Wizard
SupporterDoubleChevron just got in before me.
Does your selection lever in the cab just flop left to right and back? And or flop to the dash and back to the centre cubby?
Checked the linkage is good?
Part of the diff lock engagement process makes a ball bearing move from one groove to another, with an obvious ridge in between that requires some effort to get the bearing over. You wont see this directly as its inside the box. Ditto with the hi/low, but three 'clicks' hi, neutral and low.
Re the diff lock action. In the disengaged position, gently wiggle the engagement lever back and forth. Movement in my vehicles (Discos and RRC) is about 1cm. This movement expressed through the lever is the accumulated slackness in the linkage and movement around the ball bearing in its disengagement groove. Beyond that movement you should then feel some reasonable resistance in the lever before the ball moves under some force over the 'hill' to the engagement slot. The the lever movement under this force is pretty quick so you might not sense the ball engaging the other slot. And likewise you should also have a similar degree of lever wiggle in the engaged position and similar level of resistance as you return to the disengagement slot.
If you're getting the above feel then linkages for locking are good and the differential lock shaft and its ball bearings is good. The problem then might be a worn/broken selector fork (not a big expense if you replace it your self with a second hand unit). It should be a similar feeling with hi/low.
One other possibility. The ball bearing, mentioned above, is kept at the bottom of its bore hole by pressure applied via a grub screw and spring. If the grub screw has drifted loose there may be no spring pressure to keep the ball in place. In this case you may well be engaging the locking diff, but as soon as you take your eye off it the diff disengages – and this would only be slight movement in the stick in the cab. Provided your grub screw is still in its threaded hole then all you need do is find the right hex key to tighten it up from outside the housing. Over tighten it and you wont be able to move the lever at all. Alternatively some one else has had the box apart and not put the ball bearing back in
Another possibility is a collapsed diff centre. Not good, but would expect maybe some complaint from that area when driving. Never had one collapse so maybe someone who has might like to describe if it it causes any noise after the event. You might be lucky in a collapse that it is just the pins have broken and the gears are recoverable with new pins. I replace my pins with a solid set.
YarnMaster
SupporterI think it was apart just before I bought it as the high/low range wasn't working (loose grub screw on the shaft). It would be really bloody easy to drop a bearing ( Yeah I haven't done that before
seeya,
Shane L.
Wizard
SupporterBy your comment that you were going to pull it apart anyway sounds like you can swing spanners when needed, so your probably across the basics already.
Both the hi/low shaft and the locking shaft have ball bearings to give the notchy feel as you move the levers. Both systems have grubs with springs to apply pressure and both grubs can be adjusted from outside the case at different locations.
As there are grubs for the spring loaded ball bearings there are also grubs for the selector fork but no springs, just like when you want to attach a pulley to an electric motor you wind down a grub to engage the flat on the shaft. So yes, a loose grub on the hi/low selector fork will do it for the hi/low.
From memory the diff lock selector fork has a different arrangement for holding it on to the shaft ie a spring holds it in place allowing a little movement, no grub.
You say the box was apart before you bought it, and the guy/gal highlighted the hi/low repair issue, so its safe to assume they are honest and that the diff centre is probably OK. Little point in fixing the hi/low issue otherwise
There are two other issue with the ball bearing/spring/grub system used to ratchet the shafts. They are fairly obscure.
I forget which way about it is, but the grooves on one shaft are quarter inch and on the other shaft they are five eighths. You would expect a quarter in ball bearing for the quarter inch grooves and five eighths ball for five eighths grooves. But I found five eighths used in both grooves. It meant that the five eighths ball would not fall into the quarter inch groove and gave poor engagement ie popped out.
Invariably as you open your casing a ball might fall out. So you put it aside to be re-enstated near the end of the job. Your casing is all now back together, maybe even back onto the gearbox. Ahh, that ball bearing! So from outside the casing you take out the grub with a hex key, and remove the spring with a magnet. You pop the ball down the hole, followed by the spring and then the grub. You then spend a frustrating time trying to adjust the grub to get ball bearing engagement with no success. On re-examination you find the ball jammed at what seems to be the bottom of the bore hole. Seems the hole is either tapered with another chamber further on for the ball, or miss drilled. So what I did before putting the casing back together was to leave the grub and spring in place and re-instate the ball into its hole from inside the casing just before you re-insert the engagement shaft.
How many kms on the vehicle? I ask because you may need to check your thrust washers in the diff. And if you are in there consider replacing the two pin bearings with a solid unit.
Cheers.
YarnMaster
SupporterThere about 19x,xxxkms on it... I tend to trust this as it has service history upto 170,000kms ... at which point is was used as a farm hack. Yep I trust the person that did the work on it .... but hey, **** happens and it's a 28 year old 4wd.... People that buy old cars then complain give me the ****s. If I find problems, I just fix 'em and I know it's then fine for the futureOriginally Posted by workingonit
By your comment that you were going to pull it apart anyway sounds like you can swing spanners when needed, so your probably across the basics already.
