Im totally new to tractors/hydraulics so please bear with my ignorance. I bought an old B7100, it ran fine for a while. Got hydraulic leak at block so decided to change some hoses, filter and fluid. Now the bucket barely lifts and wont tilt and leaks from left piston/ram. Also the rear scraper will lift but not tilt. Help please!
Hydraulics
- Thread starter BStevens
- Start date
85Hokie
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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
are you positive that everything is back exactly the way it was?
how long have you allowed it to run after the fluid change?
what filter you use?
and what fluid you use?
how long have you allowed it to run after the fluid change?
what filter you use?
and what fluid you use?
Russell King
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L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Since you changed hoses I would suggest you verify that you have the new ones connected properly and the same as the old hoses. Look at pictures if you took them beforehand
I used tractor hydraulic fluid, napa gold hydraulic filter, same as i took off.
There is always a chance imay have misplaced hoses. I Let it run a while and moved controls to work out air. I cracked a couple of the fittings on the pistons not functioning to check for vapor lock but fluid was present.
Question-hydraulic block has 2 lines, are they both pressure? Or is one a return. My tractor has a "riser" added on to the hydraulic fill with an inlet in addition to the fill cap, with a line coming from block.
Could the loader control have a bad valve effecting both the loader and scraper?
Welcome to OTT
Technically hyd system can have air in it but no vapor lock. Yes hyd valve could be faulty. I agree hose routing/connections should be checked.
TheOldHokie
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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
The line going to the "riser" should be coming from the loader valve not the outlet block so that in itself sounds wrong.
Check all three loader hoses to make sure they are properly routed:
- Pump pressure OUT from hydraulic block to pressure in (P port) on loader valve
- Pump pressure OUT from loader valve (PB port) back to second port (pressure return) on hydraulic block
- Low pressure tank return from loader valve (T port) to the fitting on the transmission filler
Dan
Your current risk is in destroying your pump.
The B7100 hydraulic block used for things like a loader leaves the tractor's pressure relief valve out of the early part of the circuit.
The wsm instructions caution about ensuring a pressure relief valve is always in or before the loader valve.
A hose on the wrong place could be eliminating the loader pressure relief valve.
Hydraulics is not a lets try and see what happens opportunity.
Do your research following the advice given by Theoldhokie. Ask more questions if unsure.
Only once you are absolutely certain do you start the tractor.
Dave
The B7100 hydraulic block used for things like a loader leaves the tractor's pressure relief valve out of the early part of the circuit.
The wsm instructions caution about ensuring a pressure relief valve is always in or before the loader valve.
A hose on the wrong place could be eliminating the loader pressure relief valve.
Hydraulics is not a lets try and see what happens opportunity.
Do your research following the advice given by Theoldhokie. Ask more questions if unsure.
Only once you are absolutely certain do you start the tractor.
Dave
TheOldHokie
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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Yikes!!! I thought all of the tractors had a system relief in that outlet block. That is a very good design if you are in the replacement pump business. Just so happens I accidentally purchased a replacement pump for that tractor that I don't need and will sell very cheaply
Dan
I do have and study the owners manual and service manual, the problem is that nowhere can i find a clear hydraulics schematic for the two control valves. I replaced the hoses one at a time, thought i was ok. I'll keep asking with specifics, if you dont mind.
The tractor design really was only to have a system with the 3 pt hitch as the main hydraulic need and for that reason the relief valve is in the 3 pt control valve. The hydraulic block was more of an after thought in my opinion.Yikes!!! I thought all of the tractors had a system relief in that outlet block. That is a very good design if you are in the replacement pump business. Just so happens I accidentally purchased a replacement pump for that tractor that I don't need and will sell very cheaply
Dan
Dave
TheOldHokie
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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Specifics are good. Pictures are even better. What are the two control valves in question? Dave provided a very clear diagram of how an implement (loader) valve fits into the main lift circuit.
Apparrently your system worked fine until you serviced it so the operation of the valves themselves is not high or even on my list of suspects. More likely something about the service that was performed is causing your problem.
Dan
TheOldHokie
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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
The B7200 was the immediate follow on model and has the system relief in the block. Its hard for me to consider a standard equipment factory installed outlet block an afterthought. Rather simply too much expectation and trust placed in end user knowledge and understanding. That was recognized and corrected with the follow on model.
Dan
If you will answer a question and check for certain marks I can be more specific in helping you.
Clean off the top of the loader valve body and then look for letters protruding from the casting. Specifically, look for P or IN, T or OUT.
How many hoses connect to the loader valve body. & and your valve will have a power beyond feature, 6 and it has been plumbed following old practices where the Out or Tank port of the valve was used as a power beyond port feeding the 3 pt hitch through the hydraulic block.
Today's valve are limited to 450 psi on the tank port so it is not wise to use it to feed other stuff as the pressure can rise to 2,000 + psi.
Dave
Clean off the top of the loader valve body and then look for letters protruding from the casting. Specifically, look for P or IN, T or OUT.
How many hoses connect to the loader valve body. & and your valve will have a power beyond feature, 6 and it has been plumbed following old practices where the Out or Tank port of the valve was used as a power beyond port feeding the 3 pt hitch through the hydraulic block.
Today's valve are limited to 450 psi on the tank port so it is not wise to use it to feed other stuff as the pressure can rise to 2,000 + psi.
Dave
If you have what you are calling a riser on your fill cap then you should have a total of 7 hoses on your loader valve. Your loader valve should have a pressure , tank and power beyond port. The hose to the riser should go to the tank port.