5020 throttle linkage adjustment

marcin · Dec 29, 2016

Did some more work on the 5020 over the past few days. I replaced the old leaking steering valve with a rebuilt one and rebuilt the throttle mechanism. I run into some problems with adjustment of the latter and was hoping I could get some help from the forum users.

I have not done any adjustments on the injection pump itself, as I am afraid to mess anything up. Otherwise, I have followed the instructions as written in the service manual. The problem I run into is that when I set the working range and fast idle speed to work correctly (i.e. within the correct positions on the hand throttle), I run out of space on the hand throttle to turn the tractor off (by cutting the gas). If I adjust the screws on the speed control rod to be able to cut the gas off completely, I cannot reach the correct working or fast speeds on the hand throttle. Is the problem with the injection pump adjustment or should I be working on the connection under the steering valve?

I am stuck and hope that someone who has dealt with this before could help me. Thank you.

Marcin

Tx Jim · Dec 29, 2016

My 1st thought is are you pulling out spring(key 6) loaded knob on the end of throttle handle to access stop &/or transport speed positions?

marcin · Dec 29, 2016

Tx Jim,

Yes, I rebuilt the entire mechanism and the pull out knob works correctly now. When I pull it out and turn the lever counter-clockwise I cannot slow the RPMs low enough to turn the tractor off (if the linkage on the rod next to injection pump is adjusted so that the RPMs are in the working range [800-2200] when the knob is in the "in position").

marcin · Jan 7, 2017

I have been waiting for some insight from users on this forum - I am a little disappointed about the lack of info thus far

I have tried working some on it this weekend and maybe I have some further clues. I noticed some play between parts #33 and #37 on rod #36. I took this apart and found that the hole for spring pin securing rod #36 to arm #37 was over-sized. I found a newer rod and re-installed - no more play. The problem is not solved or much better, however. I noticed that the issue is likely at the injection pump. The arm on the injection pump(connecting to rod #40) has to move a lot to get between low RPMs and shutting down - this is where I am losing a lot of my hand throttle movement. Is this normal? If not, how do I correct it? Please help:anyone:

beenthere · Jan 7, 2017

marcin
Don't be disappointed.. TBN members try to help whenever they can.. me thinks so far that your problem is "a problem"..
Hope with discussion continuing, that it will get solved.

Tx Jim · Jan 8, 2017

If speed control linkage has slack removed & one can't control speed to stopping engine then I'll guess inj pump linkage is worn. How many hours are on tractor speed-hour meter?

marcin · Jan 8, 2017

Impossible to tell, the tachometer and linkage were both broken when I bought the tractor. The engine was very worn out when it was rebuilt though. Pretty much everything else needed to be rebuilt also.

Yes, there is a lot of movement on the injection pump linkage between RPMs being below 600 and the tractor stopping, without the RPMs changing at all. It is pretty much as much movement in the injection linkage as is required to bring the engine throughout its entire working range. Can this be corrected without rebuilding the pump? I do not have 2K for a remanufactured one? thanks.

Tx Jim · Jan 9, 2017

Where do you live in Tx? I haven't had an inj pump rebuilt in several yrs. I would think one could get IP repaired for less than $2k. Last IP I had rebuilt was at Southwest Metro fuel in Richland hills,Tx a suburb of Ft Worth. (817) 589-1703 They were nice people to do business with.

marcin · Jan 9, 2017

Tx Jim,

Yes, you are right. I can get a remanned pump from Abilene Machine for less than 1K. I am going to get a new speed tube first to get rid of play to see what I get before jumping on the pump rebuild.

jenkinsph · Jan 10, 2017

marcin said:
Tx Jim,

Yes, you are right. I can get a remanned pump from Abilene Machine for less than 1K. I am going to get a new speed tube first to get rid of play to see what I get before jumping on the pump rebuild.

I have heard good things about Abilene Machine so far. My dealer and a large excavating contractor friend of mine have used them for quite some time.