Hydraulic advise needed for JCB 3CmkIII

[MichgaelSC]

Hello people of CMN

I am excited to write my first post and to (hopefully) tap in to the vast knowledge pool present on this forum.
So my girlfriend and I bought Randi the backhoe (the previous owners daughter had named it so) a JCB 3C mkIII for jobs around our house. We did not have a vast amount of money to buy one, so it is somewhat in a sorry state. You get what you pay for, obviously... The previous owner had it for 7 years and hasn´t done any servicing in that time! I aim to rectify this somewhat, and first on my to do list is to change the hydraulic filter, fixing leaks and to top it up.
As mentioned, funds are an issue so i am keen to safe money were it is possible. The workshop manual specifies that only "special" JCB hydraulic oil should be used! Is this necessary or are other products viable? And which ones? At work i can source some Shell Tellus T 32 maby even T 46, is this a viable hydraulic oil? Last question is, if it even is reckomendet to mix hydraulic oils? Replacing 190l of oil may be to stretch my source too far and i don´t know what type of hydraulic oil is in the old girl. And before you ask, no i am not stealing, i asked kindly at work if they were willing to help me, which they are
I hope you can help me.
Kind regards
- Michael

[essexpete]

The 46 grade would be best. What is the existing oil like. If it is very milky I would not waste the new oil mixing with badly contaminated old.

[Sn0gen]

Hi
Thanks for the reply
The oil looks good, it is very clear.

[essexpete]

That is a good start.

[MrF]

I have ran my 3ciii for years now on 46 in the hydraulics. I also changed out the oil and fitted a new hydraulic oil filter when I first got it as it was contaminated quite badly, because my machine was also neglected for years. When I extracted the main hydraulic filter it was beginning to break up in places so I was happy I did that though its not a small job emptying and containing all that oil. There is also a strainer to clean out in the bottom of one of the hydraulic tank legs you can service while its drained.

You could drain the oil into a clean container, and if it looks reasonable re-use it and just throw the bottom few cm of oil away in the container after leaving it to settle. 190l is a lot to buy when the budget is tight for sure. I'd also encourage changing other filters before they become a issue as cheap insurance, I wish I had of done that with the diesel filters before finding out that the previous owner fitted empty ones to hide the sludged fuel tank issue which destroyed my injection pump inside. Also the transmission filter is easy to change/cheap insurance if you have the brockhouse transmission.

They are great tools, I bought mine for a house build (that was my excuse to my wife anyway) and I've been living in the house for 9 years and still own it

[MichgaelSC]

Thank you for the reply MrF

I am a bit on the fence regarding cleaning the strainer. It´s more work and the gasket also needs replacing (maby even the bolts) if i deside to that job, so i am a bit unsure if that task is worth doing.
When the hydraulics are done, the next job for sure will be to change the oil and filters on the engine. I´ll probably also replace the bearings while i am at it. I sometimes think i can hear engine knock, but if it´s the conrod bearings or something else that rattles about, i am unsure about. It comes and goes when the engine idles for prolonged periodes. Then again the clock broke at 7460 ish hours, so probably not a bad thing to do anyhow, since it is a relatively easy (i hope) job to do

[MrF]

I always have gasket paper about to make new gaskets which I find increases my desire to open things up but my oil was in really bad state when I took it out, so mine may have needed cleaning more urgently.

Coincidentally I just fixed my clock after years of ignoring it not working, I checked the clock a few years ago by spinning where the cable drive went and the needle flicked so I know it worked inside, but the gearbox on the front of the engine and the drive cable were both broke. But I found both on ebay recently. Also my drive gearbox had fell apart and was a source of a oil leak. FYI If it helps and you find some extra budget I used these parts -
Drivebox
https://www.ebay.co.uk/itm/Leyland-Mars ... T&_trksid=

Cable -
https://www.ebay.co.uk/itm/JCB-PARTS-TA ... T&_trksid=

[MichgaelSC]

Thank you for the link to Ebay. Without it i might not have found the wealth of spare parts there
Old JCB´s are a rarity in denmark, so i was a bit concerned if i would be able to get hold of spares, without forking out a lot of cash.

[Tillywolves]

Thanks for that link... I bought a new cable but the clocks still dont work. Inner core isnt spinning, so must be the drive unit. Didnt even think these would be available anymore..