DLTTrekkers-- Thanks for your reply. That was the adjustment I was making (2nd step in rockshaft setup after the Negative Stop Screw adjustment as listed in the manual) when the whole thing starting acting so weird that I stopped because it would not let the rockshaft lever stay in a lower position. Quite frankly, it just never occurred to me to go ahead and turn the screw one way or another to see what would happen. Maybe I'll try that when I get 'er cranked up again.
John Deere 1640 Strange Hydraulic Problem
- Thread starter Jimbo1640
- Start date
I want to thank everyone for their input on this. Tx Jim--you were right, the top had to come off.
After over a month of dealing with other matters here on the farm, was finally able to get back to it. Ordered a Rockshaft Seal Kit, new piston rings, new gasket for the top, and new washers for the Rate of Drop valve. Took the top off and went at it, changing out all O rings, washers, and piston seal, etc. Learned how to remove the valves and found what I believe was the culprit--a small piece of wire or a shaving from a steel washer that was trapped inside one of the valves. This would make sense considering the weird behavior of the hydraulics and the spraying of oil everywhere inside the Rockshaft when the lever was in the down position--the valve couldn't close! I was pleased that the piston showed very little scoring. Anyway, got it back together and it seems to work just fine so far--very reliable. Wish I done the new seal kit when I had the top off a few years ago.
This 1st image is of my jerry-rigged valve compressor--a short piece of 1/2" copper pipe around the valve stem allowing to gently compress with a c-clamp to access the snap ring.
Accessing the snap ring.
The valves removed, showing the replaced parts beside (the new ones were part of the Rockshaft seal kit). Note a small piece of wire near bottom right--that was up in the valve seat preventing the valve from closing.
Anyway--thanks for your help. Cheers!
After over a month of dealing with other matters here on the farm, was finally able to get back to it. Ordered a Rockshaft Seal Kit, new piston rings, new gasket for the top, and new washers for the Rate of Drop valve. Took the top off and went at it, changing out all O rings, washers, and piston seal, etc. Learned how to remove the valves and found what I believe was the culprit--a small piece of wire or a shaving from a steel washer that was trapped inside one of the valves. This would make sense considering the weird behavior of the hydraulics and the spraying of oil everywhere inside the Rockshaft when the lever was in the down position--the valve couldn't close! I was pleased that the piston showed very little scoring. Anyway, got it back together and it seems to work just fine so far--very reliable. Wish I done the new seal kit when I had the top off a few years ago.
This 1st image is of my jerry-rigged valve compressor--a short piece of 1/2" copper pipe around the valve stem allowing to gently compress with a c-clamp to access the snap ring.
Accessing the snap ring.
The valves removed, showing the replaced parts beside (the new ones were part of the Rockshaft seal kit). Note a small piece of wire near bottom right--that was up in the valve seat preventing the valve from closing.
Anyway--thanks for your help. Cheers!
Tx Jim
New Member
Thanks for update. I'm glad I could be of assistance & you got that hyd problem solved.
Jim
Jim
Zebrafive
Super Member
Thanks for the pictures, and copper pipe trick. I hope I do not have to go into my 2030 rockshaft cylinder or valve :thumbsup:
historyan1975
Silver Member
Hi...
There is a JD 1640, 4x4, from 1982, serial number: 428793... Now, I am looking for a new hydraulic pump... but I am confused. The tractor is made in Europe, I suppose it is not made in Spain... In my research, I found two types of pumps: with 23 CM2/min (1,4 Cu.Inch) flow (AR103036, AR 103033) and 12 cm3 (0,7 CU.In) flow (AR103035)... And, I soo that there exist an other type, more exactly 40 cm3/min. flow.....(AR39695, AR90459, AR97872)..
I supose the pump with 23CM2/min. would be good choose for this tractor, but I am not surre... Please, give me an advice....
Thanks, Benedek J.
There is a JD 1640, 4x4, from 1982, serial number: 428793... Now, I am looking for a new hydraulic pump... but I am confused. The tractor is made in Europe, I suppose it is not made in Spain... In my research, I found two types of pumps: with 23 CM2/min (1,4 Cu.Inch) flow (AR103036, AR 103033) and 12 cm3 (0,7 CU.In) flow (AR103035)... And, I soo that there exist an other type, more exactly 40 cm3/min. flow.....(AR39695, AR90459, AR97872)..
I supose the pump with 23CM2/min. would be good choose for this tractor, but I am not surre... Please, give me an advice....
Thanks, Benedek J.
Tx Jim
New Member
What type hyd diagnostics has been performed to determine your tractor needs another hyd pump? .7 cu inch pump has 4 pistons while 1.4 cu in has 8 pistons . Larger 40 cm3 is different body style so would require different fittings/supply tubes
historyan1975
Silver Member
Hi, TxJim... The problem is that - the tractor hydraulic does not lift, in the backside... Soo, it does not have enough oil pressure. This is one of my friends tractor, my own is JD 1020.
He replaced all of the filters, changed the hyd oil with JD HyGuard, changed the little pump in the crankcase... and does still not lift... He measured the oil pressure - it was only arround 100 bars, instead off 170 bar, as it has to be according to the descriptions---- He tried an other, used pump and worked... What other problem could have?
According to your opinion, the AR103033 or AR 103036 pump would be good? It does not wors to be fixed the old one...
All this pumps have 8 pistons?
Sincerelly,
Benedek J.
Attachments
Tx Jim
New Member
historyan1975
Silver Member
Hi,
The suction screen was checked and cleaned, the relief valve not yet, but they will verify it...
I found something new: ex. in morning, in cold, when the engine, the tractor body is cold - the lifting works perfectly... But, when it gets warmer, the lifting is weakens and finally, does not work at all... Ex. he was ploughing and he had to leave the tractor on field until it is not cold again and starts to lift again... AND, it did all these things with the other, used pump... it was ther same problem - in cold OK, when it got warmer, did not work. I mention - the servodirection works also related to the temperature.