Some of you may remember my Post about my B2601 breaking in half!

ruger1980

Active member

Equipment
L4310 w/La682, L225
Oct 25, 2020
331
120
43
CNY
You have described my problem exactly!
When the pressure is two great the valve pops and my pedal goes soft. In my case though the valve is doing this prematurely.
Is the problem both forward and reverse? As I asked before is the PTO engaged or disengaged when this occurs? If you lift the travel pedal and lightly apply again does travel come back?
 
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ACDII

Well-known member

Equipment
B2410, L352 Loader, Woods BH70-X backhoe
Oct 21, 2021
660
407
63
Illinois
Follow the troubleshooting in the manual.

1653259258155.png


1653259292086.png




I dug up the manual and looked at the diagram. I see where the HST gets its oil from now. Makes more sense what the poster above indicated RE the PTO and charge pressure.

1653259911065.png


14 is the power steering pump, which pressure not used by power steering is directed at the PTO clutch and then through the filter, and into the HST. I would assume you already replaced the filter. If power steering is OK and PTO engages all the time, but still have loss of power, I still suspect the PRV is the cause. There could also be a restriction between the filter and HST.
 
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Egressman

Member

Equipment
B2601
Sep 7, 2016
140
7
18
Richmond, IN, United States
Is the problem both forward and reverse? As I asked before is the PTO engaged or disengaged when this occurs? If you lift the travel pedal and lightly apply again does travel come back?
PTO seems to rob some power

Tractor can not overcome the brakes in either direction.

I removed both relief valves, nothing remarkable about them!

Why one is $250 and other is $140, no noticeable difference. Spring is the only thing that could be different. I can mic them and lay side by side to compare? I’m not sure if there’s any benefit to be gained from that but I will probably do that tomorrow.

I tried adjusting in both directions, got worse when I loosened or released spring tension and increased its length!

seemed to be a slight bit better when I tightened the tension and shortened it.

My observation was, make it longer to push it in deeper, if you tighten it, it becomes shorter and I believe it would allow fluid to bypass sooner.

The spring that is behind it is a very weak spring that pushes it in the hole.

When theplug is removed, the spring just pushes the plug out. I just touched my megnent to it and the valve main body came out. Less then 2 ounces of fluid came out of each hole.

Tractor has power with very little rpm, above idle it drops out. If power drops out the pedal is free, only mechanical tension on it.

It feels like it dropped out of gear when it happens, the tractor just lunges and starts to slow unless I’m on a hill and then it rolls free fwd or backwards.
it feels like something breaks every time.

But it doesn’t! All I do is release the pedal and drop the rpm and it kicks back in! I also come to a full stop so nothing in the drive train is damaged, it is not a “Shift on the fly” tractor lol

Steering has gotten worse over the last couple of days.

3pt still unaffected

Bucket power is good, just very slow because rpm is low and it can be jerky at times.

I might need a big white board to lay it all out!
Follow the troubleshooting in the manual.

View attachment 80538

View attachment 80539



I dug up the manual and looked at the diagram. I see where the HST gets its oil from now. Makes more sense what the poster above indicated RE the PTO and charge pressure.

View attachment 80541

14 is the power steering pump, which pressure not used by power steering is directed at the PTO clutch and then through the filter, and into the HST. I would assume you already replaced the filter. If power steering is OK and PTO engages all the time, but still have loss of power, I still suspect the PRV is the cause. There could also be a restriction between the filter and HST.
I own the manual, I have ran troubleshooting tables. Not seemed to resolve anything?

I only have a post hold driller and a bush hog that uses the PTO and also a landscape mower sorry. I have use the postal driller without any issues. I’m going to use it again tomorrow.

Today I used a ripper to lay UF wire, it was slow but it got it done.

And I think it’s worth saying that I really enjoyed the Miranda Lambert and Little Big Town concert I was out last night in Indianapolis.

Everyone has to appreciate some Miranda Lambert.
 

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ACDII

Well-known member

Equipment
B2410, L352 Loader, Woods BH70-X backhoe
Oct 21, 2021
660
407
63
Illinois
If power steering is failing, I think you solved your problem. The pump is bad. According to the diagrams I posted above, power steering is supplied by an engine driven pump that is inline with the power beyond pump that drives the FEL and 3PH. The power steering pump also supplies pressure for the HST to function.

Since the power steering is before the HST, check pressure going to the steering unit first, if good pressure, then it could very well be the steering gear causing it.

I didn't catch that the power steering isn't working, I thought it was, sorry to mislead.
 
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ruger1980

Active member

Equipment
L4310 w/La682, L225
Oct 25, 2020
331
120
43
CNY
PTO seems to rob some power
This seems to point to an issue with the steering/PTO/charge pump circuit

Tractor can not overcome the brakes in either direction.
I would think the travel function should be able to drive through the brakes in low range but not High range

I removed both relief valves, nothing remarkable about them!

Why one is $250 and other is $140, no noticeable difference. Spring is the only thing that could be different. I can mic them and lay side by side to compare? I’m not sure if there’s any benefit to be gained from that but I will probably do that tomorrow.

I tried adjusting in both directions, got worse when I loosened or released spring tension and increased its length!
By loosening the adjustment and spring tension you are decreasing the high pressure relief setting and by tightening you are increasing the setting.

seemed to be a slight bit better when I tightened the tension and shortened it.

My observation was, make it longer to push it in deeper, if you tighten it, it becomes shorter and I believe it would allow fluid to bypass sooner.
The relief valve serves 2 functions one is charge check and the second is high pressure relief. The high pressure relief operation works by acting on the stem inside the spring loaded cartridge. That cartridge actually can move inside the bore and is held in place by the weaker spring. This in effect is the charge check valve,

The spring that is behind it is a very weak spring that pushes it in the hole.
As above this holds the cartridge in place to provide the charge check function.

When theplug is removed, the spring just pushes the plug out. I just touched my megnent to it and the valve main body came out. Less then 2 ounces of fluid came out of each hole.
Normal

Tractor has power with very little rpm, above idle it drops out. If power drops out the pedal is free, only mechanical tension on it.
This again points to an issue with the steering/PTO/charge pump circuit

It feels like it dropped out of gear when it happens, the tractor just lunges and starts to slow unless I’m on a hill and then it rolls free fwd or backwards.
it feels like something breaks every time.
Another sign of steering/PTO/charge pump circuit issues

But it doesn’t! All I do is release the pedal and drop the rpm and it kicks back in! I also come to a full stop so nothing in the drive train is damaged, it is not a “Shift on the fly” tractor lol

Steering has gotten worse over the last couple of days.
Another sign of steering/PTO/charge pump circuit issues

3pt still unaffected

Bucket power is good, just very slow because rpm is low and it can be jerky at times.
Both of the 2 above items use a separate section of the hyd pump so only related on the inlet side.

I might need a big white board to lay it all out!

I own the manual, I have ran troubleshooting tables. Not seemed to resolve anything?

I only have a post hold driller and a bush hog that uses the PTO and also a landscape mower sorry. I have use the postal driller without any issues. I’m going to use it again tomorrow.

Today I used a ripper to lay UF wire, it was slow but it got it done.

And I think it’s worth saying that I really enjoyed the Miranda Lambert and Little Big Town concert I was out last night in Indianapolis.

Everyone has to appreciate some Miranda Lambert.
Please see comments above.
I still see a common theme in the charge pump circuit. You may either have insufficient flow to the charge circuit or internal leakage. Either way you still need gauges in the forward and reverse test ports to diagnose the problem