Just replaced wheel motor and steering pump on SST 61-25CH SCAG Zero turn mower(estimate 10 years old as bought used 4 years ago). Now pump/ motor is some times slow to respond to steering control and seems to be air bound and/or not getting sufficient fliud flow. Have bled by unscrewing pump release, cycling control forward and backward 10 times,closing pump release and recycling control 10 more times. Any ideas or any other way to bleed the system? Thanks John
SCAG- Hydraulic Bleeding?
- Thread starter jelaff
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J_J
Super Star Member
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- Sep 6, 2003
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- JACKSONVILLE, FL
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- Power-Trac 1445, KUBOTA B-9200HST
John,
If you started the engine with a dry pump , you may be in trouble. It only takes a few seconds of no fluid at that rpm.
Put the machine up on jack stands, so the machine will not get away from you.
On some hydraulic pump systems, to bleed the system/pump, disconnect a plug wire, or something to make sure the engine does not start. Then open the bleed port, and some even provide a screw in fitting with a tube attached to catch the bleed fluid, and then use the starter to run the pump through several cycles to purge the air, when you see no more air coming out, you should be good to go with the pump section. I don't know if your system is an open loop, or closed loop system. You might be able to download the manual off the Internet. In some hydraulic systems, the pump draws the fluid from the tank, but with a closed system, the output is fed through the wheel motors, and back to the input. Any make up fluid is added to the system via the charge pump. The machine should be up on jack stands, when testing/purging the wheel motors. You should test the charge pressure and pump output pressure. That will tell you a whole lot.
lhfarm
Veteran Member
Did you get this fixed? Changing a repaired pump (blown seal, new bearing) and can't get the motor to work on that side. I think I have tried to bleed every fitting, but no luck.
Barry
RickB
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- Just a Scag
Go to Scag's website and download a manual for your machine. See if it gives a bleeding procedure. The manual for my Scag did.
lhfarm
Veteran Member
I have a Snapper and there is nothing in any of the manuals. They don't even tell you the capacity of the hydraulic system (basically they tell you to change the system filter, but never drain it). The pump blew a seal and wrecked a bearing or the other way around. In any case, the pump emptied the system for me.
Wish I had a SCAG.
Wish I had a SCAG.