Outer Limits 4x4 Board

i was wondering if any body know what pressure arb lockers run at. i an getting a rear locker but if i can hook it up to my onboard air when i bolt that back on would be good. im going to run a t piece with un pressurised air for tyres and tools and regulate presure for the lockers. do you guy reckon this will be ok or should i get the arb compressor. thanks chris

OBE will be fine. A small storage tank would be worth it as well.
ARB recomend 90psi to operate their lockers.

i read somewhere in the air lock manual that they cant take over 105 PSI

killalux wrote:i read somewhere in the air lock manual that they cant take over 105 PSI

thats good to know i was planning on running 120psi so i wont have to get a special regulator for it. save me some money to

killalux wrote:i read somewhere in the air lock manual that they cant take over 105 PSI

120psi prob won't be very good ...

I was told by ARB that they run at 90psi but the seals can blow out at 110psi so id be carefull or seek more advice.

Also i suggest fitting a over pressure release valve (adjustable) as my ARB pressure switch failed in the closed contact possition resulting in the compressor constantly running and blowing my front diff lock seal.

A $10 valve is cheap insurance !

The pressure switch on my old ARB air compressor for the locker was a 75psi switch.

It probebly switches on at 75psi and cuts out at 90psi.

the arb pressure switch i run on my airtank cuts out at 110 psi and in at about 80

thanks im going to run two line from my tank one unrestricted for air tools/tyres and one with a pressure reg and blow off valve set at around 100 to 105. to blow off. should go alright when i get it going. just one more question i have a sanden with teh oil sump. should i tap it to put a grease nipple in or put an inline oiler and oil separtor in or just top it with oil and regularly check it before trips. thanks chris

Yes I fitted a pressure gauge to the ARB compressor and it comes on at 75psi and cuts out at 90psi.
It would not take much more than 90psi to blow the O ring seal out.

I would put in the inline oiler and separator, that way you have more control over the lubrication system. The compressors need a little more work internally than just putting on a grease nipple.

Like what?

Those questions can be best answered by the techs at Endless air. The compressors are internally modified to handle grease injection. Without modifications, I wonder where the grease goes? Grease does not easily vaporise... Grease also does not flow like suspended oil, so the compressor must be modded to some level to remain lubricated and also not pump the grease straight out the discharge port on the compressor.

air lockers will engage at as low as about 35 psi, I've tested a few different models and they're fairly consistent. never tested the upper limits to see where the orings will blow out but wouldn't like to take them much higher than 110 psi (have bench tested to 110psi but not in a running vehicle) - although the ARB switch cuts out at 110 does it not? or is it 100?

there's no need to run your OBA up to 120psi, is there?

instead of shelling out for endless I'd be looking for a twin-cylinder compressor with integral sump from the wreckers - pick and payless charge around $40 for these guys and there are tons of them down there. spend a day building your bracket, mock it up in MDF and hot melt glue to get it right then go for the steel and welder.