B8200 oil pressure adjustment and control rod

cornus

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B1750, 1600A,B1600
Aug 25, 2015
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ireland
I am putting a 3PL assembly from a B8200 onto a B1600 The B8200 has an oil pressure adjustment screw on the hydraulic cylinder cover. I am wondering if I should change the cover for the original B1600 one which does not have the adjustment. The adjuster is seized and I would prefer not to have to dismantle.

Also, there is some sort of feedback control, via a rod, from the lift arm of the B8200 version to the hyd system. I hope to be able to avoid having to use that as it would take the place of the B1600 control levers which I hope to reuse (they fit the same outlet plate on both 3PL castings).

Finally there is some sort of strike plate attached to the rear of the well of the main tractor housing which I think limits the travel of one of the 3PL lever parts. This has a slightly different part No in the B1600 vs the B8200 lists and I am wondering if that is significant. (only last digit is different).

I would be grateful if anyone can comment on any of these questions.
 

Dave_eng

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M7040, Nuffield 465
Oct 6, 2012
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Williamstown Ontario Canada
I am putting a 3PL assembly from a B8200 onto a B1600 The B8200 has an oil pressure adjustment screw on the hydraulic cylinder cover. I am wondering if I should change the cover for the original B1600 one which does not have the adjustment. The adjuster is seized and I would prefer not to have to dismantle.

Also, there is some sort of feedback control, via a rod, from the lift arm of the B8200 version to the hyd system. I hope to be able to avoid having to use that as it would take the place of the B1600 control levers which I hope to reuse (they fit the same outlet plate on both 3PL castings).

Finally there is some sort of strike plate attached to the rear of the well of the main tractor housing which I think limits the travel of one of the 3PL lever parts. This has a slightly different part No in the B1600 vs the B8200 lists and I am wondering if that is significant. (only last digit is different).

I would be grateful if anyone can comment on any of these questions.

The B1600 is a grey market machine. The B8200 is listed as a North American equivalent.

Some photos showing your areas with questions would help.

The adjustment screw is likely to control the rate of decent of the 3 pt arms so if you have something really heavy hoisted up it does not slam to the ground when lowered.

You need some sort of feedback mechanism to kick the 3 pt valve into neutral once the 3 pt arms reach the top of their stroke. As you have noted, this is usually done with a feedback rod which at one end is connected to the lift arm and the other to the valve.

Dave
 

cornus

New member

Equipment
B1750, 1600A,B1600
Aug 25, 2015
22
1
3
ireland
The B1600 is a grey market machine. The B8200 is listed as a North American equivalent.

Some photos showing your areas with questions would help.

The adjustment screw is likely to control the rate of decent of the 3 pt arms so if you have something really heavy hoisted up it does not slam to the ground when lowered.

You need some sort of feedback mechanism to kick the 3 pt valve into neutral once the 3 pt arms reach the top of their stroke. As you have noted, this is usually done with a feedback rod which at one end is connected to the lift arm and the other to the valve.

Dave
Thanks Dave
I will post some photos over the weekend. The B1600 did not have any feedback control that I could see. i assumed that the rather complex controller on the 8200 was something to do with keeping a harrow or other implement at a constant depth.
 
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cornus

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Equipment
B1750, 1600A,B1600
Aug 25, 2015
22
1
3
ireland
Looking again at the B1600. It does have a leveling system albeit a much simpler one.
Hyd Cyl Head.jpg
The question now focuses on the cylinder head details. Attached shows the two variants on the cyl head.
Also. Main casting on machine seems to be some sort of alloy on the B1600 while the B8200 appears to be steel (painted red inside). I am wondering if this might cause any issues wrt galvanic corrosion. Should gasket get any special treatment?

Thanks again for your advice
 

cornus

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Equipment
B1750, 1600A,B1600
Aug 25, 2015
22
1
3
ireland
Replacement made. 3PL lifting and holding but will not fall under any circumstances. Have removed piston head on expectation that there is some blockage in the valve preventing back-flow. Arms dropped immediately on removal of the head so at least piston is not jammed. Will dismantle the valve body on the head tomorrow. Will be entering unknown territory here so any advice will be appreciated.
 

Dave_eng

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M7040, Nuffield 465
Oct 6, 2012
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Williamstown Ontario Canada
To be clear, the cover with the knob...... the knob controls the lowering speed of the 3 pt arms. If completely closed the arms cannot drop.

Forum lowering speed knob.jpg


Dave
 

North Idaho Wolfman

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You will not get it to work properly unless you use the feed back linkage, that is the reason it's going up and not going down.
 

cornus

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B1750, 1600A,B1600
Aug 25, 2015
22
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ireland
Thanks for all the helpful advice. As the lowering control valve was duplicated on the control block from the original machine, I swapped the covers (for the other one pictured right above) and now all is good. I tool a look at the valve on the problem one. it had been turning freely but it's action did not effect lowering or arms in any position. I stripped it out completely. It did not appear to be blocked. There are two other ports with allen key adjustment on the rim of the part which lead into channels through the head but these are seized. As the simpler part now works, I don't need to get this one working but I am still curious as to reason why it did not work and what the flow logic is in that version.
 

Dave_eng

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Equipment
M7040, Nuffield 465
Oct 6, 2012
5,107
926
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Williamstown Ontario Canada
Thanks for all the helpful advice. As the lowering control valve was duplicated on the control block from the original machine, I swapped the covers (for the other one pictured right above) and now all is good. I tool a look at the valve on the problem one. it had been turning freely but it's action did not effect lowering or arms in any position. I stripped it out completely. It did not appear to be blocked. There are two other ports with allen key adjustment on the rim of the part which lead into channels through the head but these are seized. As the simpler part now works, I don't need to get this one working but I am still curious as to reason why it did not work and what the flow logic is in that version.
You need to heed the advice provided by NIW in post #8. Unless you clearly understand his message, ask more questions.

The feedback rod is what provides the hydraulic system with the details of where the lift arms are at any moment in time and more specifically, when the lift arms reach the top of their stroke.

In the absence of this feedback signal, the pump pressure continues to be directed against the 3 pt lift piston and excess pressure is dumped by the pressure relief valve resulting in excessive heat build up. A prescription for short pump life!

Dave
 

cornus

New member

Equipment
B1750, 1600A,B1600
Aug 25, 2015
22
1
3
ireland
Understood. I had transferred this also from the original broken cylinder along with control levers and fall adjuster. There is a small adjustment needed to allow for the different relative position of the connection to the replacement lift arms which are slightly bigger than original. Thanks again for your help.