AirCon Compressor Poll

[HoSS]

Having seen few discussions pop up over aircon pump on-board compressors over the years, and being about to either finish mine, or buy a leccy compressor... I would like to make a poll to collect some real world experience.

Its often discussed if they should be run with oil, or dry with some grease.

It could be useful...

[Orgasmic Farmer]

I have gone one better! I run mine with an auto oil feed in the inlet tract (pipe coming from top of snorkel) and I have drilled and tapped the plug in the top of the compressor and fitted a grease nipple. Whenever I have the bonnet off I give it a quick pump of grease too! Been on there for 3-4 years and is used pretty regularly

[twizzle]

I have gone one better! I run mine with an auto oil feed in the inlet tract (pipe coming from top of snorkel) and I have drilled and tapped the plug in the top of the compressor and fitted a grease nipple. Whenever I have the bonnet off I give it a quick pump of grease too! Been on there for 3-4 years and is used pretty regularly

have you any photos

[Orgasmic Farmer]

Just checked and unfortunately no decent photos. Will try and get some tomorrow

[simonr]

Or fill the interior with lithium or moly grease then it runs pretty much for ever with heavy use!

Some years ago I built a 90 with adaptive air suspension. It used inclinometers and pressure transducers to level the vehicle while cornering and on side slopes while maximising the articulation when required. In it's most active mode it used about 10cfm continuously. Even in its most economical mode, the compressor with a 50l reservoir ran 50% of the time.

With a compressor filled with grease, a typical compressor lasted 2 years. Assuming you only use it for general inflation purposes, I think it should last almost indefinitely.

You did get a tiny amount of grease in the air out - but the amount was trivial, perhaps 5cc per year and there was about 1000cc in the pump.

Si

[Paul]

My set up is one of the originals we put in the Tech Archive http://forums.lr4x4.com/index.php?showtopic=2115 which I did way back in 2005. It's been used constantly since then for tyres, airbeds and a rattle gun too. On many occasions my system gets used to pump up other vehicles tyres at the same time, that can be 20 or more 33" tyres from 12 to 35 psi one after another, and never a problem. I even used it when we were building a new home to run an air drill, but it struggled to keep the air up for the drill, whereas for the rattle guns it's copes fine.

I've always used the oiler and filter system and I've had zero problems with it for 6 years now. Having said that, I understand that pumping the compressor full of grease works well too and even if it didn't work quite as well a the setup with an oiler, the compressors are cheap as chips out of an old wreck, so even if it only lasted 5 years it wouldn't be a big problem.

[Les Brock]

Pic of Mine,

Before I sold the truck

I had a oil feed as well, no problems whatsoever.....

HTH

Regards

Les

[ejparrott]

Pic of Mine,

Before I sold the truck

I had a oil feed as well, no problems whatsoever.....

HTH

Regards

Les

When you say oil feed, I'm guessing one of the little auto oilers not a feed of the engine?

Your extra alternator mount just gave me an inspiration for my 109 camper - cheers Les!!

[mickeyw]

To widen this discussion, there's more than one type of LR aircon compressor. Most people seem to be using the Sanden type (pictured above) and fill them with grease.

I have the later Denso pump as fitted to serpentine V8s and I believe 300 Tdis. I use it for running my truck horns as well as tyre inflation via a reservoir, so hardly heavy duty use. I did stick a little oil in when I first commissioned it 2 or 3 years ago, but nothing since. I rarely use it at speeds above tickover, unless it happens to kick in while I'm driving. It been fine so far.

[Diff]

This one is mine (in the tech archive somewhere) - just grease and still running fine nearly 5 years later, though it doesn't get used every day.

http://forums.lr4x4.com/index.php?showtopic=13723&st=0

Regards, Diff.

[ThreeSheds]

Not finished my air installation yet, but just thought I'd mention that if you have Megajolt and you still have the 14CUX and air bypass valve active, then you can fool it into idling at 1500 rpm while the compressor is running by halving the number of flyback pulses into the ECU.

