Bleed air from CA hydraulics?
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Topic: Bleed air from CA hydraulics?
Posted By: JarrodACFan
Subject: Bleed air from CA hydraulics?
Date Posted: 16 Mar 2012 at 9:59pm
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Is it possible to bleed the air from the hydraulics of a CA other than just running the lift arms up and down? ------------- 1956 WD45 Narrow Front Factory Power Steering, 1953 WD Wide Front Allis Express in Muncie, IN |
Replies:
Posted By: Eldon (WA)
Date Posted: 16 Mar 2012 at 10:21pm
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Are you sure it is an air problem? If any water gets in the oil (possible bad boot on the gear shift??) it will cause the check balls to rust and stick in the pump....thus no pressure. Have to pull the pump, take apart (watch for flying balls and springs) apply air pressure to ports, clean and reassemble. ------------- ALLIS EXPRESS! This year: |
Posted By: David G.
Date Posted: 16 Mar 2012 at 11:11pm
I worked in a hydraulic shop for several years..... that's about the only way I know, best of all its free and no special tools needed. 
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Posted By: Gerald J.
Date Posted: 16 Mar 2012 at 11:31pm
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Bleeding is not generally needed for hydraulic power systems, only for low pressure hydraulic brakes. That's because at full pressure the air volume is very small, like 5% of an empty cylinder at 3000 psi (20 atmospheres) and that air is rapidly dissolved in the high pressure oil. So the next stroke its 1/20 that volume of air. It is possible to loosen a connection and bleed the air, but its messy and two or three strokes of the cylinder to full pressure is as effective. Gerald J. |
Posted By: JarrodACFan
Date Posted: 17 Mar 2012 at 6:59am
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I may have been wrong, it may not be air. When I raise the lift arms up, they are jerky. They brobably go up (the arms themselves) 1/2 inch, sotp, and then raise another 1/2 inch three times in a time frame of less than a second. (not sure on measurement or time) What do you guys think is wrong or is this normal? ------------- 1956 WD45 Narrow Front Factory Power Steering, 1953 WD Wide Front Allis Express in Muncie, IN |
Posted By: CTuckerNWIL
Date Posted: 17 Mar 2012 at 7:58am
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No weight on the arms would be my guess. Make the pump work by lifting something heavy. The cylinder packings may be dry also. If it sat for a time they can dry out or if they are too tight it will jerk like that without a load on it. Several cycles might lube things up and smooth it out.
------------- http://www.ae-ta.com" rel="nofollow - http://www.ae-ta.com Lena 1935 WC12xxx, Willie 1951 CA6xx Dad bought new, 1954WD45 PS, 1960 D17 NF |
Posted By: Eldon (WA)
Date Posted: 17 Mar 2012 at 10:21am
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Sounds like it may be starved for oil. If the oil level is fine, maybe an obstruction at the suction tube. ------------- ALLIS EXPRESS! This year: |
Posted By: JarrodACFan
Date Posted: 17 Mar 2012 at 11:20am
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Thanks, we are going to work on it today and I will see what we can do. ------------- 1956 WD45 Narrow Front Factory Power Steering, 1953 WD Wide Front Allis Express in Muncie, IN |