FROM MASSIMO ..trust me on this , or you will regret it

well, after a dozen phone calls and emails to customer service at Massimo Motor Sports, someone finally called me back.. First he claims he never go my emails and messages , then said well its out of warranty, even tho its been overheating since the day I bought it new at Tractor Supply, and Tractor supply and Massimo have record of it, I was just out of luck.. They wont even give advice.. Great company eh? When I pressed him about all the 500 and 750 MSU s overheating, he admitted the Hisun motors are junk and they stopped using them 2 years ago.. his phone call was recorded ... So any of you with MSU 500 or 750s, be aware Massimo could care less how much they break down, THEY GOT YOUR MONEY.. so its now going to repair shop for its 5th time in just 300 miles on it

I took it to the local Massimo authorized shop, he kept it 3 days . Said it was just air lock.. brought it home, first 2 hours or so was fine.. then light came on and radiator was ice cold again.. This thing only has less than 400 miles on it . it runs perfectly otherwise... I guess it must be the gasket allowing gas into cooling system, but it shows no evidence of leak in the exhaust or oil.. it must be a very tiny leak. I will bring it back to him tomorrow .. I found out, Hes the only one in the area that will work on them... I wish I had bought the Honda instead. We have 4 Honda machines. thousands of miles on them, never any issues on any of them..

well so far no joy on overheating.. got water circulating at idle for an hour and a half .. radiator warm, no hot light.. run it down the trail half throttle, 10-15 minutes , HOT LIGHT ON... radiator cold again.. someone please tell me what the hell is going on... no water in oil, no misfire on start, no white smoke at start or running down the road.. driving me nutz

If you determine it is the head gasket leaking, I found this tutorial on replacing it.. seems fairly simple ..https://www.vectorutv.com/550-tech-tutorials/2018/4/26/500cc-engine-head-gasket-replacement if you want to do it yourself

sorry to hear that. ...Is water circulating? Any misfire or white smoke on start up? That's a dead giveaway, air bubbles in radiator while idling ? / check oil for signs of water dilution

I bought mine new in 2017.. it has always run perfectly.. It goes thru anything in 4 WD Lock... You are right the T-Stat is on the bottom of engine .. a real pita to get at .. Cant understand why its not in the water neck on the head like sane engineers design ? Thanks for the info.. I ll run it on the trails next weekend.. I hope its cured..

thanks a lot .. I will do that after T-Stat is done.. how does air enter a closed system, I wonder .. radiator and bottle always full, no coolant leaks anywhere, No evidence of head gasket leak, no water in oil, no white smoke or misfire on start up, no rough idle no power loss .. The machine runs perfectly all the time.. just no water circulating. This is the first issue its had in 3 years

found no air in system.. water is not circulating.. will remove thermostat today.

Massimo Tech finally called me back just now .. There IS a Thermostat. underneath the engine..... I asked about air pocket being the cause , they advised to jack up machine in front , remove caps on Radiator and recovery bottle and run it . watch for burping . I ll try that first ..

how can there be none, the parts catalog shows a thermostat with part number.....just no location .. I have tried calling Massimo but they never call me back

Got a 2017 Massimo MSU500 UTV with thermostat malfunction.. hot light comes on in 4-5 minutes but radiator is ice cold... where exactly is it? The hose neck on the head has nothing in it. I was told it was down by oil drain plug.. only thing I see is water pump.. Is in inside pump housing? Cant find any exploded diagrams that show it.. how to I remove it? any help would be appreciated