Z122R stops running after about 1 hr

NormanB

Member
Joined
Jul 25, 2015
Threads
2
Messages
10
I bought this ZTR 10yrs ago (less than 400hrs) and it's run great until this spring. Recently it will run fine for about an hour at full throttle(~3,000rpm) then sputters and dies. If I let it sit overnight it will do the same thing the next day. If I run it at 2,600rpms it will run longer but still dies after about 1.5hrs. I can sometimes keep it running with the choke but it still wants to die after about 2hrs. If I disengage the blades when it begins to stutter it will often resume running normally without dying. I have replaced the fuel and air filters and checked the fuel line. And the last 2 wks it has started to smoke (blue) when I start it:eek: I change oil regularly.

Any ideas?
 

Auto Doc's

Lawn Addict
Top Poster Of Month
Joined
Sep 7, 2024
Threads
17
Messages
1,412
That has the signs of a failing ignition coil when hot. Just the same, a spark plug could also be breaking down and plugs are easy to replace.

When it acts up, use a spray bottle to shoot a stream of water on each exhaust pipe near the cylinder head. The water should burn off quickly if the cylinder is working, if the water does not burn off quickly, that would be the cylinder with an ignition spark plug or coil failing.

Use only a genuine Kawasaki branded coil (If it is the coil failing). Amazon coils are junk right out of the box in most cases. The same goes with spark plugs, get them from a local parts store and make sure the numbers match. Don't except the "it will fit" story when it comes to spark plugs. Spark plugs have different heat ranges that will affect the running performance.
 

NormanB

Member
Joined
Jul 25, 2015
Threads
2
Messages
10
Thanks for the info Doc. I forgot to mention that I just changed plugs. I never thought of the coils. I've had that problem on my tractor. I'll run the engine this evening when I get home and see if the problem is a coil. Thanks again.
 

DWSarow

Member
Joined
Sep 27, 2020
Threads
7
Messages
36
Did the coil change solve the problem?
 

NormanB

Member
Joined
Jul 25, 2015
Threads
2
Messages
10
My apologies for not responding sooner. My 99yo WWII veteran father passed away and it’s been a rough time around here. Unsolicited advice: put your affairs in order; your heirs will thank you. Anyway, I need a distraction now.

To address Doc’s suggestion, I mowed until it stopped and check the exhaust; both cylinders were working fine. The exhausts were steaming hot. I have recently changed plugs and both filters.

To recap, the symptoms are:
  • Stops running after about an hour. It just sputters a little and stops.
  • Sometimes I can keep it running with the choke, but I don’t like to do that.
  • Disengaging the deck when it starts sputtering sometimes keeps it running a few minutes but it
  • I can mow longer if I run at lower RPMs, 2600 tops.
  • Sometimes it puffs a little smoke when I first start it, blue smoke (yikes!).
  • Today it would only run about 20 minutes, and it ran rough. And I could not keep it running with the choke.
  • I have kept very good care of this machine. Changed oil, filters, and plugs per manual, blow it off after every use, and it stays inside every night. It has about 400hrs. Kawasaki FR651V.
 

Auto Doc's

Lawn Addict
Top Poster Of Month
Joined
Sep 7, 2024
Threads
17
Messages
1,412
My apologies for not responding sooner. My 99yo WWII veteran father passed away and it’s been a rough time around here. Unsolicited advice: put your affairs in order; your heirs will thank you. Anyway, I need a distraction now.

To address Doc’s suggestion, I mowed until it stopped and check the exhaust; both cylinders were working fine. The exhausts were steaming hot. I have recently changed plugs and both filters.

To recap, the symptoms are:
  • Stops running after about an hour. It just sputters a little and stops.
  • Sometimes I can keep it running with the choke, but I don’t like to do that.
  • Disengaging the deck when it starts sputtering sometimes keeps it running a few minutes but it
  • I can mow longer if I run at lower RPMs, 2600 tops.
  • Sometimes it puffs a little smoke when I first start it, blue smoke (yikes!).
  • Today it would only run about 20 minutes, and it ran rough. And I could not keep it running with the choke.
  • I have kept very good care of this machine. Changed oil, filters, and plugs per manual, blow it off after every use, and it stays inside every night. It has about 400hrs. Kawasaki FR651V.
Hi Norman B,

Sorry for your loss. I am a Veteran, and it is always difficult.

As for your mower problem, this is a classic sign of trash in the fuel tank getting sucked in until fuel is starved down. If you can run it with the choke for a little longer that is also a sign of fuel starvation.

Give use your product label information so we can better reference the design and parts layout.
 

NormanB

Member
Joined
Jul 25, 2015
Threads
2
Messages
10
Kawasaki FR651V
Kubota Z122R
 

Attachments

  • 20190530_065827.jpg
    20190530_065827.jpg
    1.6 MB · Views: 0
  • 20190530_065858.jpg
    20190530_065858.jpg
    1.3 MB · Views: 0
  • 20190530_065915.jpg
    20190530_065915.jpg
    1.8 MB · Views: 0
  • kubota1.jpg
    kubota1.jpg
    1.2 MB · Views: 0

Auto Doc's

Lawn Addict
Top Poster Of Month
Joined
Sep 7, 2024
Threads
17
Messages
1,412
Thanks NormanB,

That is the engine info, thanks for that, but Kubota does not build the engine.

What about the product label mounted on the mower chassis? That is what is needed to look up the design layout of the chassis and fuel supply system.
 
Top