Grasshopper model 729

66vette

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I just purchased a 2020 Grasshopper 729, having just sold my 2000 721. One noticeable difference other than more power and speed is the exhaust noise. On the 729 the exhaust sounds as if you are next to a wall and the exhaust is bouncing off it, that is when you are wide open throttle with the mower engaged and going about half speed. I find it somewhat annoying. My 721 had completely different exhaust noise, both had/have the 3 cylinder Kubota water cooled engine. One difference is the engine and muffler on the 721 was in an open area while the 729 the engine and muffler is in a full enclosure. What have others experienced. One other item, it seems the 729 uses more gas than the 721.
 

66vette

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I now see that the exhaust muffler glows bright red/orange inside the muffler. I don't believe this is normal, will call service department to repair.
 

66vette

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Service department found the problem. One of the coil packs was defective causing the engine to run on two cylinders instead of three. the unburned fuel from the deactivated cylinder was burning in the muffler. This Grasshopper was purchased new several months ago and now has 14 hours on it and has been running on only two cylinders the whole time.
 
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66vette

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The service shop is not concerned about the possibility of gasoline in the oil, gasoline washed away oil on piston/cylinder possibly scoring cylinder or burning out the muffler. I am concerned about those, what are your thoughts.
 

4getgto

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I'd be a little bit concerned. Did they tell you which cylinder wasn't firing.? Remember that as it could could come back to haunt you.
Hopefully not.?
 

gainestruk

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Be sure the work order says one cylinder wasn't firing on brand new unit, and keep that work order till warranty is over, one thing i would do is contact Kubota and tell them what happened and ask for an extended warranty on engine, they might not do it, but they might.
that way if engine problems show up at end of warranty both you and Kubota have a record of it.
My thought on it is it might have washed oil off cylinder causing scoring which will cause oil consumption, if it is still at Dealer ask the to bore scope the cylinder that was dead to see how it looks, other than oil consumption it could have damaged piston rings but that is less likley.
if it starts using oil take back to dealer and call Kubota.
 

66vette

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I was told they did contact Grasshopper and was told the Engine has a two year warranty and nothing further needed to be done. I did ask for the Grasshopper to be replaced or at least the Engine.
 

Hammermechanicman

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I would run a compression test on all cylinders and see if the non firing cylinder is different than the others.
 

66vette

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Got the Grasshopper back yesterday, in the process of mounting the enclosure and snow blower. Did send an email to Grasshopper technical department to advise them of the issues, still waiting for a reply.
 
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