front auto locker not unlocking

[Mattman]

Picked up a second hand auto locker already fitted to a carrier etc so swapped the head with the one in my truck.

I am having issues with it not unlocking at low speed and it seems to mainly affect right hand turns though that could be my imagination.

I am about to pull the diff head and check the cross shaft to spacer clearance and the cam to cam clearance.

Does anyone know if the clearances being either too large or too small would cause this?

Cheers
Matt

[tallsam66]

Id say stuffed pins & or springs.

[tweake]

you can get a problem with the clearances being uneven. you want the clearance between the crosspin and locker to be the same on both sides of the crosspin. imho thats probably the common cause of stuffed pins/springs.

if clearance is to small it will stay locked all the time.

[Mattman]

Thanks for the replies guys.

Are new pins/springs available?

Cheers
Matt.

[tallsam66]

Thanks for the replies guys.

Are new pins/springs available?

Cheers
Matt.

suzolla can get them message him

[tweake]

which brand/type auto locker is it?

[Mattman]

I think its a Lokka locker.

Won't be able to confirm until after I tear it down.

[Mattman]

All the pins are broken... New set coming from Aussie.

Cheers
Matt

[lax2wlg]

Did they come out w the oil?

[Mattman]

Nope.

I couldn't even see that they were broken but I decided to dismantle it to check clearances and when I went to pull the springs noticed them. They had broken off inside the plates not flush either.

Haven't checked clearances yet.

Matt.

[Mattman]

I just checked all the clearances and its tight.

The side gear/spacer to cross shaft should be 6 to 20 thou and I have 5 on each side.

The inter cam clearance should be 145 to 165 thou and I have 140.

These clearances are very tight - could they be the cause of the broken pins?

Should I get the thrust washers machined 7 thou each to bring the specs to 12 thou and 154 thou?

Any advice appreciated.

Cheers
Matt

[tweake]

you can't have it tight otherwise it simply will not unlock.
i would also allow a bit more to allow for expansion when its hot.

tho i have my doubts that caused the broken pins. with it to tight the locker won't unlock and the pins won't do anything as the halves are not sliding back and forth.
check the clearances is the same on both sides of the cross shaft. if its not the same one side gets pushed by the cross shaft before the other side twisting the two halves and twisting on the pins.

also check that it needs shims. i think its the aussie locker where some models don't use the shims.

[Mattman]

Thanks for the info. Both sides are identical clearance wise.

How tight should the cross pin be inside the two cam sections? The openings in my cam sections are slightly ovalised.

Would this allow some slight rotational difference between the two sections that could break the pins?

Matt

[tallsam66]

The openings in cam sections are supposed to be slightly oval...if they weren't locker wouldn't ever lock.

http://www.youtube.com/watch?v=kL0hPEOStGk

[Mattman]

Of course...

[tweake]

How tight should the cross pin be inside the two cam sections?

the distance between the two halves should be a minimum of the depth of the teeth on the locker. for it to unlock one side has to be able to slide over

[Mattman]

Locker is refitted and working perfectly. Can't hear it and steering has only marginally changed. Massive improvement.

I had to get 7 thou machined off each thrust washer to get the clearances correct and all the pins were broken so I replaced them.

The crown wheel bolts had been over tightened and half of the bolts were damaged. I replaced them and chased the threads in the holes.

Thanks for all the advice.

Matt.