Throittle Issue

Got2BTru · Jun 18, 2016

I have a Mahindra 2555 HST that I'm having a recurring issue with (been to the dealer now 3 times, though he claims he can't replicate the problem).

I'm out brush hogging on our 32 acres and after and hour or two if I have to stop to feed/water the dogs, replace a shear pin, etc. I lower the throttle to 800 or so RPM. When I get ready to get back to work, it won't go any higher than 1400 RPM (2400 needed for PTO Brush Hog speed).

Not sure if I can post a video or not, but I'll try..

Cramby · Jun 18, 2016

Have you checked your throttle linkage for slipping?

jmh1783 · Jun 18, 2016

That's pretty weird. I think these tractors have electronic throttles. I wonder if the computer thinks somethings wrong. Have you tried manually actuating the throttle on the side of the engine...to Cramby's point to make sure it isn't slipping. Also what happens if you let it sit at 1400 rpms for awhile, does it start to rise after awhile?

tkevan · Jun 18, 2016

http://www.tractorbynet.com/forums/mahindra-owning-operating/348870-2555-throttle-response-3.html

Got2BTru · Jun 18, 2016

tkevan said:
http://www.tractorbynet.com/forums/mahindra-owning-operating/348870-2555-throttle-response-3.html

TKEVAN,

I have checked this, thank you...it appears to be in the neutral position (I've NEVER moved it to be honest). What's interesting is as I read through that thread, I JUST had the exact other issue they referenced, the MIL check engine light error, which coded out to be a dirty EGR. My dealer told me the same thing, I need to run it at a higher RPM, I wasn't working it hard enough...

Cramby said:
Have you checked your throttle linkage for slipping?

CRAMBY,

I don't know how to check that personally, but I would *assume* the dealer did it any of the 3 times he had it in his shop?

jmh1783 said:
That's pretty weird. I think these tractors have electronic throttles. I wonder if the computer thinks somethings wrong. Have you tried manually actuating the throttle on the side of the engine...to Cramby's point to make sure it isn't slipping. Also what happens if you let it sit at 1400 rpms for awhile, does it start to rise after awhile?

JMH1783,

Yes, I can pull on the throttle cable manually and can increase the throttle speed.

If you notice from the video I took, the first 1/4 pull of the lever brings the tractor to 1400 RPM, but then simply nothing after that...it's ALWAYS happened after I've been running the tractor for a couple hours and stop/pause. If I let it cool down overnight it's fine the next time I go to use it.

Usmcsrt1 · Jun 19, 2016

I've had that issue with my 16' 2555hst after bush hogging for a while also. I just thought it was due to getting too hot so I would let it sit for a couple minutes and restart it and it would go all the way to pto speed. I've got approximately 42 hours now and it has happened 3-4x, but not as bad as your video shows. It would stop at around 2000 rpm or so.

jmh1783 · Jun 19, 2016

There's another thread here on an EGR problem with the 2555s. Not sure if this is the same problem or not. Keep us posted. The 2555 is on my short list.

Got2BTru · Jun 19, 2016

I did have an EGR issue, the dealer came out and cleaned it out. But this is unrelated to my throttle issue.

Worked for about 3 hours today...never let the throttle below PTO speed, even when I got out of the tractor a couple of times...I was fine all afternoon until I wrapped it up and tested....sure enough, when I dropped it below PTO speed, it would NOT go higher again.

I can't see how it's not something overheating...

dickfoster · Jun 20, 2016

Got2BTru said:
I did have an EGR issue, the dealer came out and cleaned it out. But this is unrelated to my throttle issue.

Worked for about 3 hours today...never let the throttle below PTO speed, even when I got out of the tractor a couple of times...I was fine all afternoon until I wrapped it up and tested....sure enough, when I dropped it below PTO speed, it would NOT go higher again.

I can't see how it's not something overheating...

Humm, beginning to wonder if it's not something related to the RPM sensor or the ECU heating up and weirding out. Of course it could just as easily be a related connection.