Engine Surge / Stall on John Deere EZTrak z445


Old 08-24-11, 12:16 PM
Thread Starter
Join Date: Aug 2011
Location: USA
Posts: 2
Received 0 Votes on 0 Posts
Engine Surge / Stall on John Deere EZTrak z445

Hello and thanks in advance to anyone who can help me.

We purchased a new John Deere EZTrak Z445 zero-turn mower in 2009...it has the 25hp Kawasaki V-Twin engine. I performed the yearly maintenance with the kit from the Deere store earlier this year (oil, filters, plugs); it has just over 60 hours on it now.

A couple weeks ago, I noticed the mower throttle surging up and down during operation, but it stopped after a few moments. I was almost finished with the yard, and I didn't think too much about it. The next week when I mowed, it started surging again and then the engine began bogging down in heavier grass...this is odd because NOTHING bogs this mower down. Right after that, the engine died. I let it cool for a moment and started it back up. For a few minutes it ran okay then it started dying on me again. Each time I would have to choke it to re-start it. When I would engage the blades it would go dead...I kept re-starting and finally it started going dead even before I would engage the blades. I put the mower up and finished the yard with our old Cub Cadet.

The next day I pulled the gas tank off and drained it (there were a couple small chunks of trash/debris in the tank). I pulled out the gas filter and blew it out (there was a small chunk of trash in it). I checked the spark plugs and they were very black...I cleaned them up, checked the gap and put them back in. I checked the oil and it was perfect. I checked the air filter and it was clean and properly seated on the carb.

I took it out and ran it hard for 10 - 15 minutes. It ran great, and I put it back in the garage, thinking problem solved. I got it out this weekend and had the same issues. Sometimes I restart it and it runs fine for 15 minutes or so and the same things start happening. Other times, I have to let it cool for a few minutes or it will just die over and over.

Any ideas? Again, I appreciate any ideas anyone has.
Sponsored Links
Old 08-24-11, 08:20 PM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 17,250
Received 22 Votes on 19 Posts
Try loosening the gas cap when it starts surging and see if it gets better. It may be developing a vacuum in the tank because of a clogged gas cap vent. Otherwise I would say water and/or trash is in the carburetor.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Ask a Question
Question Title: