Rear Diff actuator rebuild

[Howmanygoes]

So decided to try to rebuild my RDL actuator. I ended up acquiring a spare damaged one via eBay.

View media item 2722The old unit had a cracked casing and the cover plate I’ll fitting (8-10mm gap ( see red ringed areas)

Internally it was filled....
View media item 2710
After drilling out the screws and cleaning the drive gears, the gears in the old unit were undamaged. The faulty eBay unit had broken bushes and a damaged drive wheel. The bushes in the old unit were also ok.

View media item 2714Damaged drive wheel

So bushes swapped and drive wheel swapped
View media item 2713View media item 2712
Tape was just to retain the sprung bushes until the rotor was refitted

Reassembly almost complete
View media item 2715
Finally inserted the pin and tensioned using rotor. (Not sure if this is right)

And done
View media item 2718
On bench testing (blue red and blue wires) motor drives and pin comes out and in... result as funnily enough it didn’t work before (broken bushes and the old one never would). However on connection the the wiring loom, nothing, zip, nada....

Out with tester.
View media item 2720.View media item 2719CDL engaged (box in low) (CDL doesn’t engage when I push the button in High... confused ) orange light on dash shows engagement.

Put tester to blue and blue red inputs in the socket pictured. And turned RDL switch nothing on meter but abs light and second red flashing RDL light comes on....

Any advice where to go next, I also can’t find the fuse box on the RHS... to find the 20a fuse,

 

[Howmanygoes]

So to update:
I found the fuse box and removed, tested and refitted the 20a fuse. it was fine
removed RDL actuator switch (ball switch) this tested fine.
Removed RDL dash switch, tested fine.

I have taken all the glove box out to try to find a relay or module. there is no clicking like with the CDL switch when I turn the RDL dash switch.

Still cant get power to the RDL actuator plug. I have the box in low with CDL locked. any advice please?

 

[Howmanygoes]

Update. I found a few old threads on here and ih8mud that indicates the RDL controller needs to “sense” the location of the actuator drive wheel before it will send power to drive the motor.

A post on ih8mud (see link)
https://forum.ih8mud.com/threads/locking-diff-actuator-timing.588139/

Talks through how to make the alignments, I have struggled to follow it part way through.

I can now get some action to the actuator when refitted, some times it’s movement out. Sometimes it’s movement in. This has all been on turning the key to accessory position. I therefore presume it’s a check status as part of start up and that my alignment is not correct.

Has anyone else gone through this process? Can anyone advise on other alignment techniques?

 

[clivehorridge]

What you’ve done so far is a total transformation, hats off to you for your perseverance

Can’t help with your question, although @Chris might have some guidance on timing...

 

[Chris]

Nah, not really. All my locker issues have been mechanical. Ie scrap or not scrap. Never had an electrical fault. Always been a bit more solid state. What does happen sometimes s that people put the motor back on in the wrong position, then when they connect the plug, the locker is locked when it should be unlocked. I always plug mine in, let it dangle and operate the switch a few time to make sure it's in phase as it were. Ask me how I worked that one out .....

 

[Howmanygoes]

Cheers for replying guys... I think I am almost there, might need to pull the sensor and extend the cable to do some further “bench” testing. Too bloody hot though today.

 

[Howmanygoes]

This is frustrating..... and I think I will have to give up. So close. It works, just can’t get the timing right. On the main drive gear, and every 1 tooth adjustment means taking it all off.....

Actually might be able to do it from underneath.... hmmm I have an idea... I will report back. One of those lightbulb moments.

 

[Howmanygoes]

Well... I admit defeat. I was so close, maybe too close. If some else wants the actuator to play with then they can have it FOC on the basis they write up how to align the main gear terminals so we can all learn.

I’ve bought another one second hand, if this is also shite I will cough up for a new one.

Arse.... lol

 

[clivehorridge]

Boo-hoo

I was hoping you'd post “all sorted”

 

[Howmanygoes]

@clivehorridge don’t want to count my chickens just yet but I think I bloody fixed it....

I have an ECU clicking, a drive motor whirring, a switch that gives constant red light (allbeit removed from housing) and a shaft going in and out on dash switch rotation. Now just need to free up the mechanism in the diff, figure of 8s here I come.... so hope this works.

 

[Chris]

There's not much to free up in the mechanism in the diff really. It's a really coarse engagement. The teeth on either side are around 10mm deep and wide. The reality is that when there is a bit of wind up on the half shafts and you go lock to lock, the rear wheels don't do anything like as tight a track as the fronts. Added to that all the backlash in the splines everywhere, the rear locker can take some shaking loose. It's totally different to the front. Better just raising a wheel off the ground.

 

[Howmanygoes]

@Chris thanks.

I couldn’t get the internal mech to slide on activation. I will try raising a wheel up. At least I can do this at home and not get stuck somewhere in the middle of no where if it doesn’t unlock.

 

[Chris]

Well no, you wouldn't do it's inside the diff. You would be better to fully extend the actuator, put the control rod through into the diff, put that special little bolt in then pull the motor housing back and forth. But truly, you're not going to be 'working' anything and freeing it up. There's nothing really to free up. As long as there is oil in there the only moving part should be lubricated. As far as engage and release is concerned, the two halves of the clutch can't actually stick together. I think I've got one in the garage. I'll try and find it and post a pic. Sliding it back and forth is really not going to make any difference once it's reassembled and you have the motor connected. The important bit is when you re mount the actuator. Leave all the bolts loose and fire the motor finding a point where it will fire and release without binding. If the push pull is slightly off due to the slop in the mounting holes, you'll get the thing locked but not unlocked. You can drive as many figure of 8's as you like. The bind isn't in the clutch it's in the actuator bar.

 

[Howmanygoes]

@Chris. Thanks. It wouldn’t slide by hand with out the actuator attached.

The actuator rod was sliding freely when attached with out the “special” bolt through the internal “arm” so doesn’t appear to bind.

Is there something (a gear or otherwise) that needs to align inside the diff for it to lock. I’ve seen a few other posts that say to drive to get it to engaged but on loose surface.

 

[Chris]

Yes that's what I am saying. Imagine two turrets on a castle. There's crenellations (teeth) on the turrets. Turn one upside down and interlock it with the other. That's what you have. But there's not that many teeth so there a considerable amount of lining up to do to get them to engage. But when they do they're very strong. You need to spin one wheel considerably for it all to line up and if you do have any binding on the rod then there's reduced effort to fire the two together.

 

[Howmanygoes]

Guess what........






I only went a fixed it and tested off and on 5 times...


Oh yeah......

 

[Chris]

Do a little dance... Sing a little song..

Get down tonight!

 

[Chris]

As promised, here's a picture of the internal gubbins to give you an idea. The front locker is a splined sleeve and lines up very easily. The rear one as you can see requires considerable rotation of at least one wheel to align it.

 

[Howmanygoes]

As promised, here's a picture of the internal gubbins to give you an idea. The front locker is a splined sleeve and lines up very easily. The rear one as you can see requires considerable rotation of at least one wheel to align it.

View attachment 159599

Thanks Chris... no front locker for me currently. Just rear springs and timing belt to do. Then I shall enjoy it a little before further work.

 

[Mikeharris1992]

So to update:
I found the fuse box and removed, tested and refitted the 20a fuse. it was fine
removed RDL actuator switch (ball switch) this tested fine.
Removed RDL dash switch, tested fine.

I have taken all the glove box out to try to find a relay or module. there is no clicking like with the CDL switch when I turn the RDL dash switch.

Still cant get power to the RDL actuator plug. I have the box in low with CDL locked. any advice please?

Hi there what was the location of that fuse? I'm having similar issues and I hope it's that fuse !