Power Issues With M126GX

[Craig3]

Hello all. I have been having a power loss problem with my tractor off and on for a couple of years. I have had multiple mechanics look at it (including the local Kubota dealer twice) with no luck. Here is a description of what has been happening:
2013 kubota M126gx. Tractor runs great under a decently heavy load (16ft discbine, 3rd to 4th gear in high range, anywhere from 60-90% engine load depending on terrain) for a period of time. It varies, but one example is that it ran well for about 20 minutes and then slowly lost power; engine load climbed to 100%, geared down and it dropped to 80% and then maybe one minute later, it climbed back to 100%, geared down and it dropped some, and rinse and repeat until I was only crawling at 1mph and just stopped. Let the tractor idle at 1000rpm for 5 minutes, and then I could cruise full speed again for maybe 2-3 minutes until the whole process repeated itself. And I can do this again and again and have the same results every time.

Fixes so far: all new fuel and air filters. All new fuel lines from tank to high pressure pump. Also deleted the dpf.

Any thoughts/ideas are much appreciated as I am at my wit's end with this thing!

 

[North Idaho Wolfman]

Needs to have a computer hooked up to it and read what's going on.
A dealer is about the only one that has that computer.
Could be a multitude of issues that could cause power issues like that.
If the computer was rewritten for the DPF delete, your issue could be there too.
Now I don't know about CA but in the US a Kubota dealer will not work on a tractor that's been deleted, so that could be an issue.

 

[Craig3]

Needs to have a computer hooked up to it and read what's going on.
A dealer is about the only one that has that computer.
Could be a multitude of issues that could cause power issues like that.
If the computer was rewritten for the DPF delete, your issue could be there too.
Now I don't know about CA but in the US a Kubota dealer will not work on a tractor that's been deleted, so that could be an issue.

Thanks for your reply. The issue was happening before the delete was done. The dealer worked on the tractor after the delete, but the problem is everything checks out on the computer when the tractor is at idle. And the dealer couldn't (or wouldn't) leave the computer hooked up while operating the tractor to see what happens when the tractor acts up under load.