Hydraulic system

[dannyleloup]

Hello again John,

I'm still trying to understand the hydraulic system manual, especially how the control valve works. Please could you tell me if I'm right

1. As long as there is no effort on the control spring of the toplink, the only way to action the control valve is the lift lever:
- lever up: pressure sent to the jack
- lever in middle position : no more pressure, but jack still compressed
- lever down : jack is depressed

2. If there is an effort applied on the control spring, it moves the control valve in the same way as if the lift lever is moved upward.

3. If there is a strong effort on the control spring, some internal thrusts modify the movement of the fork driving the control valve, so this valve is moving in the same way as if the lift lever is moved downward. It reduces the weight apply on the wheels, so as they can skid and avoid bigger damages.


Also, regarding the subject "hydraulique retour", I still trying to know how it could be possible to use a device like a rear loader, for example, and in the mean while to keep another hydraulic device on the tractor, like a front loader.

A solution could be to put an on/off valve between the hydraulic exhaust and the front loader, so as you can "block" the loader in up position by switching off the hydraulic supply. The problem is that when you want to use the front loader again, the rear loader has to be removed and replaced by one of the following systems we already talk about, in order to fix the drawbars.

I guess there is a "lack" in the conception of the grey fergie hydraulic system, because there is no way to activate the hydraulic pump without feeding the jack driving the drawbars. I doubt there is any accessory that could suppress this problem, unless it is an "internal" accessory valve. Do you have any information about it?

John, I hope you understood a little bit what I tried to tell you, I know that I would have to improve my english!

Read you soon, kind regards
dan

[dannyleloup]

John,
Bruno just made a copy of your email regarding a valve that could shut the oil flow to the ram cylinder off. It's one of the questions I was asking you. So I'm afraid we will wait a long time before finding one! Thank you!
dan

[john]

Bonjour Dan,
Item 1, You are correct.
Item 2, You are correct, then as the implement lifts it stops the movement on the Control Spring and goes from lift to lower, this allows the implement to go deeper and then the movement comes back on the Control Spring and this is repeated over and over which gives us the Depth Control.
Item 3, You are correct. As the implement strikes an obstruction it compresses the Control Spring very hard and immediately releases any oil pressure in the system and this stops the traction through the wheels as there is now no weight transfer.

Usually on any loader there is a valve of some kind to turn off the hydraulic power to the rams (or jacks) it can be a spool valve with a couple of levers or a simple valve with a hand wheel on the top to turn and shut the oil off. This way you can use the rear linkage of the tractor but leave the loader in position on the front, but with the spool valve type you need to stop the oil circulating by using a valve in the feed to the spool valve.
As you say about the problem of when you need to use the loader and isolate the rear linkage that there is no provision for this. I have written a couple of times recently about this and you may remember that we have spoken of a valve that would allow this but that there are non available now which is a great pity. I think we need to give some thought to this problem and as to whether we could make one simply and cheaply. This problem arises because when the tractor was originally designed it was never thought that it would be used for anything but ploughing, it was designed (in the 1930's) to do that and that only, but then they found it was possible to do other jobs with it so more implements were made for it. All these hydraulic problems were addressed in the 35 tractor.
There is no valve made for this purpose that I know of at this time but I would really like to know if one could be made, how about this as a project for you guys? I know a lot of you are very inventive, how about giving it some thought.
Regarding your English Dan, I understood everything you had to say and I wish my French was half as good.....John

Bonjour Dan,
le point 1, vous êtes correct.
Le point 2, vous êtes correct, puis car les ascenseurs d'instrument il arrête le mouvement le ressort de commande et va de l'ascenseur s'abaisser, ceci permet à l'instrument de disparaître plus profond et alors le mouvement revient le ressort de commande et ceci est répété à plusieurs reprises qui nous donne la commande de profondeur.
Le point 3, vous êtes correct. Pendant que l'instrument heurte une obstruction il comprime le ressort de commande très dur et réduit immédiatement n'importe quelle pression d'huile dans le système et ceci arrête la traction par les roues car il n'y a maintenant aucun transfert de poids. Habituellement sur tout chargeur il y a une valve d'une certaine sorte pour arrêter l'énergie hydraulique aux RAM (ou aux crics) que ce peut être une valve de bobine avec un couple des leviers ou une valve simple avec une roue de main sur le dessus pour arrêter et fermer l'huile. De cette façon vous pouvez employer la tringlerie arrière du tracteur mais laisser le chargeur en position sur l'avant, mais avec le type de valve de bobine vous devez arrêter l'huile circulant en utilisant une valve dans l'alimentation à la valve de bobine. Comme vous dites au sujet du problème de quand vous devez employer le chargeur et isoler la tringlerie arrière qu'il n'y a aucune disposition pour ceci. J'ai écrit un couple des périodes récemment à ce sujet et vous pouvez vous rappeler que nous avons parlé d'une valve qui permettrait ceci mais ce il y a non disponible maintenant qui est une grande pitié. Je pense que nous devons prendre une certaine en considération ce problème et si nous pourrions faire un simplement et à bon marché. Ce problème surgit parce que quand le tracteur a été à l'origine conçu on ne l'a jamais pensé qu'il serait employé pour n'importe quoi mais labourant, il a été conçu (dans les années 30) pour faire cela et que seulement, mais alors ils l'ont trouvé étaient possibles pour faire d'autres travaux avec lui ainsi plus d'instruments ont été faits pour lui. Tous ces problèmes hydrauliques ont été adressés dans le tracteur 35. Il n'y a aucune valve faite à cette fin que je sais de actuellement mais je voudrait vraiment connaître si un pourrait être fait, comment ceci comme projet pour vous des types ? Je sais que beaucoup de vous sont très inventif, que diriez-vous de lui donner une certaine pensée. Concernant votre Dan anglais, j'ai compris tout que vous avez dû dire et je souhaite que mon Français ait été demi en tant que bon.....John

[dannyleloup]

Maybe your french is not so good, but your knowledge about the fergie is not bad at all!

You can come to see me any time in french riviera, it will be a great pleasure to give you some french lessons! If you come during the next two months, you will see my fergie cruising all around my olive trees, it's the harvesting period!

[john]

Bonsoir Dan, that does sound very nice right now, it is freezing here at the moment and it is not going to get any better. The picture I have in my mind of Olive trees and harvesting and driving around on a Fergie is wonderful it is much better that frost and rain any day.....Regards....John

Bonsoir Dan, celui retentit très gentil en ce moment, il gèle ici à l'heure actuelle et il ne va pas aller mieux. L'image que j'ai dans mon esprit des oliviers et moissonnant et conduisant autour sur un Fergie est merveilleux il est bien mieux ce gel et pleut n'importe quel jour.....Regards....John