1987 JCB 3CX Sitemaster 2WD

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Re: 1987 JCB 3CX Sitemaster 2WD

Post #31 by Slooby » Sun Sep 13, 2020 11:46 pm

Ok, maybe the output shaft nut isn't on finger tight...plus someone has been in there before made a right old mess of staking the nut to the shaft and there are signs of sealant being applied. I hope they haven't damaged anything, because the manual is quite specific about only applying not more than 1.5lbft of torque to the nut otherwise the collapsable spacer needs replacing. I wonder if my leak is because that spacer has been crushed too much and as a result there's nothing to seal the shaft spline in the bearing and seal? With any luck the 44mm socket I ordered from Amazon arrives early doors tomorrow so I can crack on with sorting out the gearbox.

I need to order some new handbrake pads as the old ones were soaked in oil, and pretty much down to the backplates, I had to chuckle that a stack of washers had been added to the adjuster to get what was left of the pads to clamp onto the disc

The correct steering ram pins arrived on Friday and while fitting them I also took the opportunity to shim all the drag link and ram ends where they sit in the hubs, hopefully in doing that I'll reduce any forces on the bushes in the wrong plane.

I've completed the refurbishment of the front loader controls, which entailed putting a new bush into the main link arm*, drilling out the hole in the bucket lever to take a bush, making up some spacers from copper washers, discovering a new pin for the bucket lever in a 5/16 bolt, crossed drilled to take a roll-pin, new clevis pins, a new rod end and a new UJ. What little slop there is now is entirely in the ends of hydraulic pistons that take the clevis pins, and there is nothing I can do about that.

*I think I went about it a bit cock-eyed in the end, as the generic 'oilite' bush I bought needed a lot of fettling to fit and without a metal turning lathe to hand I had to make do with a woodturning lathe and a file to reduce the OD and some emery cloth wrapped around a piece of copper tube to ream out the centre bore:

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The now bushed bucket lever:

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With it all reassembled:

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I got a bit freaked out by the loader arm lever sticking when you push it fully forward then releasing it made a noticeable 'thunk', I thought it might be catching on something, perhaps there was something wrong with the way I assembled it, or worse; a problem in the distribution block. I checked everything and couldn't find anything wrong. Then late on Friday night, I was reading through the manual to work out which piston it was, before popping a question up on here, when I read a note about there being a detent on the loader control to engage the 'terrain-following' function! :doh:

I mentioned that the seat post has been braced, this is the finished result after a quick coat of paint:

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And back in the cab with the seat refitted too, along with the console for the front loader controls:

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I still need to sort out the drop on the left-hand door and window so I can get them to open and close better, plus fit a seal to the right-hand side window. I also need to lube the runners for the rear window. Once that and the gearbox seal are done I want to get the engine warmed up so I can drain the rather treacle-like oil and give it some nice clean stuff, I fear this engine hasn't had an oil change in a while. I also need to check the levels on the hydraulic reservoir and change its filter, along with the rear diff and slew gearbox oil levels.

Maybe then I can get on and use it for what it was bought for!
CMN Stuff: MF65, Thwaites Nimline, JCB 3CX
Projects: S11a 88" V8 Hybrid, 2 x S111 109"s, Mk11 Mini, Harrison L5A :doh:
Ish projects: T25 Camper, ST675R
Just added: Alpine S5 & Bridgeport Mk2 :wtf:
Sorely Missed: Impreza, E39 M5

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Re: 1987 JCB 3CX Sitemaster 2WD

Post #32 by Slooby » Mon Sep 14, 2020 10:33 am

Aaaaand after another call to Vicary (they are good aren't they!?!) I now have a much better understanding of what goes on with the gearbox output shaft nut and seal. The torque setting of no more than 1.5lbft is a 'Rolling' (which I had read but not understood) figure where the rotational resistance to turning on the thread is measured rather than the clamping force. To deal with the leak I was given the following advice;