All it takes is a relay triggered by the compressor clutch circuit, which switches from the normal 'four diodes and a zener' to a 'two diodes and a zener' circuit.

It works pretty well - when I switch on the compressor the load momentarily drops the tickover, but then the ABV kicks in and the revs rise and all is fine.

Switching off the compressor sees normal tickover gently restored as the ABV closes in a series of steps.

Now for perfection I just need to delay the compressor clutch for a second or so until after the revs have risen

Roger

[mickeyw]

That could produce some interesting results if the vehicle wasn't stationary when the compressor cut in.

For my purpose I have my system live with ignition, so when the air pressure drops below a certain point the pump kicks in. This combined with an automatied idle increase is potentially dangerous. I'm looking at situations here where the engine would be below 1500 rpm but you are still moving, such as when slowing down and your foot's off the go pedal.

I guess Roger's circuit could also include the start inhibit switch if you have auto transmission. Then you could have the idle increase isolated when in gear. Options for manual transmission anyone?

[ThreeSheds]

Good point Michael - I should have thought of that!

In my case the only safety is the master switch with a big red cover that needs to be lifted before switching on and some Dymo that says "WARNING ONLY USE COMPRESSOR WHILE VEHICLE IS STATIONARY" (actually that fell off but since I am the only one that ever goes in the car I think I am safe

I did actually test it while driving along, but since mine is a manual trans it was no problem, and I don't think it would be even if it cut in unexpectedly...

Roger

[CwazyWabbit]

That could produce some interesting results if the vehicle wasn't stationary when the compressor cut in.

For my purpose I have my system live with ignition, so when the air pressure drops below a certain point the pump kicks in. This combined with an automatied idle increase is potentially dangerous. I'm looking at situations here where the engine would be below 1500 rpm but you are still moving, such as when slowing down and your foot's off the go pedal.

I guess Roger's circuit could also include the start inhibit switch if you have auto transmission. Then you could have the idle increase isolated when in gear. Options for manual transmission anyone?

Fit a TD5 speedo and then knock up a little circuit that takes the output from pin 1 of C1060 on the back of the speedo (doubles the signal output for ECU)

So basically if you are moving then there will be a waveform on this pin and it shouldn't be too difficult to use that to supress the increase in rpm..... maybe... just an idea

[Michele]

Voilà...this is mine.

Always wanted an engine driven one, there's a nice slot on the engine, saves room in the cab (or in the back), no noise (well I have the ARB behind the cubbybox already).

I swapped the bolt with a grease nipple, but if i remember well it's pretty much closed inside, so grease doesn't really go out and lasts for a long time.

I have a filter right after the Sanden and it never collected a drop.

The only issue is, with a bit of throttle it gets very warm and blows very warm air, and blew the filter bowl!

It should be placed well away from the Sanden, something I plan to do when I'll do the definitive setup (if there's anything definitive).

Recommended.

[landy_andy]

There was an artical in one of the US off-road mags a while back about using a Sandon in this application. There is an oil return hole in the bottom of the rear body plate that needs a plug putting into it. If you do this there is no oil carryover into the compressor side. Hope that's useful for someone ;-)

[the mutt]

We run a converted York compressor, runs at approx 120psi feeding a 10 gallon air tank, there is a high volume electric compressor ib the system as well for backup .

Glenn

[Defender]

I have a denso pump on my 300TDI I use air con compressor oil drip fed when the tank fills the first time, once the tank is full I open a valve to pull from open air without the oil. This has ben used on most outings as I run beadlocks on 35" tyres and I've had absolutely zero problems.....I used Diffs write up as a guide (Thanks Diff).

It works so well and as said if the pump dies after a few years they are really cheap to pick up second hand.

I've also done my tyres and all my mates on 5 trucks one after the other and it's not missed a beat although it does get warm!