ARB leak help
 

So I did a search but didn't find much. I had an ARB rear locker installed in my '96 4x4 4Runner a few weeks back. My compressor turns on every 30 minutes or so when engauged. That's keeping the locker on, not turning on and off. Is this normal? It seems quite excessive. I would think once every few hours or so at most. Oh and its an ARB compressor with only 1 locker attached.
Thanks

you've got a small, slow air leak somewhere. turning on once every 30 minutes of continuous engagement isn't bad and pretty typical for a good install. if it were every 5-10 minutes, then i'd start to worry...

Maybe I have a really good install but I can let mine sit for hours before it'll turn on. Every 30 minutes wouldn't worry me much, but it'd be nice to figure out where it's leaking.

That's pretty normal with the ARB setup. Mine is about the same. No worries mate.....

Like they said 30 minutes is nothing to worry about... But it is worth checking the fittings on the compressor and diffs with some soapy watter for leaks as it is easy to fix if that is cause. I had a hard time sealing up the compressor fittings when I installed the airup kit, ARB recomended a certain type of liquid sealer that seemed to do the trick.

Thanks everybody. I think I'll try to find what ever small leak(s) I might have and go from there.

I don't think you have a leak. If you look at the ARB install instructions you will see that 30 minutes between cycles is what ARB says is the minimum time to shoot for during the final post-install test.

yikes 30 min.! mine goes on about every 15..... thought that was normal.
sorry to hi-jack but it looks like my ARB compressor is leaking oil?? not a ton but a fair amount compared to the size of the thing. it still works fine. any suggestions? anyone have this before

Is it coming from the compressor itself or one of the solenoids? My rear locker solenoid pukes gear oil everytime I disengage. The only thing I can figure is that my air line was nicked when the diff was pushed into the housing or I have a problem with one of the o-rings in the locker. Everything works the way it should, it just makes a mess under the hood.

I don't think the ARB compressor should recycle every thirty 30 minutes - I say you have a small leak. 95% of the time it's going to be at the can, 4.9% at the solenoid/compressor fittings and .1% of the time it'll be seals within your differential. (My figures/my experiences) Soapy water will tell you quickly if it’s the solenoid/compressor. If you've been off-road a lot in dusty conditions take the can off (bolt on back of can unscrews) and remove the 0-ring very carefully, clean the o-ring grove on the can and mount - dress the o-ring with an o-ring dressing (I use a Teflon multi-purpose lubricant) and replace the o-ring and remount the can and tighten good and snug. That will normally do it for most folks. You'll probably have to do this every two years; at least that's been my experience. If a solenoid fitting is leaking Teflon tape will cure that.

If the solenoid is puking gear oil you may find that someday your locker won't engage and the compressor will keep running. Just take it apart. If you've never done that before here’s how:

First make sure no power is going to the solenoid. You can either remove the fuse to the solenoid or unplug it from the connector. On the top of the valve where the electric coil is, you’ll see a round black crown looking piece (it is about the diameter of a dime). Unscrew it and then you can slide the coil off the spool. (You want to make sure there is no power going to the electric coil before you remove it. If you remove it from the round spool (shaft) while power is applied to the coil, it will fry it in a New York second. If it is unplugged it’s fine, just don't power up the coil without the spool being in place, because it will go titts up upon power being applied because it has something to do with the inductance and how it collapses the magnetic field or something like that.) (On the trail when this has happen I just turned off the truck and went to it and didn’t bother with the precautions and so far so good) With the coil off you will see 2 Phillips screws. Remove both screws with a #1 Phillips screwdriver. Pay attention to the mounting plate orientation (if you have 2 lockers and you mess up, you’ll always be able to take the other one apart to see how everything goes together – one locker, either carry a spare or don’t mess up). Then grasp the aluminum base with one hand and use the other hand to pull the spool outward while wiggling slightly. Be careful not to pull to hard because there is a spring underneath and you don’t want to lose it. With the spool out, check the inner 2nd spool by sliding it out. Inspect all parts and clean with contact cleaner if you carry it, otherwise wipe it off real good. (You may notice a light film of gear oil in the area – this is not common but it’s why you’re taking this damn thing apart. Just clean it off real good and make sure the o-ring and seat is clean and it’ll be fine until next time you force gear oil up the line.) Pay close attention to the o-ring and the rubber seat on the end of the 2nd spool. After cleaning and before assembly spray the spool and seat with WD-40 if you have it and then carefully push the spool into the base - wiggling it slightly helps to seat it without pinching the O-ring. While holding the spool down carefully install the mounting plate and 2 screws. Slide on the coil and thread the coil nut back on. Hand tighten the coil nut carefully since it only needs to be finger tight but most of us torque it down a little.

This gear oil problem is caused by 2 things that I'm familiar with - semi plugged diff breather or the diff breather is on the small side. Some drill and tape the breather hole to 5/16, some clamp a larger diameter hose to the breather fitting. I know a larger hole works, not sure about the larger hose. What's happening is when pressure builds up in the differential the breather tube isn't adequately handling it and your airline then tries to assist. I didn't figure this out on my own, Tim at ARB enlighten me.

Hope this helps someone.

:good: Thanks Joe. I need to rebuild my soleniod as you described. Mine pukes oil all over and I thought this was due to a bad o-ring inside the diff. I had this same problem shortly after it was installed and I took it back and they had to take the diff apart to fix it. Also, my compressor cycles about every 5 minutes. I have never had a problem with the locker disengaging so it must maintain an adequate amount of air pressure to the diff even with the leak.

My problem must be in the diff and until I get that done I won't mess with the solenoid rebuild. Hopefully Cheese can help with some locker-rebuild love at Slee when I get to Colorado. I do carry a trail-spare solenoid just in case the oily one dies.

I had to have a leaky o-ring and u-seal replaced this spring. Took the shop 3 damn months to do it as a bench job. Part of the problem was that the diff wasn't shimmed right, so the loading and unloading ended up machining down the thinner ARB-specific bearing, created all kinds of slop and took the ARB from needing to be warmed up before I engaged it to not engaging at all. Most of the wait -at least as reported to me- was that ARB was seeing more of this lately and having trouble keeping those seals on the shelf. Mine's an RD89, not the same as for a Runner, but if the seal supplier changed something around the time ours were built, I'd not be surprised if you were looking at the same thing, especially if the installer just slapped it in carrier for carrier and didn't spend time making sure the R&P was still set up right.