Take the handbrake disc off and make sure any wear on the mating face with the seal is dressed as flat and smooth as is possible
put some RTV on the splines where they go through the seal and disc hub to make sure no oil can seep past
When tightening up the stake nut keep going until there is no backlash and a just a bit of resistance

As a precaution I've ordered a new stake nut, and a seal for the rear diff which is the same as the output one on the gearbox. I've also ordered some new handbrake pads and a glass bowl for the fuel filter as mine is missing and has an oversize filter currently fitted to make up for it.
CMN Stuff: MF65, Thwaites Nimline, JCB 3CX
Projects: S11a 88" V8 Hybrid, 2 x S111 109"s, Mk11 Mini, Harrison L5A :doh:
Ish projects: T25 Camper, ST675R
Just added: Alpine S5 & Bridgeport Mk2 :wtf:
Sorely Missed: Impreza, E39 M5

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Re: 1987 JCB 3CX Sitemaster 2WD

Post #33 by Slooby » Mon Sep 14, 2020 11:27 pm

Well today's first mild annoyance was that my new 44mm socket was exactly the same size as the stake nut, I had to use a persuader to get it onto the nut, really quite confused as to what size the nut actually is now a,s at a smidge over 44mm across the internal flats of the socket, it should have been able to go over a 1 3/4" nut as well. Most odd.

Anyway, It didn't take much to loosen the nut off and remove the handbrake disc.

These are the remains of a previous (couple at a guess) attempts to stop any transmission fluid getting past the splines:

Image

The seal that I extracted, using the time old method of drilling a hole, inserting a self-tapping screw and then using the claw of a claw hammer to pull the seal out by the screw head, wasn't particularly hard or brittle, neither was it that worn, it even looked relatively new, which is slightly worrying.

Anyway, this was the sight that greeted me on the inside of the disc:

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As the pic shows there is quite a bit of wear (1mm deep) on the nose where it rests against the outer bearing ball race centre, plus a slight groove on the outer surface where it runs against the lip seal. Offering the disc back up and checking for clearance, removing those 1mm lips would result in the flange running on the seal face. Executive decision made as a new disc = £100 ish delivered the old one was going back on after a clean but nothing more, splines all cleaned up, new seal fitted, old stake nut resized on the linisher so it could fit the socket without a persuader, locking tool made out of a bit of Dexion shelving angle to hold the disc still, RTV applied on disc hub splines, then all reassembled and nut tightened just enough to stop any play before staking in place.

Just need to clean the handbrake mechanism up, refit it and the prop shaft, then top up the gearbox fluid before firing her up to see if it still leaks or not. If it does, then I'll try building up the disc shaft with JB weld before finally giving in and buying a new disc if it still leaks!

In other news, I managed to finally get the left-hand bottom door/window hinge pin out and space them up by 3mm. The door certainly closes much better, I've yet to try the window and see if I can get the catch to work without bending. I need to repeat the exercise on the right-hand door/window lower hinges but they only require a 1mm lift.

So, unless anything untoward happens, I should be using her in anger by the end of tomorrow so I can get the engine oil warm enough to change.
CMN Stuff: MF65, Thwaites Nimline, JCB 3CX
Projects: S11a 88" V8 Hybrid, 2 x S111 109"s, Mk11 Mini, Harrison L5A :doh:
Ish projects: T25 Camper, ST675R
Just added: Alpine S5 & Bridgeport Mk2 :wtf:
Sorely Missed: Impreza, E39 M5


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Re: 1987 JCB 3CX Sitemaster 2WD

Post #34 by essexpete » Tue Sep 15, 2020 12:17 am

You have made some good progress!

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Re: 1987 JCB 3CX Sitemaster 2WD

Post #35 by Slooby » Tue Sep 15, 2020 12:34 am

Thanks Pete, I am trying!

Things would be going a lot faster if I had all my tools to hand, and they weren't being held hostage by the ex...

