POWERFAB 125 WTD. HYDRAULIC OIL LEVEL

[wjhe...@hotmail.co.uk]

What position should the boom, dipper, bucket and stabilisers be in to measure the hydraulic oil level ?   What should it then be at MIN or MAX or in between ?

Also so I have used ISO 32 hydraulic oil instead of the equivalent of shell tellus  37 . Is that a problem ?

[Jim]

When you think about how a two-way hydraulic ram works, the amount of oil contained in it in the open or closed position is the same because as the oil on one side of the plunger increases to move it the oil on the other side has to decrease by the same amount. So it won't make any difference what position the rams are in when you check your oil. Anywhere between the lines will be fine. If it was my machine I would probably fill it to just under the Max mark.

Shell have discontinued Tellus 37.  These days you seem to just get 32 and 46 grade hydraulic oil. 46 is thicker than 32. The difference in viscosity between 32 and 37 is not going to be a huge problem in my opinion. In my experience of old diggers, the main problem is keeping the oil inside the hydraulic system :-)

I hope this helps.

[wjhe...@hotmail.co.uk]

When the piston is retracted inside the cylinder there is less oil in the cylinder than when the piston is pushed and the connecting rod is extended.

The reason is that in the retracted position the volume of the connecting rod is also in the cylinder and therefore this same volume of oil stays in the reservoir tank.

Thus you see different levels in the sight glass as the various cylinders are extended or retracted.

Most if not all manufacturers of diggers and similar hydraulic machines recommend  certain positions for the boom, etc. - usually the end of working day rest position so that the oil level can be checked the following morning.  That is the practice I use, but what is the rest position for a towable digger ?  I was hoping that someone could tell me what powerfab had recommended .

On Monday, 20 April 2020 15:02:05 UTC+1, wjhe...@hotmail.co.uk wrote:

[Jim]

Fair enough, I stand corrected, the ram rod will make a difference to the oil level.

All the Powerfab literature that I have managed to acquire over the years and freely share is on the website. Powerfab went out of business nearly 30 years ago so the old manuals and brochures are the only reference now available.