B21 HST Problem?

[TexasB21]

I have a B21 that I purchased new in 2006. It has 250 hours on it and I ran it low on hyd fluid due to hose leak on job. Went to load it on trailer and it would not move. Put in 1.5 gal of fluid and barley got it on. Replaced both filters,fluid and inspected screen. It now does work in Low but not like new, Mid it squeals on take off and in Hi it really squeals and trys to move. The trans filter I removed would not drain. Cut it open and it was full of fluid and the element was black. At the time I was using the backhoe and might of had the selector in the 3 point position. Also the manual says that the system holds 7.26 gallons of fluid but mine only took 6 gallons and it is very high on the dip stick even after running it. I have the hydraulic hose for the backhoe connected back to the return line and lever in the 3 point position. Ordered the WSM. I'm going to remove and inspect the HST filter tomorrow. Also the fluid I drained was cola colored and glittery. Thanks for any input and I hope I did not ruin my rig.

 

[North Idaho Wolfman]

Might need the clutch adjusted too.
If the clutch is slipping it will make it seem like HST is having issues.

 

[TexasB21]

Might need the clutch adjusted too.
If the clutch is slipping it will make it seem like HST is having issues.

Thanks for the info. Never thought about clutch adjustment. Cant wait to get my manual.

 

[TexasB21]

Update. I replaced the trans filter and adjusted the clutch as per the owners manual with no big improvement. Cut open the filter and all was clean and now the fluid is at the proper level. On a flat surface in Low it moves fwd and rev fine but struggles and whines when driving back on to my concrete slab. Come on WSM.

 

[North Idaho Wolfman]

Is it in 4wd?

 

[TexasB21]

Is it in 4wd?

No it is in 2wd and the problem is the same in 4wd. And thank you for your assistance. Also the tractor rolls real easy in neutral.

 

[North Idaho Wolfman]

Do you have PTO powered implements?
If you do some thing like a tiller or a mower works great.
If the clutch is the problem then there will be a noticeable change in both the tractor speed and performance and the implements performance.

 

[TexasB21]

Do you have PTO powered implements?
If you do some thing like a tiller or a mower works great.
If the clutch is the problem then there will be a noticeable change in both the tractor speed and performance and the implements performance.

No PTO implements. The guy at the dealer showed me the HST troubleshooting flow chart from the WSM and after filter replacement I believe it was to check some relief valves. Looked at Illustrated parts book online and saw 4 P R valves on the HST unit. Thanks once again.

 

[TexasB21]

Also Wolman, I put the rear up on jack stands and in HI @2200 rpm's jammed on the brakes and the engine bogged down with no slipping so I believe the clutch is doing it's job.

 

[TexasB21]

Received my Service manual and the flow chart says to do a (Check and High PSI relief valve) check. Very simple check if you have the Hydraulic Test Gauge kit. My question is can I just go get a metric fitting, some adapters, hoses and gauges and make my own or by a kit for my tractor. The service manual is very vague.

 

[North Idaho Wolfman]

For a standard hydraulic pressure test, yea make you own hydraulic test setup, but if you getting into the HST there is liable to be very specific adapters needed to attach to the ports and be able to read the pressures.

 

[TexasB21]

Thanks once again Wolfman. Went to the dealer and talked to the service rep and I am now waiting on a call after he talks to the lead tech on the floor about the fitting that screws into the Neutral relief valves that take a 27mm socket to remove on top of the HST unit to perform the check.

 

[Shadow]

Was the flakes kind of gold colored? If so, that's the valve plates that have been scored and ended up in the oil. If that's the case, more than likely going to need a HST

 

[TexasB21]

Was the flakes kind of gold colored? If so, that's the valve plates that have been scored and ended up in the oil. If that's the case, more than likely going to need a HST

Yes the flakes / glitter was gold.

 

[North Idaho Wolfman]

Well sadly test or not sounds like you have your answer.
Now rebuild or used is the next step.

 

[TexasB21]

Just looked at the parts list and found the Valve Plates that shadow mentioned. If it comes to replacing the HST I might just inspect everything and replace the plates.

 

[TexasB21]

Was the flakes kind of gold colored? If so, that's the valve plates that have been scored and ended up in the oil. If that's the case, more than likely going to need a HST

The service manual says to" inspect the valve plates for wear and scratches, run finger across. If scratches are felt replace." No thickness parameters given.

 

[Shadow]

If you cancatch them with your fingernail, you need to replace them. I would say as much flakes as you found, you'll be replacing them and the pistons at the very least.

 

[TexasB21]

Shadow I was just saying what the manual says for inspection criteria. My rig is still together doing the troubleshooting.

 

[TexasB21]

Stopped by the dealer and talked to a tech who said I can get a fitting and hoses and gauges to do the check. Went to the hydraulic place and found out the threads on the relief valves are British 1/2-14. They made me a 0-5000 PSI test line for $56.00. Get home do the test according to the manual and the highest psi I reached was @ 50. So I'm with Wolfman about the special fitting they use to check this. If there is no special fitting and the test I did was correct the next step the manual says is to inspect the Charge Pressure Relief Valve.