Deere 310sj TMC - hydraulic rams not holding- leak down

[cbritt927]

Hey guys -
Deere 310SJ TC with approx 6k hours. Vin is 1T0310tjvao181944

All 3 rams are leaking down, even while running. Pretty quickly. Started happening at approx the same time. I can still dig but seems sluggish/slow and less powerful. Kind of dangerous with my guys down in the holes. Pump is still working is my point.

I just had one of the ram cylinders rebuilt, (it was leaking) and no help.

I do not believe it would be the valves that are strapped to the rams, because all 3 are leaking down. The main boom is the worst.

I am betting it's the bank under the seat. Have had external leaks there before.

Any advice where to start? Looking from the back, Looks like there are 2 valves with solenoids right were the big hoses come in. Perhaps I start there? New seals? Or new valves altogether. Don't want to take it to the stealership.

Please give me the bad news.

Thanks,
Clint.

 

[Dave Neubert]

check your pump pressure sounds like a bad main relief valve maybe seals are blown on it

 

[Diesel Dave]

I believe the solenoid valves on the control bank at the back of the machine (with the high pressure and return hoses running through it) are for the swing and extendahoe circuits.
With the b/ hoe functions enabled there is common high pressure oil and common return oil at each of the valve sections strapped to the 3 b/hoe cylinders.
I would start by checking the main boom valve section (strapped to the boom cylinder) for contamination since you described it as having the worst leak down of the 3.
Screen shot from the online parts below.

https://partscatalog.deere.com/jdrc/sidebyside/equipment/62503/referrer/navigation/pgId/676557174

.

 

[cbritt927]

Diesel Dave,
Yes, I see they are strapped to each ram on the hoe..... I guess I'm I wondering why all 3 of them have failed within a day or two of each other. It's interesting you used the word "contamination". A couple months ago the hydo-fill-cap somehow got blown off under the hood... A bit of dirt probably got in the tank. I can certainly pull apart that valve, but it just seems like the problem is upstream, meaning where those 3 valves receive their oil. I'm sure you are aware they are fed by the 2 main big hydo hoses that come from under the seat, that why it's confusing but I'm clearly no expert...

Thanks,
Clint