Open center refers to the open central path of the control valve, when the valve is in neutral position. The hydraulic pump is a continuous flow type. ... Closed-center systems are always under pressure but oil does not flow until you activate a lever asking the system to perform.Sep 30, 2017
Another E hydraulic problem
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URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=183679
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Topic: Another E hydraulic problem
Posted By: Brian Jasper co. Ia
Subject: Another E hydraulic problem
Date Posted: 04 Oct 2021 at 7:12pm
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A while back I posted my hydraulic pump conversion on my E and it worked well to start with. As I picked, it got to where it wouldn’t pick up the header again and I noticed that the pump was extremely hot, hot enough to scald. I had a small automatic transmission cooler laying around and plumbed it it the return line. Didn’t seem like it helped at first, but after a couple hours of not lifting the header it started working again and the hydraulic lines were much cooler. Makes me think that there’s something in the main control valve that’s restricting pump flow and popping the relief valve. I’m wondering if the original pump that failed did so because the relief valve may have been stuck so the pump body broke. Any ideas? ------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
Replies:
Posted By: steve(ill)
Date Posted: 04 Oct 2021 at 8:24pm
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I dont know what valve you are using... MOST will have a pass thru port so the oil from the pump runs low pressure, THRU the valve and back to sump.. Just circulating... When you stroke the valve, you block the pass thru port and open a port to the cylinder to raise or lower..... SOME valves do not work that way... You could put a pressure gauge on the inlet to the valve ( from the pump) and check to see that you have a pass thru OPEN ..... The RELIEF should only work when you stroke the valve and send oil to the cylinder and it dead heads... or too much load. ------------- Like them all, but love the "B"s. |
Posted By: steve(ill)
Date Posted: 04 Oct 2021 at 8:39pm
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What is the difference between open and closed center hydraulics? ------------- Like them all, but love the "B"s. |
Posted By: DrAllis
Date Posted: 04 Oct 2021 at 9:31pm
| I don't remember how many hydraulic functions you have on an E, but one of the levers/linkages is STICKING, causing the hydraulic system to bypass. On a K or F it was usually reel raise when using the corn head. Maybe you are running full tilt in low gear and as a result the variable speed drive spool is sticking. Something is sticking "ON". |
Posted By: Brian Jasper co. Ia
Date Posted: 05 Oct 2021 at 3:01pm
------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
DrAllis wrote:Posted By: DrAllis
Date Posted: 05 Oct 2021 at 3:11pm
| It can't be the header lift sticking or the variable speed sticking because you would notice the header raising to the top and the variable speed increasing to the max all the time. Has to be the reel lift even if you're not using the grain head. |
Posted By: Brian Jasper co. Ia
Date Posted: 05 Oct 2021 at 4:17pm
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I’ll investigate that a little closer and report back. ------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
Posted By: steve(ill)
Date Posted: 05 Oct 2021 at 4:24pm
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Something is dead headed... Probably in the valve.. Either STUCK or by Design.. ------------- Like them all, but love the "B"s. |