Both the hi/low shaft and the locking shaft have ball bearings to give the notchy feel as you move the levers. Both systems have grubs with springs to apply pressure and both grubs can be adjusted from outside the case at different locations.
As there are grubs for the spring loaded ball bearings there are also grubs for the selector fork but no springs, just like when you want to attach a pulley to an electric motor you wind down a grub to engage the flat on the shaft. So yes, a loose grub on the hi/low selector fork will do it for the hi/low.
From memory the diff lock selector fork has a different arrangement for holding it on to the shaft ie a spring holds it in place allowing a little movement, no grub.
You say the box was apart before you bought it, and the guy/gal highlighted the hi/low repair issue, so its safe to assume they are honest and that the diff centre is probably OK. Little point in fixing the hi/low issue otherwise
There are two other issue with the ball bearing/spring/grub system used to ratchet the shafts. They are fairly obscure.
I forget which way about it is, but the grooves on one shaft are quarter inch and on the other shaft they are five eighths. You would expect a quarter in ball bearing for the quarter inch grooves and five eighths ball for five eighths grooves. But I found five eighths used in both grooves. It meant that the five eighths ball would not fall into the quarter inch groove and gave poor engagement ie popped out.
Invariably as you open your casing a ball might fall out. So you put it aside to be re-enstated near the end of the job. Your casing is all now back together, maybe even back onto the gearbox. Ahh, that ball bearing! So from outside the casing you take out the grub with a hex key, and remove the spring with a magnet. You pop the ball down the hole, followed by the spring and then the grub. You then spend a frustrating time trying to adjust the grub to get ball bearing engagement with no success. On re-examination you find the ball jammed at what seems to be the bottom of the bore hole. Seems the hole is either tapered with another chamber further on for the ball, or miss drilled. So what I did before putting the casing back together was to leave the grub and spring in place and re-instate the ball into its hole from inside the casing just before you re-insert the engagement shaft.
How many kms on the vehicle? I ask because you may need to check your thrust washers in the diff. And if you are in there consider replacing the two pin bearings with a solid unit.
Cheers.
I'll try to find an exploded parts diagram so I can see exactly what you mean.
Going to pull it apart anywayTime and money .... That's all that slows me. I've love to get a full rubber bush kit and standard soft springs and fit first (though I don't think I've ever seen standard springs for sale, they all seem to be heavy duty or lift springs)... To try and get it to drive and ride like a Rangy should. I'd rebuild the Boge leveller if required (why hasn't anyone anywhere on any of these forums ever rebuilt one
).
First I've gotta stick a new clutch and flywheel in my wifes modern piece of junk, rebuild a carby for my old ID19 that's flat spotting something shocking just off idle, fit some new from lower arm bushes to my CX ...... There's about 30 suspension spheres sitting in a box in my shed that someone is waiting for me to recharge with nitrogen ... and the miliion and one other things to do around the yard first.
I would like the only useful 4wd I have to be a 4wd though when I need it ... not a 2wd that'll get bogged if one wheel ever gets parked in slop(though I must admit, it has amazing amounts of traction even without the CDL locked).
It's all fun right
seeya,
Shane L.
Wizard
SupporterMine still has the Boge unit (working?). I believe the pressurised unit on the Boge presents a danger to the homeshop mechanic. Some guys have come up with alternatives – how well they work I'm not sure. Some just get rid of the unit and put in Disco springs ie they lose the travel of the original RRC springs. Yet to find a commercial enterprise that fixes them. The Boge limits you to about 700kgs load while the Disco for example is around 800kg without.
One other thought about the locking mechanism. If they took the cover off, where the linkage disappears into the casing, then it is possible they did not line up the external links properly with the internals. Still sounds like you best break it open unfortunately.
YarnMaster
SupporterThanks! As for the boge .... I've driven and towed with an '84 Rangie with original soft hilariously ..... well bloody terrifyingly soft springs ... The bloody thing flopped all over the place around corners in a way that would scare the **** out of anyone................ And I thought it was brilliant
I'm not overly concerned about the load limiter. I'm built a regassing jig that can put 1100psi of nitrogen back into the sphere ( a sphere is just a charged accumulator like the brake accumulator on a p38). And every car I've owned since I was 16years old has run high pressure hydraulics for it's suspension and steering at thousands of PSI. So I'm aware of the issues of high pressure hydraulics. I've no doubt a set of cheap 'O'ring seals and a squirt of oil and possibly nitrogen could bring life back to the boge leveller. I should see if I can chase up a dead one someone is chucking out to see if I can pull it down without destruction.
seeya,
Shane L.
Fossicker
Can I watch?
Roger
YarnMaster
SupporterSure .... You hold the end so it doesn't disappear into another suburb, while I release any residual pressure in the leveler
Wizard
SupporterI'll post you back the end (and bits of Roger) if it reaches Darwin
I'd also be liking to know if you have a fix for it.
Wizard
SupporterMe as a kid watching TV, I think it was Peter Wherrett(?) describing two ways a car can deal with momentum when cornering - body roll without stabilisers - sliding/drifting with stabilisers. I guess too much speed and you would be off the road either way. I'm guessing there is more to it.
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