Evening all, I'm hoping someone can help me locate a problem I've got with the above. The tractor low hyd pressure alarm is going off; it sometimes will turn off when the engine is revved hard. Combined with that the pto is tuning when not engaged (it can be stopped by hand), and in top gear the tractor wont move off (its like the clutch is slipping). I assumed the main pump was worn so we changed that, but the same problems persist. Ive taken a reading off the spool valves ( im getting 2200psi at tick over, but no more even when revved) and the trailer brake which seems to be working fine. Any help or guidance would be appreciated. Thanks
ford 7810 low hydraulic power
- Thread starter Rugrat
- Start date
Once never replace a hyd pump without checking pressure and flow, the pto and dual power use l/p you have checked h/p not the same if you have fitted new pump which has a piggy back l/p on it so it should be ok as to check that one needs a special adapter so stick something on the pto like power harrow or baler and if it slips the chances are the pipe suppling the pto has come off or split, the h/p system uses just the main pump for lift arms but spools use that plus engine auxiliary pump mounted on rear left of engine.
Thanks for the replies.
Forblue; can I check if the pipe supplying the pto has come off/split? It does slip under load.
Newfarm; I assumed that by testing the trailer brake and getting up to1900 psi and it seeming to work fine would mean that it was unlikely to be that?? I will see if I have anything I can bypass the TBV and see.
Forblue; can I check if the pipe supplying the pto has come off/split? It does slip under load.
Newfarm; I assumed that by testing the trailer brake and getting up to1900 psi and it seeming to work fine would mean that it was unlikely to be that?? I will see if I have anything I can bypass the TBV and see.
livestock 1
Member
There’s a low pressure pump attached or piggy backed off the main pump by means of a small splined shaft (the pump in the back end) is that the one you replaced? Not the one on the side of the engine? Did you replace the whole lot?
Hi livestock1, the pump I fitted is the transmission mounted one
agrilineproducts.com
Hydraulic Pump suitable for Ford & Fordson - 83957379 E0NN600AC
Hydraulic Pump Gear Type (Transmission Mounted). Hydraulic Filter Required 50166, Dynamamatic version is part number 6050 Max Pressure 34 BarFlow Rate 37 LPM21 TeethClockwise Rotation
agrilineproducts.com
livestock 1
Member
Hi. It would come with the small low pressure pump attached?Hi livestock1, the pump I fitted is the transmission mounted one
Hydraulic Pump suitable for Ford & Fordson - 83957379 E0NN600AC
Hydraulic Pump Gear Type (Transmission Mounted). Hydraulic Filter Required 50166, Dynamamatic version is part number 6050 Max Pressure 34 BarFlow Rate 37 LPM21 TeethClockwise Rotation
The pto pipe can be checked to see if it has come out by removing round plate on left side of rear axle you can then put a hand in to feel pipe but to check it and or remove you will need to remove main pump again, it's held onto pto valve by an r-clip and has an o-ring never known one to come off, you may ne unlucky and have pto clutch pack worn along with dual power wear, the trailer brake uses h/p oil not l/p.
livestock 1
Member
The tractor shouldn’t slip if the dp is in low assuming it’s got dp
Does the pto work with the dp in low?
Does the pto work with the dp in low?
livestock 1
Member
Try and tap the priority valve under the seat. That has stuck in the past and given lower pressure to the spools. Pto and dp slipping is on low pressure side
D/P uses plates when in low resulting in slippage if worn or buckled, when in direct drive sealing rings worn will result in loss of pressure, priority valve gives priority to main lift not to spools it's the combining valve that allows rear engine mounted pump plus main hyd to combine producing high flow and max pressure to spools, if combining valve needs adjusting that is fairly easy to do but only to max of 2500 going higher will accelerate pump wear.
livestock 1
Member
I seem to remember loosing spool service and the valve under the seat being stuck. I thought that was the priority valve
Farmeraduk
Member
- Location
- Oxfordshire
Our pressure dropped, wouldn’t tip trailer etc. turned out brakes were coming apart causing all sorts of mayhem in the hydraulic system. Hope not!
Don't think anyone learns many, many years ago the first big county's duffered from brake plates breaking apart can't remember now if they were brass then carbon or visa versa, but both rear turret housing off diff out hyd pump off and everything washed out with TVO don't think gearbox was off but drain plug out to also wash out a major job, Fords never had a problem until the TSA carbon brakes which carries on today that shows up when changing rear filters.
You are not completely wrong the valve pack is called priority but there is no priority valve as such, it has three valves, unload, flow control and combining.
No where you have you gauge is correct if you have no pressure then 4/w/d would be in all time as well as d/p did you have this problem after fitting new pump, the l/p pump is driven by a small short splined shaft from main pump, when you got new pump it should have had this, so it might mean you taking out the pump again but i would also check h/p not at rear spools but direct from this pump.