J&S 540 Hydraulics

Hi all finaley nearly got the J&S finished ended up getting the motor rewound thats what the smoke was any way it is all back together and it suns smooth but as soon as you turn on the bed starts to move and the lever wont stay up its like the preasure is high and the lever is stiff. now if i let it run for 30 or 40 minutes it will stop when you press the lever and it parks at the right hand side like it should. thin i press the start lever and off it goes but you can see the start lever pulseing up and down. my question could i have used a hydrolic oil thats a bit to thick or could it be something else?

Thank you Bob

WHAT OIL SHOULD BE USED ? what oil did you use ? Noel.

Iirc it’s 32 weight hydraulic oil. Think I put Castrol Magna SW 32 in mine.

Which lever is giving you trouble?

Dave

I think we used Tellus22 in ours, but it was a long time ago, the only thing that makes me sure is that I still have gallons of the oil in the back of the workshop.

Mine ran ok on iso32. HAve you looked at checking the oil pressure and perhaps adjusting it? Mine was an older model but it had a pressure regulator on the top of the pump.

The J&S recommendation is Vacuoline 1405. That's also ISO32.

iso 32 is SAE 10.

The manual states that maximum hydraulic oil pressure is 120 lb/sq.in (.4 kg/sq.cm). It states that adjustment will rarely be necessary but to use a pressure gauge on the output when adjusting the relief valve. If you PM me with an email address I can try to send you a scan of the relevant pages from the manual if you don't already have one but that is about all it says. There is an illustration of the relevant parts and a hydraulic circuit diagram, if that is any help?

Thank you all for the replies I am going to order some 32 and see if it curers the problem if not I will buy a pressure gauge to check it I have the manual so should not be to hard.

Bob

A major reason for the recommendation of a 'thin' oil is that it is also the way oil. The ways on the grinder move a lot more rapidly than lathe ways!

Hi guys sorry for the delay flat out at work My friend said its Morris Lubricants Triad iso 46 oil so i hope this is the problem i assume 46 is a fair bit thicker than the iso 32?

Bob

i assume 46 is a fair bit thicker than the iso 32?

Yes, 46 is noticably thicker than 32.

The Gildemeister lathes at work use 46 hydraulic oil for spindle gearbox lubrication & the difference in thickness can be seen over 32 (kept for hydraulic top-ups) when decanting from barrel to jug.

Hopefully changing to the correct grade will sort your problems.

Nigel B.

I hope so as well

Bob

Latest update.

Hi all many thanks for all the advice it turned out to be several problems firstly the motor was bad and needed a rewire (not cheap) the 40 oil was to thick ans lastly i had the 2 pipes to the pump the wrong way round they are supposed to cross over (seems wrong to me ) but it is now running great and doing a loverly job so thank you all.

Hi Bob nice to hear that your grinder is working well. So many times we don't hear the outcome of restorations and work done on here.

David