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690E Low hyd flow & pressure

Alberta Cowman

Well-Known Member
Joined
Nov 3, 2015
Messages
48
Location
Alberta
Hi guys. I've been following for a few years but here's my first post.

I've got a 690E and it has low flow and pressure on all circuits. I can only get about 3700 psi and the cycle time is at least double normal. It will only somewhat move in HD mode. It had the pump rebuilt about 2 years and 400 hrs ago. This problem showed up while it was shut down for lunch. Worked good in the morning then hardly move itself around after. I've checked a few things and am running out of ideas.
- Changed the pilot circuit filter and found nothing in it when I cut it open.
- Adjusted the pilot circuit shutoff valve as it was out of adjustment.
-Checked the pilot circuit pressure.
-I checked the system controller and had to increase the high idle speed. There is some slop in the throttle linkage. This helped somewhat.
- Tried increasing the main system relief valve.
- Checked the load sense pressure differential.
- The suction line to the main pump was changed when the pump was.
- The tank is staying pressurized.

In the service manual it says to check the Load sense relief valve but I can't find a procedure for it.

I picked up a new set of fuel filters and the main return filter in the hyd tank and will put them in the morning.

Any ideas? Thanks.
 
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