Really need to get out to the far, far field (it sounds far more grand saying it that way, but in reality, it's a 14.5 acre field divided into 3; so there's the 7 acre bit that is 'the field' which goes up to a footpath bordered by hedges, then the 4.5 acre bit beyond that goes up to a big ditch so that is the 'far field' and then the remaining 3 acres on the other side of the ditch which is the 'far, far field') to carry on clearing paths through the trees so the Tree Surgeons can get in to fell some problem trees. They are pitching up on the 1st October, so I'm rapidly running out of time! If I can get her running in good time tomorrow I will potter about moving some piles of ditch scrapings and bullrushes over to the fire pit which should hopefully get the engine nicely warmed up ready for me to dump the rather thick oil and complete the service I had planned to do on day one!
CMN Stuff: MF65, Thwaites Nimline, JCB 3CX
Projects: S11a 88" V8 Hybrid, 2 x S111 109"s, Mk11 Mini, Harrison L5A :doh:
Ish projects: T25 Camper, ST675R
Just added: Alpine S5 & Bridgeport Mk2 :wtf:
Sorely Missed: Impreza, E39 M5

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Re: 1987 JCB 3CX Sitemaster 2WD

Post #36 by Slooby » Tue Sep 15, 2020 10:06 am

Had a :doh: moment in the small hours

Removing those two lips on the disc to bearing mating face would have made bugger-all difference as to how far in the disc would have gone in, it's already mated against the bearing. It's therefore possible that the disc is already sitting too far in and pressing on the lip seal thus opening up the seal.

So, if I do still have a leak I have a further thing to try; removing those lips and spacing the disc back out by 1mm. It would be handy if the shaft were 25mm diameter as I already have the shims...
CMN Stuff: MF65, Thwaites Nimline, JCB 3CX
Projects: S11a 88" V8 Hybrid, 2 x S111 109"s, Mk11 Mini, Harrison L5A :doh:
Ish projects: T25 Camper, ST675R
Just added: Alpine S5 & Bridgeport Mk2 :wtf:
Sorely Missed: Impreza, E39 M5

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Re: 1987 JCB 3CX Sitemaster 2WD

Post #37 by Slooby » Tue Sep 15, 2020 10:39 pm

You know that trusty adage; 'fix it till it's broken'? Well, today after 3 weeks of sorting out niggles with the machine that had bugged me on its arrival I finally reached the point where I could get in and drive it...but alas it didn't want to play :(

All I had left to do today was refit the handbrake after stripping the mechanism down, giving it a good clean, straightening the return spring and fitting new pads. They arrived at about 4pm so there was a fair bit of hurry up and wait. With the handbrake fitted and adjusted, the prop re-connected and the transmission filter changed I fired the engine up so I could lift the loader arm and get access to the engine bay to top up the transmission and hydraulic fluids. In changing the output shaft seal I'd lost about 2 litres of fluid, and it had barely been on the dipstick when I had checked it on arrival, in all it took about 3.5 litres to top up to the midway point on the dipstick. The Hydraulic reservoir took about 16 litres to top off.

Satisfied with the fluid levels I got back in the cab, fired up the engine with a little bit of hand throttle to keep the idle up, moved the rear boom to the traveling position and engaged the newly fitted boom lock, lifted the loader arm off the safety strut and got out to remove it, then back in the cab, lowered the loader down to traveling position, foot on the transmission dump peddle, engaged first gear, shifted the shuttle lever into forward, foot off the dump and onto the accelerator....nothing...hmmm...oh, handbrake, foot on the dump, shuttle to neutral, handbrake off, shuttle to forward, foot off the dump...nothing...hand throttle? dump on, shuttle neutral, hand throttle off, shuttle forward, dump of, accelerator...nothing... dump on, shuttle neutral, another gear, etc etc etc nothing no movement, same with shuttle set to reverse, nada, zilch :evil:

:arrrrgh:

Now, I know that there is no handbrake switch as the cable is dangling down under the cab with the back end of what was once a switch still attached. There's no seat occupancy sensor.

