Coleman UTV 400, a few issues

[gregj]

New UTV owner, but not new to motorcycles, worked as Suzuki mechanic in H/S and college, as well as raced a lot of amature MX.  So I am not uncomfortable around engines.  That said, wife decided to get me a UTV for Xmas, and the local Tractor Supply had one that fit the bill, so we took it home.  We only have 10 acres, so I intend to use it putting around the place,  etc.  Been running premium with some Sea Foam in the gas.  Only have 4 hours on it, but so far there are 3 things that are driving me nuts:  1) vibration when taking off, almost feels like loose motor mounts.  I suspect this might be the CVT,  maybe belt break in, and may be just the way they are.?  2) stalls when stopping.  So far it seems to do it mostly when it has not been run for a few min, or after a long stretch down the driveway and stopping quickly.  I put a new stock plug in it, that seemed to help.  I have a couple of Irridium plugs on the way.  3) Tailgate rattle.  I hate noises and rattles.  And as rough as it is when it takes off, it really rattles the tail gate or box.  I have tried to isolate any and all components, but so far have not been 100% successful in identifying it.     TIA

[Manfred]

I bought one last april. You will have go over every nut, bolt,  etc to make sure they are tight. grease all available fittings. Also front and rear diffs were low on fluid. Make sure you follow breakin period.  might be missing rubber bumpers for box. mine runs great, haven't had any issues other than that noise on initial takeoff. I have 70 miles on it. it does run better with time, make sure you use 91 octane in it.

[Swede InTexas]

Had mine 25 hrs, piston rings broke caused engine failure, in shop waiting for new engine.  Still under one year warranty!

When failure started I found fouled spark plugs, very dirty looking, then changed to new plugs, but failure soon followed.