Welcome! Please use the navigational links to explore our website.
PartsASAP LogoCompany Logo Auction Link (800) 853-2651

Shop Now

   Allis Chalmers Case Farmall IH Ford 8N,9N,2N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver

Crawlers, Dozers, Loaders & Backhoes Discussion Forum

JD 450c hydraulic question

Welcome Guest, Log in or Register
Author 
jmartin

01-07-2004 06:30:57




Report to Moderator

Have a 450c crawler loader. The bucket will roll forward (drift) after the hydraulic oil warms up, even without any weight in the bucket. I have tested to see if the bucket will drift in the oppiste direction using the weight of the machine, tilting the bucket forward and lowering the arms to the point where the front of the machine is off the ground, but it will hold position. It seems to me that I might have a bad o-ring on the relief valve for the lower side of the rolling(tilt) cylinders. I don't think it is a bad o_ring in the cylinders themselves because it only drifts in one direction. Anyone have feedback on this?

[Log in to Reply]   [No Email]
Mike

01-09-2004 21:42:03




Report to Moderator
 Re: JD 450c hydraulic question in reply to jmartin, 01-07-2004 06:30:57  
Is it possible that one of the piston nuts came loose? Pull the pins that pin the rod ends of the cylinders to the bucket and see if you can pull the rods out of the cyls.



[Log in to Reply]  [No Email]
jim/pa

01-07-2004 09:25:43




Report to Moderator
 Re: JD 450c hydraulic question in reply to jmartin, 01-07-2004 06:30:57  
the cylinders dont have just 'o' rings, they have seals also, one set for each direction of travel. it is possible that you have a bad set in one or both cylinders, but more likely the problem is in the valve. good luck



[Log in to Reply]  [No Email]
jdemaris

01-07-2004 17:59:55




Report to Moderator
 Re: Re: JD 450c hydraulic question in reply to jim/pa, 01-07-2004 09:25:43  
You've got me a little confused with the " sets of seals for both directions" you mentioned. Maybe you've seen something I haven't, but I was a Deere mechanic for a long time. All that I've seen, new or rebuilt (on the Deere 450 series) used Chevron packings - one set/stack per cylinder piston and one set/stack for the rod. Regardless which way they are pointing, they seal in both directions when they're not blown. Unless you're talking about each separate segment in the Chevron stack? We were advised by Deere company to install the stack with all the "v"s facing out when rebuilding (to avoid cutting them or flipping them over). Very common for a few in the stack on the piston to be worn or blown, and subsequently, the bucket will curl down on its own. I just had to repack my bucket cylinders on my 1010 loader because it was doing the same thing. If the packings are frayed a bit, make sure you clean out the steel-mesh suction hydraulic filter that is hiding under the oil at the bottom of the hydraulic tank (I don't mean the throw-away return filter on top).

[Log in to Reply]  [No Email]
jim/pa

01-08-2004 12:07:48




Report to Moderator
 Re: Re: Re: JD 450c hydraulic question in reply to jdemaris, 01-07-2004 17:59:55  
in the stack of chevron packing rings, you'll find an equal number facing in opposite directions. the direction they face, i.e. the side the flare is on, is the side they seal. if all are installed in one direction, high pressure will cause blowby in the other direction. there is no need to install all in one direction anyway, due to the flare at the end of the tube, use to compress the packings as they are installed. if there is scoring, in my experience, it involves all rings, therefore it affects both directions of travel. it is very common to have scored rings, or ones so old that they no longer flare, in this case the cylinder will normally still operate, but with reduced lifting capacity, and usually audible blowby. my suspicion of the valve, is not necessarily centered on the relief valve. the first step in troubleshooting, would be, is the valve centering mechanically? after that i would make sure that the springs, detents, and spools are all in good condition, as it sounds to me as if a spool is leaking by, very slowly. good luck, jim

