Hitachi EX75UR-5

[Locofitter]

Managed to get the RH track tensioned properly, the LH is another matter. The idler carrier/wheel assy flaps about from left to right. I'm assuming this because the grease nipple is naff - doesnt seem to want to take any grease. So now on the hunt for grease nipples for it.

Spent the day greasing all grease nipples, I dont think its seen grease in many years as it took approximately 10kg of grease across 20 or so nipples, shocking really, can already feel the difference in the controls. Arm ram should be ready for collection on Friday so should be fitted next week some time.

[Muz]

Managed to get the RH track tensioned properly, the LH is another matter. The idler carrier/wheel assy flaps about from left to right. I'm assuming this because the grease nipple is naff - doesnt seem to want to take any grease. So now on the hunt for grease nipples for it.

Just make sure you haven't pumped the piston out of its case, and the grease is just falling inside the carrier assembly which you can't see

[Locofitter]

How would I get in back inside if this is the case? I'm assuming it'll be take the tension off the idler and push it back in towards the machine?
I dont think this is the case though as the track looked slack this morning before the work.

[Locofitter]

Anyone?

[v8druid]

Anyone?

IIRC Muz did a tensioner ram a while back with some piccies .... Muz .. am I right? can't recall where though?

[Muz]

IIRC Muz did a tensioner ram a while back with some piccies .... Muz .. am I right? can't recall where though?

Probably hang on ... nah .. cant find it

How would I get in back inside if this is the case? I'm assuming it'll be take the tension off the idler and push it back in towards the machine?
I dont think this is the case though as the track looked slack this morning before the work.

Now you are in for a shift ... to be absolutely certain , you say you pump it up (it takes grease) and it then goes slack ? overnight or something ?

[Locofitter]

The other track was loose but thats been tensioned (2 finger widths at under the most central roller)

The track which is the problem - Noticed it was sagging on the top side a fair bit, tried greasing it (obviously with track off the ground), and it wasn't taking any grease. Grease was escaping from the grease gun connector.
Picked the crap out of it, then used a ballpoint pen to exercise the ball bearing inside the grease nipple - tried again and i barely got 1/4 of a pump into it. (Had approx 4 to 5 finger widths of play on the bottom) Again, wasnt taking grease through the nipple.
It was when I walked on the top side of the track to start greasing the blade cylinder and rod ends that I noticed a lot of left and right wiggle in the idler carrier. It may be because of the amount of slack?
I have a photo of the position of the idler wheel prior to tensioning attempt on my phone but the forum doesnt support image uploading from mobile devices.

Just to be clear, the left side track is the issue.

[v8druid]

Probably hang on ... nah .. cant find it

IIRC not long after I joined Muz ... if you can search chronologically

[Muz]

The other track was loose but thats been tensioned (2 finger widths at under the most central roller)

The track which is the problem - Noticed it was sagging on the top side a fair bit, tried greasing it (obviously with track off the ground), and it wasn't taking any grease. Grease was escaping from the grease gun connector.
Picked the crap out of it, then used a ballpoint pen to exercise the ball bearing inside the grease nipple - tried again and i barely got 1/4 of a pump into it. (Had approx 4 to 5 finger widths of play on the bottom) Again, wasnt taking grease through the nipple.
It was when I walked on the top side of the track to start greasing the blade cylinder and rod ends that I noticed a lot of left and right wiggle in the idler carrier. It may be because of the amount of slack?
I have a photo of the position of the idler wheel prior to tensioning attempt on my phone but the forum doesnt support image uploading from mobile devices.

Just to be clear, the left side track is the issue.

Ok so it is purely that it wont take grease then, which is a different issue ... well that can only be two things, as you say the nipple is faulty, or the tensioner will not go out any further because it is either restricted somehow, or the piston is stuck in the cylinder. The restriction could be a binding issue inside the frame, as clearly its not meant to be out that far, or it could be impacted muck jamming it, so if its not the nipple you are still likely to be in for a shift .. cos you will need to pull the whole lot out and find out whats going on. This means slipping a track off (just at the idler .. dont take it off at the sprocket) and the whole idler and tensioner assembly pulled out for investigation, not the easiest on an 8 tonner, but dooable by a single human

[Muz]

Just FYI (as you are probably aware) .. nipples can be awkward f*cks sometimes if the profile isnt right the gun wont deliver a shot through it sometimes and similarly, if the gun end is worn it wont connect properly with the nipple and there is no grease input possible. On an 8 tonner to fill a tensioner chamber will require a full cartridge of grease or there abouts , especially when its extended as yours is

[Muz]

IIRC not long after I joined Muz ... if you can search chronologically

Mebbes this one ?

http://www.plantandconstruction.co.u...hlight=tension

After post #10

[Locofitter]

Great, thank you for the help so far lads. It is massively appreciated.

I will do that when the dipper ram is back on, should be on next week sometime as I think its easier to move the track around with the digger than bar it over. Probably be a good idea to put a big bottle jack under the frame of it too, just to be safe.

I assume the idler assy will want to spring out? Or will it just pull out without trying to fire its self through my gut?

[v8druid]

Mebbes this one ?

http://www.plantandconstruction.co.u...hlight=tension

After post #10

that's the one Boyo

[Muz]

I assume the idler assy will want to spring out? Or will it just pull out without trying to fire its self through my gut?

There shouldn't be any tension in it , because you will have taken the grease tension nipple out to release any tension but you cant be sure, in case something has trapped the spring. The coils in that will be about 1/2 inch diameter and the whole spring about 8 inches long, so if its under force, its not to be rekoned with. It is attached to the idler wheel assembly usually, so once the track is off, stand aside, and lever out the idler wheel with a pinch bar, and the whole lot should come out in one go, with the grease tensioner a separate unit.

To start with ... gain some extra slack in the chain, I'll usually remove the tensioner bolt, then jam a large wooden block against the sprocket and rotate the track, this crushes the block and pulls the idler back into the carriage, be careful, as grease will shoot out from the tensioner hole as this happens, (be sure youve taken out the whole bolt and not just the nipple screwed into the end of it ) you only need to do this a little bit to gain enough slack to get the track off. If you do it too much, you will be pushing a rusty old piston back into cylinder which will wreck your cylinder seals and potentially jam the piston in there. Usually the rust is more prevalent at the outer end of the piston, when its older like that, so pushing in a little usually isnt a problem, ofcourse, if its a really high quality bit of chrome work, it might have no rust on it at all !! but I doubt that ..

[v8druid]

Great, thank you for the help so far lads. It is massively appreciated.

I will do that when the dipper ram is back on, should be on next week sometime as I think its easier to move the track around with the digger than bar it over. Probably be a good idea to put a big bottle jack under the frame of it too, just to be safe.

I assume the idler assy will want to spring out? Or will it just pull out without trying to fire its self through my gut?

I'd be putting summat a bit more substantial under the frame boyo ..... like some good solid timber cribbing