360 A/C - R12 to R134a conversion

[pettaw]

Good news. You just have to make sure when you charge the system you don't liquid slug the compressor cos there's no space for the liquid to flash off as it enters the system.

[pettaw]

One more thing did occur to me. The conversion pieces may well go on there, but how will you get the R134a charging connection to go on both at the same time? They're pretty chunky.

pic from googling around cos I don't have time to take pics of mine:



If you're getting new hoses made up surely the A/C place could just place a couple of charge ports in the hose fittings.

[trabitom99]

Makes sense of course. Unfortunately the hoses are already being made up ... I'll see what they've come up with, I left the compressor with them so in theory they should see how little space there is. I drew attention to it anyway ...

Tom

[volvodspec]

they'll probably place 1 of them higher than the other to make sure there's enough clearence, we do that with the hose connections at terberg terminals too..

[trabitom99]

OK, I picked up the parts today:

new fittings for the compressor (they said they tested the gap with their machine, and there's enough space)


new (and old) drier and pressure switch


new (and old) hoses


The problem with retro-fitting V300 A/C systems is usually finding the right evaporator - I asked if there were "universal" evaporators you could use. Apparently there are, and they come in all shapes and sizes - just a question of matching up the right one!

Tom

[Chris_C]

The problem with retro-fitting V300 A/C systems is usually finding the right evaporator - I asked if there were "universal" evaporators you could use. Apparently there are, and they come in all shapes and sizes - just a question of matching up the right one!

Now that does make an interesting find... I must look into sorting this too! Well done on the progress mate, I'm following this closely.

[foggyjames]

That's a happy box of parts...!

cheers

James

[trabitom99]

Right, nearly there thanks to Andy's massive effort the Sunday before last. In fact, we actually were there, and it was all working and cooling nicely, but when we took the front bumper off we saw that my water radiator is totally knackered, having lost almost 3/4 of its cooling fins (aftermarket jobbie, about 8 years old), so Andy had to depressureise the system again and I took the condensor out again the next day.

Anyway, here're some pics. Andy, please correct me if I'm not quoting you properly anywhere ...

Parts (nicely ordered) in the boot, and off to Andy's:


Bumper off:


Oh no!


Heater box out - old and new:

Hole in the bulkhead for the air recirculation, the old heater box didn't have it, the sound insulation just pops out:


Since the A/C equipment started out as an R12 system, the evaporator and condensor needed to be flushed out carefully using this special stuff:

Another important thing to remember is that systems which were originally gassed with R12 need to use Ester oil, rather than the usual PAG oil. PAG reacts with traces of chlorine, producing sludge which can clog up the compressor ...

Hoses old and new:


Dashboard out - easier said than done:


At this point, I was thinking "hm, I have a 400 mile return journey in this car in two days".



The air con switch is wired up to 12V, earth, the switch on the top of the heater box, and the "Speed 1" selector of the fan switch so the fan goes on when you push the button. The switch has it's own built-in bulb and is always on, a bit like the backlighting for the headlight switch.


The bulb holder dangling next to the clock holds the (blown) bulb for the heater controls - replaced that ...


The earth for the original relay was drilled into the inner wing, Andy spliced into the earth of the wiper motor so we wouldn't have to drill into healthy metal


Underbonnet view of the fitted compressor. The pulley on later cars already has a third groove for air con / PAS, but if you're removing / fitting A/C to an older car, remember this part as well! The groove is fairly rusty, so the pulley belt will be getting a fair bit of sandpapering ...


All in all - a rewarding day! The most important thing I learned was that you need to know what you're doing with the wiring (as Andy does, I would have been totally stumped on my own), you need a good, sturdy back to fit a compressor (or to remove one) and when you're removing A/C from a donor car, remember to keep absolutely EVERYTHING, including any screw, grommet or minature piece of wiring, if it's missing when you're putting it all back together, it all holds you up ...

Andy, once again, thanks loads for all your help and advice!

Tom

[trabitom99]

OK, it's all up and running now


Amazing how the compressor saps power, watching the dramatic decrease in revs from 1000 to 500rpm No idle speed compensation!

Just in time for, erm ... winter. I'll turn it on the whole time anyway, and wear a thicker jacket

Engine's running a tad warm (despite new radiator) but I haven't driven far, and maybe that's a subject for a different thread ...

Tom

[foggyjames]

Ok, who fed this man pimp juice?

cheers

James

[trabitom99]

[pettaw]

Not a very good video here. No details of the final touches mainly because we were getting pretty tired and I knew that I would have to drain the system down again as soon as I had confirmed we got it working.

http://www.youtube.com/watch?v=nG6l1o5Ml6A

[trabitom99]

Nice one, Andy! I like the quote "it's taken us a long time, but we've finally managed to install two buttons" Very flattering to me too, despite what the video looks like, Andy did most of the work.

No details of the final touches mainly because we were getting pretty tired ...

I was fairly weary by the time I got home ... After all that work it was a real pity having to take the condensor out again the next day, the car was getting really hot on the way home. But never mind, it's all refitted and refilled now (with the right Ester oil) along with a new radiator, a new Volvo water pump, and a new cambelt & tensioner.

Had the first real test of the A/C today (and probably the last this year). 26°C and a 45 minute drive along the Rhine. It works great!

There are some things I'm sure work better on the factory-fit systems though:

#1 the idle speed compensation (see previous posts)
#2 the full throttle cut off - power is noticeably reduced when it's on, I found myself turning it off a few times as I needed the power!
#3 the small extra cooling fan in the radiator shroud - in town the engine does get a bit warm (despite a new radiator and a new water pump). I may look into finding some solution for this next summer, the A/C place I went to nearby are sure to have something suitable in their catalogues. You can see there's an imprint on the inside of the plastic shroud, with screw holes, where A/C cars have the fan fitted.

Once again Andy, many many thanks - and to your folks too ...

Tom

[foggyjames]

Tom,

I have one of those fans, and I don't think I'm going to use it. Having said that, I'm not sure that alone will be enough to cure your problems...

cheers

James

[trabitom99]

I have one of those fans, and I don't think I'm going to use it. Having said that, I'm not sure that alone will be enough to cure your problems...

That's a kind offer James thanks ... On the motorway it's fine, but in town, the needles just slightly at the edge of the warning light. I guess it's due to the condensor restricting the flow of cool air towards the engine, it's nothing to get too worked up ATM, but an extra fan might be useful when the outside temperatures get above 30°C ... Also, I had been thinking of doing some towing with the car sometime ...

I noticed in the parts catalogue - there are two versions of that fan, a "normal A/C" one, and a thinner one for PAS versions.

Tom