Discussion:
Re: hydraulic fluid prime

the drain plug on our reach truck broke and all the hydraulic fluid spilled out. We fixed the tank and plug, refilled the tank, but now can't get the fluid to run through the system. Does anyone know if I need to prime the system, or how I can get the fluid to run through the sump and system again?
  • Posted 17 Sep 2019 09:09
  • By DTucker
  • joined 11 Jul'14 - 35 messages
  • California, United States
D. Tucker
Showing items 1 - 7 of 7 results.
LOL had me going for a sec there

glad you got it man
  • Posted 19 Sep 2019 06:45
  • By swoop223
  • joined 23 Mar'12 - 3,691 messages
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com
We found a small plug on the outside of the tanks aluminum cap housing, in between the body (you can see it through the vents that are covered with an expanded metal screen). Almost looks as if that's where you apply a fitting to pressurize the tank. We just stuck a hose in it and applied pressure. And kaboom, the tank exploded and we drenched ourselves in hydraulic fluid, no not really just kidding, it worked like a charm, it took about 30 seconds but it worked. Make sure you replace the plug before lowering the mast or retracting the forks, had to learn that the hard way.
Thanks Guys for all your help!!!!
  • Posted 19 Sep 2019 01:46
  • By DTucker
  • joined 11 Jul'14 - 35 messages
  • California, United States
D. Tucker
ok well after taking a look at the parts arrangement on the truck yeah i can see your problem. These trucks are built exactly like the CAT NR4000 series trucks, hyd tank mounted behind a cover on the RH side of the operator compartment and the hoses to the pump run down across and back up to the pump so yeah, it will gravity feed all the oil out.
You can try to pressurize the tank like brewski said but i don't think you have that kind of problem, because you obviously have oil at the pump.
I would check the M2 and M4 hyd valves on the hydraulic valve assy and make sure its getting a signal. M2 is for lift and M4 is auxillary.
  • Posted 18 Sep 2019 12:42
  • By swoop223
  • joined 23 Mar'12 - 3,691 messages
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com
Does your truck have a breather cap on the tank? If it does, take a air hose and a rage and pressurize the tank as best as you can and activate the pump, sometimes this additional pressure will allow the pump to prime.
  • Posted 18 Sep 2019 07:09
  • By BREWSKI
  • joined 10 Jan'12 - 1,699 messages
  • Nebraska, United States
BREWSKI
I was able to get to the suction line and started to remove it, but stopped because there was a lot of fluid coming out. I am afraid that if I remove the whole thing fluid will just keep gushing out and I dont want to have to use another bag of absorbent to clean up the mess. Should I try taking the output line off the manifold and run it?
  • Posted 18 Sep 2019 04:46
  • By DTucker
  • joined 11 Jul'14 - 35 messages
  • California, United States
D. Tucker
I am only able to access the output line down at the manifold under the floor plate (next to the dead man) in order to get to the output of the pump, I will need to remove the steer motor and/or lift the pump and motor. I am however able to get the output line at the manifold and crack that line but nothing happens, just some drips. I am unsure what the "suction" line is, I am assuming its the "feed line" (thats probably bad terminology but thats what I would call it). I can access it by moving the battery a bit, but this line connects directly to the bottom of the tank (which is full of fluid), its about a 1.5" hose, and I am afraid if I remove it from the pump all the oil will come out of the tank. I am also thinking this line should be full already because its below the tanks oil level.
Thanks Swoop, you are always a real help.
  • Posted 18 Sep 2019 04:02
  • By DTucker
  • joined 11 Jul'14 - 35 messages
  • California, United States
D. Tucker
You could try cracking the pressure line on the output side of the pump, that should let the fluid start flowing but this method is very messy.
One method i use is to take the suction line from the tank to the pump loose at the pump, get some hydraulic oil in a container, use a funnel and fill that line with oil. Then run the pump in brief bursts till it picks up the fluid and starts flowing.

Whats going on here is a hydraulic lock effect caused by the air in the line.
  • Posted 17 Sep 2019 22:25
  • By swoop223
  • joined 23 Mar'12 - 3,691 messages
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com

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