RE;JD Seller origin of closed center hyd's.

JD Seller
This is what a US patent search revealed. I saw no mention of Mannheim,Germany although I suppose Mr. Van Gerpen Waterloo,Ia could have been a German.
Jim
https://www.google.com/patents/US2892311?dq=closed+center+hydraulic&hl=en&sa=X&ei=zzQGVJLoMYeQgwTwpIFo&ved=0CC0Q6AEwAg

Harlan Van Gerpen is or was as American as anyone I know. I met him once after he retired and the company I worked for helped connect him with an agricultural tire maker to help design a vehicle load simulator. He had worked on one that Deere used to put a load on tractors for testing. They called them puffers. Tractors that had the engines converted to compressors. The load could vary according to pressure pop off valves and which gear the transmission was in. They had to be ballasted quite heavily, and I think I saw 3 hooked in series to make enough resistance to test large tractors.
Harlan was a state senator in the 80's for several years.

I think it was successful farming was telling about Ford's select-o-speed trans. and said that the fellow that designed it went to work for Deere and developed the power shift.

That was Harold Brock.

TxJIm I don't know how you jump to where I said the closed center system was German designed.

I NEVER SAID THAT THE closed center system was a GERMAN design feature. I did SAY THAT the 20 series utility tractor was Mannheim influenced and leaned toward THEIR "new" design over the Dubuque engineer's design.

JD Corporate put out that they wanted a "new" utility tractor that did not have the 10 series problems. This was in 1962 or 63. Waterloo, Dubuque, and Mannheim ALL worked on design proposals for the "new" 20 series JD utility tractor. Some general requirements included a closed center hydraulic system. So all three design locations included that feature. Eventually Waterloo and Dubuque engineering was combined in Dubuque for the utility tractors.

The Dubuque tractor design proposal was slightly different than the Mannheim design proposal. They both had the closed center hydraulic system but they differed in PTO, driveline and chassis design. JD corporate chose the Mannheim design as the one they wanted to refine. So then both locations of engineers worked on the final tractor.

My friend always maintained that the Waterloo/Dubuque designed tractor was a simpler one. One of the differences he told me was the internal steel lines. The Mannheim designed tractor had them the Dubuque designed tractor had the external lines like the larger Waterloo row crop tractors.

You need to understand some internal JD cooperate politics too. The New generation Row crop tractors where such a hit that really gained JD market share. Then compare the 10 series utility tractors being subpar when compared to the row crop tractors. JD Cooperate knew they had an issue with the utility tractor line. The "blame" landed on the Dubuque engineering department. So when the "new" JD utility tractors where being designed the Dubuque engineering department got the cold shoulder treatment so to speak.

All of this is from years of talking with my friend. HE should have been in the "know". When he retired he was the number two man in the engineering department in Dubuque. He always felt that JD cooperate laid the blame for the 10 series problems on the Dubuque Department only. Never mind that JD cooperate did not give them the time or money the row crop guys had in Waterloo, to design a 10 series utility tractor.

So here is what he felt happened with the entire utility tractor design and manufacturing. When the draft proposals of the 20 series utility tractor where presented to JD cooperate, the Mannheim design proposal was chosen over the Dubuque one. Then both departments worked on the final design. Here is where he was kind of bitter. He claimed that an idea/change out of the Dubuque department was rarely seriously considered. The Mannheim department's ideas faced less resistance.

You need to understand that the utility tractor market was larger over seas than it was here. JD cooperate talked about moving the utility tractor manufacturing over to Germany when the 20 series came out.

So it is NOT just one feature that was US or Mannheim. Its just that the JD, 20 series through the 55 series, utility tractor was mainly Mannheim controlled/influenced.

I have always maintained that the JD utility tractor was not in the league of the row crop tractors. The JD utility tractors always had a complicated hydraulic system that was a real pain to repair when something went wrong.

I got the idea although it might have been incorrect that you stated that the JD utility tractors got their hyd's design from Mannheim from your statement on 08/30/14 & I'll quote you.
Posted: Sat Aug 30, 2014 10:37 pm
Post subject: Re: Looking At A JD 1020, ???'s
Reply to specific post Reply with quote

[/quote]

If Mannheim designed the tractor would not that indicate by your statement that you implied Mannheim influenced the hyd's?

I do agree that JD utility tractor hyd's are not nears as dependable as the rowcrops and are much more difficult to diagnose when they have a problem.

All I'm striving to do is keep the tractor/equip.info posted on this site as correct as possible.
Thanks for your explanation,Jim

(quoted from post at 14:12:19 09/04/14) JD Seller
This is what a US patent search revealed. I saw no mention of Mannheim,Germany although I suppose Mr. Van Gerpen Waterloo,Ia could have been a German.
Jim
https://www.google.com/patents/US2892311?dq=closed+center+hydraulic&hl=en&sa=X&ei=zzQGVJLoMYeQgwTwpIFo&ved=0CC0Q6AEwAg

Click to expand...

To simplify . Waterloo/Dubuque received the excellent 300 series engine from Mannheim/Saran. Mannheim received the closed Center Waterloo hydraulics.
I still maintain that many so called Mannheim/Dubuque utility tractor problems were due to lacking or shoddy maintanence by the owner or operator. Or incorrect hydraulic connections. We still have people here that think returning hydraulic oil direct to the transmission sump is acceptable for high flow loads.

I agree with most of that generally...
What I would add... my opinion of the Manheim CC hydraulics is not that high for the simple reason that the layout of that system was not too bright to begin with. You install a charge pump with less than half the rated capacity of the main system pump and then wonder why you have cavitation issues... not that bright in my books. Relying on return flow through the charge strainer to make up for the nonexistent charge flow is about the cheapest trick I ever saw in a tractor hydraulic system...
There's some of them around here that have the return plumbed into the strainer and they're still nightmares.

Rod

For what it's worth I don't see anywhere in that statement where it says anything about the origin of the CC hydraulic system, Manheim, Dubique, Waterloo or otherwise.
What I do see is a suggestion that one not tackle diagnosis on a Manheim as their first foray into Deere hydraulics. That is perhaps sound advice... I would say that would depend on the individual and their general CC hydraulic knowledge to begin with along with their ability to read and ~comprehend~ the service manual...

Rod

WOW- reading comprehension! That's a problem. You remember me asking about scrapping my steel "Budd" rims a day or so ago- one post asks- "steel or aluminum"?

I noticed that...
I think it's one of the larger problems on this forum sometimes.

Rod

(quoted from post at 12:24:49 09/05/14) For what it's worth I don't see anywhere in that statement where it says anything about the origin of the CC hydraulic system,

Rod

Click to expand...

Rod
Maybe my reading comprehension is not the best especially as good as some members of this forum BUT this is the statement I read and was quoting.

""The hydraulic system on a JD Mannheim designed tractor, is NOT the place to learn to work on JD hydraulic systems.""

You can construe it how ever you wish.
IMHO Ford's CCLS system isn't much better if in actuality it is better!!
Jim

The Ford system has plenty of idiosyncrasies... no doubt about that. It's somewhat cheaper to fix tho.... and be fairly confident it is fixed when you're done vs hunting for leaks of unknown origin.


Rod