I know the things does/did drive, I drove it round from next door back to our yard and have shuffled it round a few times.

All I have done to the transmission is change the output shaft seal (which as I mentioned lost about 2 litres of fluid), give the handbrake disc and mechanism a good clean before refitting, the disc with the prop removed was turning the transmission freely enough. I've replaced the transmission fluid filter (and in doing so had to wind the thread out a little bit so it would pick up on the new filter) and topped up with 3.5 litres of fresh fluid (the correct type as far as I can tell).

I am wondering if I have an electrical issue with either the dump or the shuttle lever seeing as I did have to shift the colum shroud to allow me to move the heater tube. Both the shuttle lever and lights/wipers/indicators stalk are a bit slack on the column, and since my fiddling with shroud the indicators and front wiper have stopped working. I am at a complete loss as to why I've got no drive, I'm struggling to see why any of my mechanical fettling could have caused such a problem and, before I start pulling the steering colum to pieces to look at all the electrics, am I missing something obvious? :dizzy:
CMN Stuff: MF65, Thwaites Nimline, JCB 3CX
Projects: S11a 88" V8 Hybrid, 2 x S111 109"s, Mk11 Mini, Harrison L5A :doh:
Ish projects: T25 Camper, ST675R
Just added: Alpine S5 & Bridgeport Mk2 :wtf:
Sorely Missed: Impreza, E39 M5


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Re: 1987 JCB 3CX Sitemaster 2WD

Post #38 by essexpete » Tue Sep 15, 2020 10:50 pm

Are you sure you have not disconnected a handbrake switch? Whatever I reckon you have an electronical glitch. No need to use the dump pedal for pulling away or shuttling.

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Re: 1987 JCB 3CX Sitemaster 2WD

Post #39 by Slooby » Tue Sep 15, 2020 11:25 pm

essexpete wrote:Are you sure you have not disconnected a handbrake switch? Whatever I reckon you have an electronical glitch.


Well the handbrake switch cable was dangling with the remains of the switch attached when the machine arrived as I remember looking at it and wondering what the connector was meant to be attached to.

My gut says electrical gremlin too, as I cannot see why anything I have done to the machine mechanically could've upset the transmission. Urgh... I hate playing with electrics, especially without a decent multimeter...

I did start a thread in the Backhoe section about this too, and pondered there if a poorly charging circuit or battery could cause problems like this, because the charging light came on while the engine was running at tick over just before I gave up and pulled the kill lever

essexpete wrote:No need to use the dump pedal for pulling away or shuttling.


I am most confused by the transmission dump, is it purely there to disengage drive sharpish? Do you need to press it to chage gear even?
CMN Stuff: MF65, Thwaites Nimline, JCB 3CX
Projects: S11a 88" V8 Hybrid, 2 x S111 109"s, Mk11 Mini, Harrison L5A :doh:
Ish projects: T25 Camper, ST675R
Just added: Alpine S5 & Bridgeport Mk2 :wtf:
Sorely Missed: Impreza, E39 M5

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Re: 1987 JCB 3CX Sitemaster 2WD

Post #40 by Slooby » Tue Sep 15, 2020 11:55 pm

And while on the subject of confusing controls; what does the 'hydro-lock, on the the side of the backactor control console do/act on?

Mine seems determined to stay in the 'locked' position (because a piece of hose really doesn't work well as a means for translating a side ways rotation into a horizontal rotation) and i know it rotates what I presume is a valve in the backactor valve body. I thought it would lock out the excavator arm controls, but it doesn't so I am a bit confused to its purpose too.
CMN Stuff: MF65, Thwaites Nimline, JCB 3CX
Projects: S11a 88" V8 Hybrid, 2 x S111 109"s, Mk11 Mini, Harrison L5A :doh:
Ish projects: T25 Camper, ST675R
Just added: Alpine S5 & Bridgeport Mk2 :wtf:
Sorely Missed: Impreza, E39 M5


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