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BruceTS
09-03-2007, 10:56 AM
One of the inherit problems with running an ARB airlocker is the potential for o-ring leakage, especially on the IFS front diff. When there is a leak it usually causes diff fluid to puke out the breather tube.

On my rig I have an intermittant leak, but just annoying enough not to teardown to fix, so I decided to add a catch can. Only problem is I wanted one that could drain back into the diff after the locker was turned off and inexpensive.

While at Harbor Freight I found the perfect container, it came off a gravity fed paint gun which was on sale for $9.95. I then bought a barbed airline fitting repair kit. Sorry I didn't take pictures of the build-up, wanted to make sure it worked first. The one end of the fitting was 1/4 NPT, I simply chucked it up in my drill press and took a file to it, turning it down to fit inside the paint gun cup fitting, then took a 4" piece of copper tubing and fitted that inside gluing it all together with JB weld. After the glue dried I drilled a small hole at the base of the tube and screwed the whole assembly into the cup. I used a barbed fitting to splice the end of the breather tube to a 6" hose extending so it reached the cup, instead of replacing the entire line, which would have been a PITA.
The way it works is simple, when the locker is puking the fluid it'll take the path of least resistance, so as the fluid rises inside the cup pressure will blow out the top of the tube, when the locker is disengaged the fluid will drain back into the diff throught the small hole at the base of the tube.
http://bruce.calrockx.com/4runner/misc/catch_can.jpg

As for does it work? yes it started to fill with fluid and drained back afterwards, now to test it on the trail. Eventually I'll have a catch can on all the breather tubes, mainly to prevent spills on the trail in case of a roll over, trying to be environmentally friendly.......

Cebby
09-03-2007, 11:41 AM
That's a good idea! From the looks of that catch can, you can get a lot of fluid in there. How much did you notice getting in there? An ounce or a lot?

reggie 00
09-03-2007, 12:00 PM
Nice.

If you could on the next one a couple of pics. And then throw it in the Wiki.

subscribes

BruceTS
09-03-2007, 12:53 PM
They have a smaller spray gun but it wasn't on sale and would most likely worked just as well. It only filled up about 1.5" before I turned off the locker, but on the trail where it's all articulated out, there's a chance for more fluid transfer. I'll see what happens on the Rubicon in a few weeks.....


20 oz cup
http://www.harborfreight.com/cpi/photos/47000-47099/47016.gif
5.3 oz cup
http://www.harborfreight.com/cpi/photos/46700-46799/46719.gif


I was thinking about using the smaller one in the back, but first they have to go on sale :D
When I do make up the back one, I'll be sure to take plenty of pictures.

Lee
09-03-2007, 06:18 PM
please keep us posted, im likely going the front arb route soon.

BruceTS
09-04-2007, 06:28 PM
im looking into getting a front arb air locker. can you:

1) tell me where you got yours
2) explain the issue with the catch can -- why does the o-ring leak???
3) when you turn your locker on, does the fluid immediately go into the catch can, or does that happen after a long period of time? what if you turn the locker on and off as you wheel all day?

Where I got my locker, can't remember, it's been such a long time ago.

As for the o-ring leak, this goes back to when I first had a leak, after taking it apart the problem was due to the the bearing race that get's pressed into the housing, during installation, the place where the o-ring is located got slightly compressed making it fit tight in the housing. ARB told me it should be ok. The o-ring that was in there was damaged, so I replace it, everything worked fine for about 6 months when it started leaking again. I do have a new seal housing and o-rings, but was waiting for the problem to get worse, it hasn't and it's been several years now. Sometimes it leaks sometimes it doesn't......

I've read over the years about similar problems with fluid puking out the breather, one fix was to add a second larger tube, this seemed to help. My approach just prevents any sort of spill on the trails, especially on the Rubicon where the environmentalist are trying their best to close the trail.

The design of the catch can is to recover the oil and return it to the diff afterwards, so as you engage the locker, if fluid flows it will return after it's turned off. So there should be no issues running it on the trail all day.

Lee
09-04-2007, 07:31 PM
thanks for the answers!