onboard air

[greggy]

gidday all,
I've just finnished my home made compreesor in the Mk and couldn't be happier with how it turned out. I bought a cheap supercheap 2Hp compressor and pulled the electric motor and pump off. This gave me the tank, pressure switch and BOV. I used an old a/c pump off a mazda I had laying around and married it up to the tank. I can now air up from 16psi in four minutes for four tyres with the engine on idle. job cost around $130.00

[aksniss]

Sounds great, do you have any pics??

[carlos03]

sounds like a useful thing to have, did you choose an air con compressor that had the oiling system separate or did u drain the oil and use grease?

cheers
Carl

[aksniss]

I have heard that the Volvo compressors have a separate oiling system

[GUDeano]

Old volvos use a york compressor which has an oil sump so you only need an oil separator on the air outlet, and plumb it back to the sump.

[Crooksey]

in reguards to setting up an endless air with a standard air con compressor, what is the easiest/most practical way to go about this? is it to sorce a separate oilling system to over overcome the lack of oil without the aircon gasses, or is there a way so set up a standard aircon compressor to self oil??

[Crooksey]

ok dont mind me found heaps of post about this already

[aksniss]

With all of these compressor set ups there is really only one issue.

Where the hell do you mount one on a 30TD?????

[OldMav]

Originally Posted by crooksey

in reguards to setting up an endless air with a standard air con compressor, what is the easiest/most practical way to go about this? is it to sorce a separate oilling system to over overcome the lack of oil without the aircon gasses, or is there a way so set up a standard aircon compressor to self oil??

Crooksey there is a way to make a sanden sd508 series A/C to be basically self lubricating without the grease or oil ending up in your tank, it is a simple mod by removing the backing plate and blocking off the 4mm hole in the suction cavity. This hole is there to pump oil around the air/con system. By taping a 4mm thread and fitting a 4mm grub screw in that hole stop oil or grease being pumped into your air tank, I have used the same system or compressor now on all my 4x4's since the seventies, the compressor was filled with a mixture of moly grease and some compressor oil, i add a bit when ever i think about it of when ever i see smoke coming from the compressor. I use to have a water trap in the line but don't bother anymore as it never traps anything including water as the air is to hot coming from the compressor to trap water, i just drain the tank regular. As far as i know only the sanden 5 and 7 series have the hole which can be blocked, i have pulled other compressors apart but they have different lubricating systems so they cannot be modded to stop this effect. The oil seperator system and drain back systems seems like a lot of hard work and expence compaired to a 4mm grub screw.
I haven't pulled apart a sanden sd508 endless air compressor to find out if they do this mod, but i am sure they would be smart enough to have done so. And BTW after using a onboard 8CFM air compressor you would never bother with a electric driven system.
On my Maverick i had the compressor fitted under the alternator and run off the alternator with a small belt, it wore out belts and flew off at high revs. now it is fitted under the injector pump on alloy brackets, my model doesn't have the vacuum pump there, a 1160mm belt fits around the steering pump and water pump and compressor it seems to pump more air at idle than before and i don't loose the belt at high revs so now it is always on and ready. Anymore info just ask.

[Crooksey]

Thanks heaps Peter, exactly what i needed to know.

Has anyone fitted a compressor with the vacume pump in place? It looks as though fitting it under the alternator is the only place it will fit.
Peter what was the reason you were snapping belts with it sitting under the alt, was it only doing it with the compressor activated of doing it off as well??

[OldMav]

Originally Posted by crooksey

Thanks heaps Peter, exactly what i needed to know.

Has anyone fitted a compressor with the vacume pump in place? It looks as though fitting it under the alternator is the only place it will fit.
Peter what was the reason you were snapping belts with it sitting under the alt, was it only doing it with the compressor activated of doing it off as well??

Crooksey
I spent a lot of time trying to get the belt to stay on, this i did achieved. But it is a real tight spot, guard needs to be rearranged a bit on a GQ, or a inch body lift makes it easier. the brackets need to be strong not like endless air brackets they are really a bit lacking, but they do work if you don't run the compressor all the time, and only turn it on at low revs. I eventually got the brackets strong enough to withstand the pressure required to have the belt tight to the point the brackets didn't bent. Because the belt is so short and the bend radius for a AA belt is over the limit for this short length the belt wears out or cracks due to heat build up very quickly under load it can actually smoke due to heat build up. Don't get me wrong it does work ok in that position but i seem to have a need to have my junk fittered to best practices, and never give any trouble so to speak. I have looked at TD42's with vacuum pumps fitted under the injector pump there is enough room there to fit the compressor, it will hang a little lower but should have enough wrap around the crank pulley, to not cause any problems, or a back turn pulley could be fitted without to many problems to increase crank pulley wrap angle. Mate you are dead unlucky i only threw the brackets out on the week end, rubbish pickup day here in caboolture was today, you could of had them free even, My rig is near complete again so all the old stuff is and has been thrown out. It just never entered my head that someone would be happy to have one of IMO failed cast aways.

[Crooksey]

Ah well, you cant win them all. I should have a look at going under the injector pump. if with no avail, i could always use my 12v compressor, how long do these take to get say a 5 gallon tank to 100psi, know of any forumlae involved. i think my compressor is a 70-90Lpm. Also how many tyres/how much of one tyre would it pump up from say either flat to 40psi or 20psi to 40psi?? any idea.

Cheers

[OldMav]

Originally Posted by crooksey

Ah well, you cant win them all. I should have a look at going under the injector pump. if with no avail, i could always use my 12v compressor, how long do these take to get say a 5 gallon tank to 100psi, know of any forumlae involved. i think my compressor is a 70-90Lpm. Also how many tyres/how much of one tyre would it pump up from say either flat to 40psi or 20psi to 40psi?? any idea.

Cheers

The Sanden SD508 A/C running just above idle will produce 230 lpm at 100 psi or 90 lpm at 300psi. With my 10 litre fire extinguisher tank there is more than enough air to use a rattle gun to remove wheel nuts on one wheel, by the time you get to the next wheel the compressor has kicked out. There is more than enough air to pop tyre beads back on with no tyre valve. I don't time how long it takes to pump up tyres but there is no noticable difference pumping up tyres from my truck or using my 100 CFM workshop compressor the hose and tyre gauge and tyre valve restricts the amount of air so that tells me the compressor will pump more air than the tyre gauge/valve will allow. It is happy pumping up tyres all day hence the name endless air.

[Crooksey]

so by that i would assume that the ac compressor would fill an air tank in a matter of seconds? on my 12v compressor it says 70-90lpm ( cant remember correctly) im sure that it said that was free flowing, how would that relate at 100psi giving that the duty cycle is at 100psi is only a few minutes on with about 10-15min off. Would it even be worth setting up an air tank by using the 12v compressor, or would this be to slow and annoying?

[OldMav]

Originally Posted by crooksey

so by that i would assume that the ac compressor would fill an air tank in a matter of seconds? on my 12v compressor it says 70-90lpm ( cant remember correctly) im sure that it said that was free flowing, how would that relate at 100psi giving that the duty cycle is at 100psi is only a few minutes on with about 10-15min off. Would it even be worth setting up an air tank by using the 12v compressor, or would this be to slow and annoying?

Crooksey
Are you asking me to baffle you with bull****, i will try and make it simple.
You 12v compressor will be 70 to 90 lpm no load maxium flow no pressure. It is probably a single cylinder, so you can half that flow at 100psi. 12 volt motors loose a lot of efficency when under load so it looses about a quarter of its revs once under load so the flow rate at 100psi is even less. Adding a tank to that is going to add even more constant load, so even less flow and more power and more heat on and on. In general terms with compressors, more cylinders better flow under load like a V8 more torque etc (general rule). The sanden has 5 pistons sd5** /sd7** the number is how many cylinders, so it is not effected so much with pressure load so will keep its flow rate at minium revs. These compressors are designed to give good flow at 300psi for pumping refridgent. Also i have another castoff 20 odd years old but hardly used. it is a magnium brand yankie 12 volt 2 piston compressor flow rate a true 140 lpm at 100psi, uses lots of power, It was fitted for a while on a toyota ute before i got the ****s and fitted the sanden unit, and BTW it is BIG requires the space of a large battery to fit but it will run a tank and rattle gun and refit tyre beads no problem, just a little slow compared to a sanden, also it needs a rest after 4 tyres.

[Crooksey]

Originally Posted by OldMav

Crooksey
Are you asking me to baffle you with bull****,

Hahaha try me

well that is what i expected slow hot and *****ty 12v compressor. looks as though ill have to chase a sanden compressor, have you got an idea at which vehicals have thesse compressors to give me an idea at where to start looking. Once/if i eventually get round to setting this up i may have to call apon your expertise in getting it done correctly, and maby even showing me how its done as your problery only around the corner from me

thanks heaps for your help Peter

Chris

[OldMav]

Originally Posted by crooksey

Hahaha try me

well that is what i expected slow hot and *****ty 12v compressor. looks as though ill have to chase a sanden compressor, have you got an idea at which vehicals have thesse compressors to give me an idea at where to start looking. Once/if i eventually get round to setting this up i may have to call apon your expertise in getting it done correctly, and maby even showing me how its done as your problery only around the corner from me

thanks heaps for your help Peter

Chris

Arr we now have a name Chris, Yes i am probably only around the corner, or my workshop is the large shed on the airport just look for large boats.
Sanden compressor were used on any retro fit air conditioner in Holden or ford from the seventies most non factory early dunnydoors have them some of these had SD7** the factory V8 308 dunnydoors had sd5** standard. The wreaker down the road had shelves full of them before he moved i haven't looked since he cleaned up his act.

[OldMav]

Originally Posted by OldMav

Crooksey there is a way to make a sanden sd508 series A/C to be basically self lubricating without the grease or oil ending up in your tank, it is a simple mod by removing the backing plate and blocking off the 4mm hole in the suction cavity. This hole is there to pump oil around the air/con system. By taping a 4mm thread and fitting a 4mm grub screw in that hole stop oil or grease being pumped into your air tank, I have used the same system or compressor now on all my 4x4's since the seventies, the compressor was filled with a mixture of moly grease and some compressor oil, i add a bit when ever i think about it of when ever i see smoke coming from the compressor. I use to have a water trap in the line but don't bother anymore as it never traps anything including water as the air is to hot coming from the compressor to trap water, i just drain the tank regular. As far as i know only the sanden 5 and 7 series have the hole which can be blocked, i have pulled other compressors apart but they have different lubricating systems so they connot be modded to stop this effect. The oil seperator system and drain back systems seems like a lot of hard work and expence compaired to a 4mm grub screw.
I haven't pulled apart a sanden sd508 endless air compressor to find out if they do this mod, but i am sure they would be smart enough to have done so. And BTW after using a onboard 8CFM air compressor you would never bother with a electric driven system.
On my Maverick i had the compressor fitted under the alternator and run off the alternator with a small belt, it wore out belts and flew off at high revs. now it is fitted under the injector pump on alloy brackets, my model doesn't have the vacuum pump there, a 1160mm belt fits around the steering pump and water pump and compressor it seems to pump more air at idle than before and i don't loose the belt at high revs so now it is always on and ready. Anymore info just ask.

Chris
There is another simple mod the Sanden compressor requires to flow air to its full capacity, i forgot to add. The suction and discharge fittings on the compressor need to be drilled out as the holes in the back cover are very small. the discharge hole in the end plate is about 3/16 inch drill it out to i think 7/16 inch or 1/2 inch, the suction inlet hole in the case is about 5/16 inch drill this out to 9/16 inch.

[greggy]

sorry fellas the modem died last week and i just got back on line, I haven't looked into the ins and outs of the compressor but i have got a small inline oiler for the vacuum side. As for pictures I have windows 98 and have a hard time getting photos up from our camera, new p.c. in about a month. The positioning for the sd33 is just to the passenger side of the rocker cover using the same pullies as the original a/c just add a longer belt. I also had to cut the bonnet webbing back a bit to get about 20mm clearance. It hasn't thrown a belt yet but have not given a big workout, my engine very rarely sees 4000 rpm lucky to see 3000 most times.

[greggy]

The new pump failed me this week, overheated,stopped pumping, we had four cars and a boat trailer to air up and the compressor pump was not up to it. I will have to look into modifying the pump as mentioned by old mav.