JD 2550 pump question
- Thread starter MMagis
- Start date
Checked a few things over lunch:
Hi-Lo-no change on or off
PTO- no change on or off
FEL- no flow in neutral
The one thing I didn’t get to do was a flow test, I ran out of time.
We put a pressure gauge in one of the rear remotes again, the results may or may not mean anything concrete:
At idle the pressure was 0, as we increase the RPMs the pressure shot straight up to 2300 psi. Decreased RPMs and the pressure dropped back to nothing. This could be repeated over and over. There seems to be a knocking coming from the pump as the RPMs increase, but it’s tough to hear over the engine. But to be fair, I never listened for it before so I can’t say it wasn’t always there.
Hi-Lo-no change on or off
PTO- no change on or off
FEL- no flow in neutral
The one thing I didn’t get to do was a flow test, I ran out of time.
We put a pressure gauge in one of the rear remotes again, the results may or may not mean anything concrete:
At idle the pressure was 0, as we increase the RPMs the pressure shot straight up to 2300 psi. Decreased RPMs and the pressure dropped back to nothing. This could be repeated over and over. There seems to be a knocking coming from the pump as the RPMs increase, but it’s tough to hear over the engine. But to be fair, I never listened for it before so I can’t say it wasn’t always there.
Tx Jim
New Member
Get a laser thermometer and check for overly hot hyd components.
Tx Jim
New Member
steering valve,FEL valve,scv(rear remotes) if equipped with them
BAP
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Have you checked your hydraulic filter and made sure the intake screen is clean? Also, does the main hydraulic pump have the destroking kit on it? If it does make sure it isn't bleeding off the pressure. Check the coupler for the pump to make sure it isn't starting to strip out inside of it. It could also be the transmission pump going bad which feeds the main pump.
I apologize, I’ve not made it yet to check the temps. I hope to today.
I have changed the filter and cleaned the intake screen. Checked for a destroking kit, but it doesn’t have one (though it needs one).
According to the schematics in the tech manual, or at least my interpretation, the transmission pump shouldn’t affect the supply of fluid to the main pump. However, I question the accuracy of the schematics. There is more than one in the manual, and they don’t necessarily match each other.
The manual does have a step by step guide to troubleshoot hydraulic problems, and we’ve tried to follow it to a degree. But it would actually be cheaper to replace parts, starting with the pump, than to buy all the tools required to follow the guide.
I have changed the filter and cleaned the intake screen. Checked for a destroking kit, but it doesn’t have one (though it needs one).
According to the schematics in the tech manual, or at least my interpretation, the transmission pump shouldn’t affect the supply of fluid to the main pump. However, I question the accuracy of the schematics. There is more than one in the manual, and they don’t necessarily match each other.
The manual does have a step by step guide to troubleshoot hydraulic problems, and we’ve tried to follow it to a degree. But it would actually be cheaper to replace parts, starting with the pump, than to buy all the tools required to follow the guide.
I ran out at lunch to check temps. Let it idle for 5-10 minutes, then increased RPMs until it made it to full pressure. I worked the valves/steering for a few minutes and then checked temps. None really stood out as hotter than the others. Probably could have let it run for a bit longer, but everything basically stayed at the ambient temp after 15 mintues.
Tx Jim
New Member
Trans pump supplies oil to hyd pto,hyd hi-lo or reverser,brake valve,lube trans shafts """""AND supplies oil to frt hyd pump""""". Frt pump can pump supplied oil to hyd functions BUT can't SUCK oil
That makes sense. At this point I feel like I’m at a “chicken or egg” stage. The main pump only builds pressure at higher RPMs, and even that will quit after a while. I’m not sure how to determine if it’s the main pump not working correctly, or the transmission pump not supply enough fluid. I did determine that a rebuild for the main pump isn’t an option. The kit offered by Deere is just a seal kit, and a call to the local hydraulic shop revealed that they won’t even work on this type of pump.
I appreciate all the help.
I appreciate all the help.