Track tension ajustment problem -JCB mini digger

[V8Druid]

I would do what you’re doing, then twat the side of the frame with a sledgehammer, preferably with a bit of thick plate in between so you don’t dent the frame. If you get any movement, put a bar behind the idler, then try to lever it forward. As soon as you see movement in either direction, stop and try it the other way. If you can, move the jack to the inside, then try to hit where you currently have the jack with a sledgehammer and drift. Don’t go mad and dent the frame though, or you’ve got another headache.

No easy way round this one, but as soon as it moves a bit, you’ve got it. I wouldn’t be putting heat to it.

on edit, after another look at the drawing, it’s probably no. 4 that’s jammed in the track frame, not the idler bearing supports. Is it possible to get a long bar in to hit the plate where bolt no.6 pushes it? Possibly tap the frame around where n.4 sits while trying to turn the adjuster screw in?

I am wondering if the square plate on no.4 has sat in the same place so long that it’s sitting in a wear groove at the bottom. If this is the case, and there’s access from underneath, see if you can wedge no.4 upwards while trying to move it. I know this is a lot of words, but best I can do from here in civilisation.

if you could get the nut off the end of #4 it would separate the slider from the pusher/tensioner mechanism and if that is your issue the slider would come out, giving you better access to the adjuster/spring assembly ?

 

[Bri963]

No mate, he doesn’t want to be touching that big nut. That’s holding the recoil spring and it won’t end well.

 

[V8Druid]

No mate, he doesn’t want to be touching that big nut. That’s holding the recoil spring and it won’t end well.

I realise that Bri but it'd assist in extracting the slider -- as long as he is aware of what he's dealing with

 

[Bri963]

I realise that Bri but it'd assist in extracting the slider -- as long as he is aware of what he's dealing with

I can’t see a safe way of doing it without a lot of prep and more than a modicum of experience. I wouldn’t advise it. Look where access to the nut is.

 

[V8Druid]

I can’t see a safe way of doing it without a lot of prep and more than a modicum of experience. I wouldn’t advise it. Look where access to the nut is.

already set up for it with the jack in place ... remove the nut with a deep socket and ratchet and wind the jack out/off ... if pressure releases from the jack, start at it with the knockometer

 

[T whiting]

Your at the point of brute force and ignorance big sledge hammer or a pecker on another machine should get it moving

 

[Goodwill Man]

Continuing my efforts, I tried once again to pull out the idler (see photo), but no luck—it still won’t budge a millimeter. To get a better view from underneath, I removed the track rollers. I also unscrewed the bolt slightly, thoroughly cleaned it with a steel brush, and lubricated it, so now it moves freely. This created a gap between the bolt and the pushing plate, ensuring there's no longer any pressure from the bolt. Yet, despite all this, the slider still refuses to move.

Why could this be happening? I’m running out of ideas.

 

[Bri963]

Looks to me like in photo 2, plate (no.4 on drawing) has got pushed up and is wedged partly into the access hole. Can you hit it down? Might let the whole assembly slide out. Of course, it could just be an optical illusion.

 

[V8Druid]

portapower ram in beside the pusher bolt and give it some?
should be able to get circa 5t push out of a small portapower - 10t out of a bigger one, if you can get a shorty ram in there
it sure as hell is stuck

 

[Bri963]

portapower ram in beside the pusher bolt and give it some?
should be able to get circa 5t push out of a small portapower - 10t out of a bigger one, if you can get a shorty ram in there
it sure as hell is stuck

Wish we were closer, Gra.

 

[V8Druid]

Wish we were closer, Gra.

yeh - Godalming area IIRC --- 150mls/3hrs from me
used to have a G/F who hailed from Hindhead and got down that way quite a bit in the late 70s ... nice part of the world

 

[Goodwill Man]

Gentlemen,

Yesterday, I underwent a pacemaker replacement, which has temporarily left me somewhat restricted in my activities. As a result, the repair work on my JCB is on hold for the time being.

After carefully considering all your advice and suggestions, I’ve come to a straightforward conclusion: only extreme force will move that stubborn idler slider. I now need to find a suitable tool, ideally hydraulic, with a pressure capacity of 5T+ that is compact enough to fit in the required space.

I’ll start by checking local hire shops, but if you have any specific recommendations for such a tool, I’d greatly appreciate your input. I looked at Porta Power 10T and it may do the job. I need to find it to rent locally.

Cheers!

 

[Diggerdavey]

Gentlemen,

Yesterday, I underwent a pacemaker replacement, which has temporarily left me somewhat restricted in my activities. As a result, the repair work on my JCB is on hold for the time being.

After carefully considering all your advice and suggestions, I’ve come to a straightforward conclusion: only extreme force will move that stubborn idler slider. I now need to find a suitable tool, ideally hydraulic, with a pressure capacity of 5T+ that is compact enough to fit in the required space.

I’ll start by checking local hire shops, but if you have any specific recommendations for such a tool, I’d greatly appreciate your input.

Cheers!

Speedy recovery and good luck with the tensionsr

 

[V8Druid]

this is the sort of thing but the set I have has a couple of different length rams

Pardon our interruption...

and can't find a set on fleabay that has any shorty rams

 

[bobthebuilder]

can we not get a hydraulic jack on its side ? or is it too narrow?

 

[V8Druid]

can we not get a hydraulic jack on its side ? or is it too narrow?

pretty confined space Bob

 

[Storrsy]

Gentlemen,

Yesterday, I underwent a pacemaker replacement, which has temporarily left me somewhat restricted in my activities. As a result, the repair work on my JCB is on hold for the time being.

After carefully considering all your advice and suggestions, I’ve come to a straightforward conclusion: only extreme force will move that stubborn idler slider. I now need to find a suitable tool, ideally hydraulic, with a pressure capacity of 5T+ that is compact enough to fit in the required space.

I’ll start by checking local hire shops, but if you have any specific recommendations for such a tool, I’d greatly appreciate your input. I looked at Porta Power 10T and it may do the job. I need to find it to rent locally.

Cheers!

Hope your back to it soon. Looking at the pics it's hard to see what is causing so much resistance unless the metal plate/s are actually caught on something. Would have thought a bucket pull and pulley block arrangement against a tree would pull it out otherwise

 

[Bri963]

Daft thought, it hasn’t been welded in place at some point?

 

[muckyman]

We had a case 450 similar problem would not budge found out the wear shims on the rails had expanded with rust jamming it ended up with burning set cutting the shims off but i can not think that a mini would have wear shims

 

[Goodwill Man]

Hello again! I felt much better today after my medical procedure, so I headed back to the yard. I tried using a bottle jack to push the idler slider, but had no luck—there was absolutely no movement. I’ll need to find a stronger tool, though the challenge is finding one that fits in the limited space available. On a positive note, I removed the bolt and gave it a thorough cleaning.