[Log in to Reply]  [No Email]
jdemaris

01-08-2004 12:48:44




Report to Moderator
 Re: Re: Re: Re: JD 450c hydraulic question in reply to jim/pa, 01-08-2004 12:07:48  
Okay, appears we're talking about the same thing. Guess my experience has been a little different than your's. A lot of my repair work was on the road - in the woods or at the jobsite. Had many occasions when it was too cold to chance sticking any Chevron style packings into a cylinder unless they were facing out - even with the starting-chamfer at the end of the cylinder barrel. They're not very pliable at 0 degrees F. Had the same sort of trouble with log skidder steering cylinders also, but they used once piece teflon rings instead of Chevrons. Anyway, in 30 years, I've never experienced a cylinder that leaked internally because the packings all faced the same direction. But, anything's possible, I guess. I recently had a problem on one of my dozers (Allis HD6) because the blade kept settling down. Pulled the cylinders apart and was suprised to find out all it uses on the pistons is a single o-ring and backup washer. Later found out my HD4 is the same way. Makes me appreciate a little more the way my Deere and Case are put together.

[Log in to Reply]  [No Email]
jim/pa

01-08-2004 14:09:49




Report to Moderator
 Re: Re: Re: Re: Re: JD 450c hydraulic question in reply to jdemaris, 01-08-2004 12:48:44  
i have a skidsteer with the same type of cylinder packings, 1 'o' ring, with a backup on either side. theyre ok for small cylinders, but the major drawback that i've seen is if there is any misalignment, like a slightly bent ram, those 'o' rings will blow apart in a heartbeat. i did quite a few cylinders outside too, in quarries, and out in the woods. i always had a propane torch, and a #10 can handy to warm up those seals, also takes alot of lube to start one in the cold. im really surprised that you never had any trouble reversing seals though, it seriously compromises the the lifting ability of the cylinder. i worked mainly on cat's tho, with cylinders in the 12-18 in. range. and no i didnt get those seals in the #10 can, that was strictly a shop job, due to the 5000 ft/lbs of torque on the piston retaining nut. i have to say that i have enjoyed reading your comments, you are a very knowledgable fella, and i've learned much from you in the past. its great having an ex deere mechanic on the board. i think you said before that you're in n.y. state, im just south of ya, in north pa. thanks again for all of your knowledge and help, jim

[Log in to Reply]  [No Email]
jmartin

01-07-2004 19:20:47




Report to Moderator
 Re: Re: Re: JD 450c hydraulic question in reply to jdemaris, 01-07-2004 17:59:55  
JDEMARIS, If the problem is in the cylinder wouldn't bucket drift back if left under pressure(bucket tilted forward 45 degrees loader arm all the way down set for a day did not move)? The cylinder rod packings are not leaking, but I do have a slow leak around the valve. I am thinking it is the relief valve O-ring. Thank You



[Log in to Reply]  [No Email]
jdemaris

01-07-2004 20:32:54




Report to Moderator
 Re: Re: Re: Re: JD 450c hydraulic question in reply to jmartin, 01-07-2004 19:20:47  
I guess anything's possible. I'll have to look at the control valves on my own Deeres tomorrow and see if there is a relief valve for the bucket curl. A lot of the Deere open-center system crawlers only had one main relief valve, not separte circuit relief valves for each function as you'd find in later machines. Usually a threaded stud sticking out with a jam nut and a cap over it. It's a lot easier just to look at it then overthink it. Going by your thoughts, you'd have a separate circuit relief valve for bucket-curl-down function only. I've seen that sort of discrete valving on backhoes and skidsteers. Deere usually wasn't so concerned about separate circuit pressures on the early crawlers, though.

[Log in to Reply]  [No Email]
[Options]  [Printer Friendly]  [Posting Help]  [Return to Forum]   [Log in to Reply]

Hop to:


TRACTOR PARTS TRACTOR MANUALS
We sell tractor parts!  We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]

Home  |  Forums


Copyright © 1997-2023 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy

TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters

Website Accessibility Policy