2555 throttle response

[Jabonee]

Got a question for you out there for those who have a 2555 tractor. I noticed on the one I have seems to be a bit sluggish on the throttle response. Told this was the nature of the beast since it is flyby-wire. Anyone out there notice this?:confused3:

 

[Uncle Hulka]

Noticed the same thing on mine. I assume it's directly related to Tier IV emissions, as well as being throttle-by-wire. A dealer apprised me of this behavior early on. I haven't found it to be an issue.

One behavior I didn't expect, was that when I have engaged the rear PTO, it is not possible to exceed the pto-rated engine rpm, regardless of throttle position. And I'm not talking about implements that require high horsepower either. It does this even with my 3-pt leaf blower!

 

[Jabonee]

Noticed the same thing on mine.

Thanks for the confirmation.Is your tractor HST? If so is the engine real sluggish and weak in high range?:confused3:

 

[akax50]

Thanks for the confirmation.Is your tractor HST? If so is the engine real sluggish and weak in high range?:confused3:

Hey Jabonee, I have the 2555 hst and I have never noticed any sluggishness with throttle or high gear. We traded a very new John Deere for our Mahindra and the JD had both of those problems. Found out that part of the problem with the JD was a throttle postion sensor that was replaced just before we traded it.

 

[Uncle Hulka]

Don't know if this is normal, but I just discovered that even without the PTO engaged, I am unable to get the engine RPMs above 2,400 (pto speed). Yesterday I mounted a 3-point hydraulic reservoir/pump (30 gal if memory serves) to power my FEL-mount Erskine snow blower. I believe this requires about 45-50 hp. I did a test run and at first (with cold hydro oil), I couldn't get engine rpm above 1,800. WTF?! This was the first time the engine had been put under any real load. I let it run awhile. With the oil good and warm, I could now reach about 2,150-2,200 rpm. I know the pto on a 3555 HST is rated at 42.5 hp, but shouldn't I be able to reach at rated pto speed with the blower doing nothing but, well, blowing?

 

[Jabonee]

Hey Jabonee, I have the 2555 hst and I have never noticed any sluggishness with throttle or high gear. We traded a very new John Deere for our Mahindra and the JD had both of those problems. Found out that part of the problem with the JD was a throttle postion sensor that was replaced just before we traded it.

AKAX50 Is you tractor equipped with"Load Sense"? I notice on the tractor I have here if the load sense is not on the tractor won't get out of its own way in high range.:confused3:

 

[Jabonee]

I'm wondering if the PTO has a load sense like the HST tractors do. Only delivers RPM when Load is applyed. Does seem strange you could not reach 2,400.:confused3:

 

[Uncle Hulka]

I do have a push-button switch identified as "LOAD SENSING", but I didn't turn it on. I had forgotten all about that little bugger. Hmmnnnnnn......I wonder if that could be part of the problem.

I won't be able to test until the weekend, but I'll report my findings here asap.

Can anyone here explain, in real-world terminology, what exactly "Load Sensing" is and how it would limit my engine speed when it's not engaged?

 

[oldpilgrim]

I'm wondering if the load sensing thing is like the smaller lawmmowers that used to have a spring on the carb that would speed up the engine if the engine sensed a load. Some people called it a governor. There was a paddle that used the flywheel generated wind and would move and pull on the spring.


It didn't control max rpms, as in a limiter like most governors do, but gave you more power when you started to get bogged down.

 

[Uncle Hulka]

I'm just hoping I'm making the rated 42.5 hp at the pto. This was one of the main reasons for buying this tractor in the first place. Realistically, I won't know for sure until the first snow storm. And no matter how impatient I am to know the answer, I am NOT going to be the one responsible for wishing the first snowfall of the season into existence!:snowflake:

 

[Nortac]

I'd like to hear more about the RPM, I am purchasing a 2565 Shuttle Cab, non HST...I'd hate to have issues out the door. I borrowed a new JD tractor and it had issues with RPM and not interested in starting that over.

 

[akax50]

Jabonee, our 2555 does have "load sense", but we never used it. I have noticed that during the summer operating in high range to move the tractor around generates a tremendous amount of heat in the HST system. 180+ degrees. No issues in the other ranges. Not sure if this is significant !

 

[Jabonee]

Can anyone here explain, in real-world terminology, what exactly "Load Sensing" is and how it would limit my engine speed when it's not engaged?

My Mahindra DSR explained "Load Sense" as keeping the engine RPM ahead of the drive load. Basically it destrokes the HST pump to maintain engine RPM's.

 

[Jabonee]

Jabonee, our 2555 does have "load sense", but we never used it. I have noticed that during the summer operating in high range to move the tractor around generates a tremendous amount of heat in the HST system. 180+ degrees. No issues in the other ranges. Not sure if this is significant !

180 degrees is about right for summertime. Remember rule of thumb for hyd temp is 100 degrees above ambient temp.:thumbsup:

 

[akax50]

180 degrees is about right for summertime. Remember rule of thumb for hyd temp is 100 degrees above ambient temp.:thumbsup:

Yea, my point was not that it was running too hot, just way hotter in high range than in the other ranges. I assume that the difference is pressure related. Again, not sure of significance to your issues?

 

[Uncle Hulka]

My Mahindra DSR explained "Load Sense" as keeping the engine RPM ahead of the drive load. Basically it destrokes the HST pump to maintain engine RPM's.

I appreciate you replying. Do you or your DSR knoe if load sense has any impact on PTO load (or vice versa)?

 

[Jabonee]

I appreciate you replying. Do you or your DSR knoe if load sense has any impact on PTO load (or vice versa)?

No mention of load sensing effecting the PTO. I'll ask next time I speak to him.:thumbsup:

 

[Uncle Hulka]

Much appreciated, Jabonee. If you have the time, could you explain what I'm experiencing please.

Regardless, thanks!

 

[DirtHauler]

When I bought my 2555 shuttle I noticed that there wasn't much throttle past a certain RPM point either with the hand control or foot pedal, so being the tinkerer that I am, I solved this (Mahindra and it's dealers won't like this!) by readjusting the brass cable stops at throttle control on the engine. I now have all kinds of RPMs even at the PTO.

 

[Jabonee]

Thought I'd reach out to you 2555 owners again on this thread. Iv'e this same tractor back now that the cold weather has set it. He's got the MIL light coming on. Of coarse its out when I get. I check the ECU codes and its pointing toward the EGR valve sooting up. Thats a indicator the engine is not being run hard enough. Anyway I noticed with this unit , a pawn cold start ,I cannot run the RPMs up that high.Now I'm not starting the engine and throwing the lever full bore. After a minute or 2 of warm up I advance the lever but just above low idle the engine begins to miss and spudder with little puffs of smoke. Anyone else notice this on there tractor?? Engine smothes out as the engine warms up. I'm wondering if my customer is impatient a running the tractor running rough causing the EGR to soot up quick. Any thoughts??:confused3: