AC Conversion

[jerryyoung]

I'm the new guy on the forum, have a couple of questions regarding my 1971 108.018 280SE with 130.980 6 cylinder engine. Has anyone converted the York AC compressor to a Sankyo(spelling?) or other rotary compressor? I have a "Texas Bracket" that is supposed to allow you to do just that, however, no instructions or mount kit came with the bracket (won it on Ebay). Also, this system has been converted to R134, anyone had problems with this change over?

I am currently putting the old girl back on the road, put it in my shop to replace the water pump and "ship-wright" desease set in. So far I have:
a) Replaced the dreaded blower motor
b) replaced the heat control levers
c) reworked the heat valve (stuck, reason the levers broke)
d) replaced all shocks
e) replaced all rear suspension rubber parts
f) bunch of other minor stuff I won't bore you with

Next up is interior and repaint. Sorry to be so long winded, just stating condition of car.
Thanks

[dieseldiehard]

I know a few Texas Braggers, never ran into the Brackett family yet. (I couldn't resist - I was born there too, shame!)
If you get any info on the company that made it let us know.
First I would see if there is a spot on the engine that a factory bracket is or was mounted and that is most likely the easiest place to find room for the new Compressor. You will need to get the right pulley for a compressor and obviously if it comes with one for a serpentine belt then you have another problem!
Whether the thing will fit your application or not you will be the person to determine.
I have wondered how to install such a compressor, so hopefully more knowledgeable persons contribute to this and I'll learn something and enable me to try replacing a York compressor someday.
Dieseldiehard.
'71 220 (gas) present project
'79 300D w/ '85 turbo engine @ 275K
'83 300TD 267K
'85 300D 290 K

[psfred]

All you need is a bracket to hold the new compressor in the same plane as the York.

However, unless the York is shot, they work VERY well, will freeze you out. They are noisy and shake some, but usually bulletproof. They work fine with 134a, too.

Peter

[dieseldiehard]

Thanks for the advise, psfred.
I have an untested but what appears to be a rebuilt (and slightly used?) York in my model 220, a 1971 W115 car. I was always under the impression that York compressors (or the overall system?) were more prone to leaking than the Delco compressors which are supposed to be longer lasting than piston style compressors. But what do I know? I am a newbie with the W115 model 220 I recently bought. Mostly because it had a manual 4-speed but the fact it had factory A/C was a plus. It has no power steering. It does not have the pesky Master Locking System either - (WHEW!) and No power brakes. Strange?

I am happy to hear that the York works well, so my effort in getting the AC running will not be wasted (hopefully!) OTOH I find the dryer to be miniscule in size, I hope I can find one to fit.
Dieseldiehard

[psfred]

Dieselhard:

The leak points are the suction and pressure line fittings (plastic seal underneath) and the carbon shaft seal, easily replaced. Seal repairs are easy (you can actually leave the system charged if it has the "real" Schraeder valves), and they tend to last longer than the rotary types -- those also have pistons, but it's usually 5 on a swash plate drive rather than 2 on a crankshaft.

Dump the oil, fill it up with good ester oil (there is a drain plug and a filler plug on the compressor) and evacuate, then charge with 134a and see how it works.

Make SURE the aux fan comes on -- you may want to pull the wires on the R/D and short them so it runs any time the AC is on -- else you will surely blow the high pressure hose. No longer available, but can be custom made.

The AC compressor will stagger that 220D for sure, but it will keep you nice and cool, if moving slowly. Be prepared to switch it off to accelerate!

Peter

[ctaylor738]

FWIW, the York on my 280C was converted to 134 and works great. They are fairly inexpensive and might be a better bet than messing around with the fittings to change to a rotary type.

[jerryyoung]

Thanks for all the info - I don't know for sure the York is shot, just saw the bracket on Ebay and thought it may be nice to have if the rotary units are better. I held the bracket up to the engine (fits on the RH side same as the York) but as far as I can see some spacets will be required. If I find any info on the bracket, I will post back.

Thanks

[dieseldiehard]

Thanks for starting this thread, Jerry -, I learned something. I remember looking at the factory manual showing the exploded view of a York compressor, with its zillion parts and gaskets.

psred, I already checked the aux fan, and it didn't come on when I grounded the thermostat and I didn't hear a relay click either (assuming there is one) - fortunately I have a spare aux fan from a later W115.
I will heed the advise on keeping the fan running. I like manually operated switches and stuff, that will be easy.
I know what you mean about switching off the compressor when passsing or going up hill. I used to ride with my finger on the A/C switch in a '79 non-turbo 300TD and I don't miss those summer days!

My 220 is very strong, it has a 230.4 engine installed which has been rebuilt. The puppy doesn't hesitate to run up to 70+ MPH pretty quickly (but not much headroom left above that figure!) thanks to the 3.46 differential I put in it (removed from the aforementioned 300TD).
Oh yes, why do you recommend R134a? if R12 is available isn't that better? I still have some on hand. I am not impressed by the R134a in my 300TD's. The old R12 really was COLD!
Dieseldiehard
'71 220 project car
'79 300TD w/ '85 turbo engine
'83 300D
'85 300TD

[psfred]

There is a set of fuses and a relay on the drivers side fender in front of the fuse box. Check the fuses and wires -- fuse should be always hot to the relay, and relay must close when the two wires on the receiver/dryer are shorted together or when you ground the thermostat wire.

If the relay doesn't close, check wiring -- if found that the connection to the fuse block was corroded, worked fine after that, but I blew the high pressure hose first.

Peter

[jerryyoung]

Peter,
Is the aux fan supposed to come on when the compressor kicks in or only if the head pressure reaches a pre-determined value? It would be fairly easy to set up a circuit to run the aux fan anytime the AC was on if it would be benifical.

New question - after a hard rain my LH rear floorboard is full of water - rear windshield seal?
Thanks

[Mark DiSilvestro]

Jerryyoung,
The aux.fan in my W114 '72 250 works off a temperature switch, which is screwed onto the AC filter/drier bottle at the firewall. The fan comes on if the filter/drier gets hot enough. Even when the AC was off, mine would come on if the underhood temperature was hot enough. I don't know if this applies to the W108 cars.

Happy Motoring, Mark

[Tomguy]

Originally posted by dieseldiehard
Oh yes, why do you recommend R134a? if R12 is available isn't that better? I still have some on hand. I am not impressed by the R134a in my 300TD's. The old R12 really was COLD!

That's the key - if it's available. I can't find anyone in my area that would fill it with R12!

Which brings up my question - what do I need to do to convert to R134a, just empty out all R12 left and refill with R134a?

[Mark DiSilvestro]

Do a search for '10W40.com'.

When you find the site, scroll down the text and click on the word 'search'.

Once on 'search', type in 'AC Retrofit' to find an article titled -
'Air Conditioning R134a Retro-Fit Manual' by P Parish.

Happy Motoring, Mark