ARB RD56 air leak

**cgalpin** · #1 April 22nd, 2012, 04:50 PM

I'm curious if anyone has had the same symptoms and agrees (or disagrees) with my diagnosis. The symptom was that when I engaged my (front) locker, air was getting into the axle housing and out the breather tube [1].

I pulled the 3rd member and hooked up the line to test, and I can tell it's not leaking at the bulkhead fitting, but hear air coming out of the center of the diff. Is it safe to assume it's the two o-rings where the air line connects to the locker and not something internal to the locker?

Oh and does this scoring on the seal housing look bad? I'm hoping not to need to replace this.

thanks,
charles
1. If on a steep incline this meant pumping oil up the line too which then drips onto your cats and starts a small engine fire. Not good.

dave_lucas · #2 April 22nd, 2012, 05:02 PM

Had a newly installed ARB pumping 90wt out of the diff and it turned out that one of the O rings got pinched so sounds like you are on the right track.

Do not know about the other part of your question

JSBriggs · #3 April 23rd, 2012, 09:59 AM

I assume its the Orings. You could PM Tech Tim on pirate he works at ARB and could verify. http://www.pirate4x4.com/forum/member.php?u=19067

Cool scar BTW.

-Jeff

sonoronos · #4 April 23rd, 2012, 10:37 AM

Woah, I've never noticed that scar before...what's the story with that one?

**cgalpin** · #5 April 23rd, 2012, 07:37 PM

Quote:

Originally Posted by JSBriggs

I assume its the Orings. You could PM Tech Tim on pirate he works at ARB and could verify. http://www.pirate4x4.com/forum/member.php?u=19067

Cool scar BTW.

-Jeff

Thanks. I did email him and he replied with a good suggestion of spinning it while testing, but I had already called ARB tech support and re-tested before he replied. ARB's suggestion was to use soapy water which I'm not sure why I didn't think of! As luck would have it, the inner "u-ring" seal is the one leaking. This involves opening her up and replacing one-time use bolts and washer tabs, so I put in an order for 2 sets of everything (including o-rings to be safe) so I have a spare kit.

What's odd is that this is supposedly a rare failure and usually caused by low oil or overheating, which I am quite sure neither has been an issue for me.

Quote:

Originally Posted by sonoronos

Woah, I've never noticed that scar before...what's the story with that one?

Super secret Canadian Land Rover Society membership brand. I'd have to kill you (or make you a member) if I told you.

**cgalpin** · #6 May 3rd, 2012, 09:40 AM

Well I found my air leak. I wish I had dismantled it before ordering parts and waiting for them. I'm not happy about this as this can only be due to it not being assembled properly during manufacturing (it was brand new when installed).

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This is a thrust washer from one of the pinion bearings. There is no way this was ever installed on the cross shaft. It worked it's way out to the inner seal and jammed between the housing and the seal and piston.

jefhuf · #7 May 3rd, 2012, 10:55 AM

I will be interested to see what ARB says and how well they stand behind their product!

**cgalpin** · #8 May 3rd, 2012, 11:00 AM

As am I. I dropped them an email with pictures and will hopefully be able to make time to call this afternoon.

rijosho · #9 May 3rd, 2012, 11:19 AM

don't forget to tell them you're a moderator of an international LR forum - that may help you get some results.

**cgalpin** · #10 May 3rd, 2012, 12:01 PM

Ugh somehow I doubt it. They are already asking questions to try determine if it's been worked on before, and if I was the original purchaser. Sucks that I bought them from someone else (although new) and he is no longer with us to help me...

http://www.defendersource.com/forum/...rb+rd56+locker

**cgalpin** · #11 May 3rd, 2012, 01:42 PM

Quote:

Originally Posted by jefhuf

I will be interested to see what ARB says and how well they stand behind their product

They get an A+ so far. I explained the history and that I am not comfortable repairing it myself - that I'd prefer they go over it and make sure nothing else is damaged and they said no problem. They are even going to let me return and refund me for the seals and o-rings I bought since they are apparently older ones too.

I believe it's just going to cost me one way shipping and some bolts/nuts I have already bought for spares (although I shouldn't need them unless I get another rare internal failure), so nothing to complain about there.