Draining old power steering fluid?

[Iceni John]

Are there any tricks to draining the power steering and hydraulic fan motor fluid?   They're both supplied by the hydraulic pump, in my bus a Webster K-series, with one pair of hoses for the steering box and the other pair for the fan motor and fluid cooler.   I've drained out about 4 gallons so far, but I suspect there's still lots more left to drain.   I jacked the front axle up so I could turn the front wheels lock to lock, but that only resulted in a dribble more fluid coming out the reservoir's drain.

I need to drain out as much as possible because the old fluid is almost black and has probably never been changed for a long time.   I have a new hydraulic fan motor to replace the old one that was leaking internally, but I don't want to keep using the old fluid in it if it's contaminated.

Would it be a dumb idea to blow a few PSI of air through the return lines, or could that bugger up the steering box or pump?

Thanks, John     

[luvrbus]

John, I use Lubegard in pressure cans from O'Reilly's since I don't have the machine 2 cans will do it @ 13 bucks a can

[Iceni John]

That's an ATF protectant that may be useful later, but for now I just want to get as much of the old fluid out so it doesn't contaminate the new fluid any more than necessary.   Unfortunately there's no drain valve on the PS return line  -  I've ordered two Fumoto valves for the PS reservoir and the hydraulic fluid cooler, but maybe I should also put another one on the return line at the steering box itself?

Everything I'm doing now is to solve my overheating problem, but I also want to make it easier in the future to do routine maintenance such as changing fluids.   I've got a new radiator core and a new fan and fan motor, changed both thermostats and the fan's temperature switch, installed three new temperature gauges in the engine room, checked the water pump, and replaced coolant hoses and new hose clamps.   I'll also install a Derale 65k BTU transmission fluid cooler to reduce the heatload into the coolant.   It's not cheap to do all this, but neither is a new engine.

Thanks, John     

[Scott & Heather]

John I wonder if cliff was suggesting that the lubeguard pressurized cans would help push the old fluid out?


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[Beesme]

I really like the series 50 idea . I was under he imession that it was not possible or attainable... What exact motor and tranny do I look for or out of what bus ? Thanx so much for the info !!!!!!

[Iceni John]

John I wonder if cliff was suggesting that the lubeguard pressurized cans would help push the old fluid out?


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Aha, I get it now!   So he and I were thinking along the same lines, just that he knew of a good product to use instead of me blowing air through the hoses like some redneck hick would do.   I'll certainly use the Lubegard if it will do the job easier and better than my way.

Always learning!

Thanks, John