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The great 240 AC system information dump + How to improve AC performance

QisofrKuin said:
This thread could not have come at a better time.
I recently bought an '81 244 DL, and I was told that the ac system had been converted to R134a at some point, and it looks to my untrained eye that they replaced the drier and the compressor, though admittedly I'm not certain. However, the line that leads from the drier through the firewall to the evaporator is damaged, so all the refrigerant is long gone and I can't test anything yet. Perhaps some of you who have updated your systems and had to redo the tubing can tell me, did you have to take apart the dash to replace the drier-->evaporator tube? Or can that be replaced without such drastic action?
Click to expand...

Did you figure this out? On my 87 I can see the side of the evaporator where the hoses connect pretty easily by removing the glovebox. I didn't take a photo but it takes < 5 minutes to get it off.
 
To pull an old thread up,
We made a trip down to Ft Bragg for some training and it is HOT here. And the AC isn't what it used to be. Although, the last time we re-charged it we were in the back of an oreileys in AZ after racing a jeep to get to the next camp site on the north rim of the grand canyon... (we won; except we rattled the AC fittings loose...)

That said, we now have a little one and it would be nice not to cook all of us on the 89 245.

Before this thread I was happy to just keep plugging the old style along and be content with having mediocre cooling. Now I am motivated to see about making the AC amazing.

Parts I am seeing that I need:
Compressor

Evaporator


New Style barrier hoses

The tool to crimp the hoses.

Still need a condenser, expansion valve, pusher fan and ideally the '93 firewall.
If I were to order from Coldhose.com do we know the size condenser?
On the expansion valve, just get stock from FCP?
I have a genuine fan but in a couple threads the word is that modern china junk pushes more air than the Volvo fan, correct?
Despite having a sticky parts thread, most of the websites are down or changed to something else. Does anyone have a source for the firewall parts to make the '93 evap fit?

Anything else I am forgetting?

Hope you all have an amazing Wednesday!

Andrew
 
What refrigerant are you planning to use?

You'll want the parallel flow condenser and a pusher fan. Spal fans are a good product. I tie the fan into the compressor cycle so when the compressor runs the fan runs. It also has an override switch to run the fan all the time.
 
Same boat as ams?

?88 245. Looking to replace all engine bay parts with r134a compatible ( hoses, dryer, compressor, condenser, new TXV). I want to leave the evaporator in place and just flush it correctly.

Can someone confirm I?ve got this right, that the original evaporator can be used but performance will suffer. I?m in northeast and don?t need the same level of service as my southern brethren.

Thx.
B.
 
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It appears that ad for the Nissens one is out of stock. There are a couple sellers across the ocean that are ~$260. I wonder if the ones Dave posted are Nissens brand, as well.

Pretty spendy, but what isn't nowadays. Thanks for helping me track down the part number, guys! :)
 
OldCarNewTricks said:
It appears that ad for the Nissens one is out of stock. There are a couple sellers across the ocean that are ~$260. I wonder if the ones Dave posted are Nissens brand, as well.

Pretty spendy, but what isn't nowadays. Thanks for helping me track down the part number, guys! :)
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Use the nissens part number to search on Ebay. There are a number of sellers.
 
dbarton said:
And so the cycle of trial and error begins. I have a feeling that using a "turns in" or "turns out" method of measurement will ultimately be meaningless. There are a number of manufacturers of TXVs and they probably set them at the factory based on flow or output pressure. One manufacturer's TXV at 5 turns may be very different than another's.
Dave
Click to expand...
Years ago, when Volvo offered the 'R134A conversion kit' if you did it right in the 240 it came with what looked like the later type EVAP with a TXV of some sort & a new 220CC R134A appropriate displacement compressor instead of the 160cc or smaller displacement compressors on the 4-banger 85-92 R12 240s & some ester oil that was compatible with whatever residual R12 mineral oil was on the hoses even after a good flushing...

The duracool needs the orifice size, compressor displacement & expansion space similar to R134A, but the high side pressures & high side fan switching even lower than freon R12 that its about as efficient as to work optimally.
I'd use the R12 1992 primary fan brown switch off the 1992 7/9 e-fan cars in 91-93 240s high-side switch location to switch the pusher fan on at a lower pressure.
A variable orifice valve for R134A (if the system is known totally clean, otherwise just fixed orifice tube/less to go wrong).
And an adjustable (off pre 1991 7/9s or 1991 240s) low pressure clutch cycle switch when using duracool to get the most out of it on a 1993 system swapped 240 since it runs low side pressures pretty crazy low to get the phase change/charge weight right with the water-free propane/isobutane that that stuff is.
Tropical fan clutch, 3-row radiator, Bosch 100A E-fan 940T 100A alt (or denso if that's what fits and it doesn't get too hot where you live over the black top) & some air guides all in place to shove the air thru the sammich help as does a healthy pusher fan recombining the junkpile.

Tough break as you say. That later R134A sized evap is LONG since NLA for the TXV 240 R134A dealer retrofit kit.
&, I'd rather have TXV & the dial/t-static switch to turn it down/run it less/save energy if I don't need as much BTU exchange, as it's more efficient, and, on a turbo model (or larger engine swapped/more crowded engine bay 240), I wouldn't want the CCOT GM/Harrison 1991-1993 system accumulator in the engine bay if I could help it.

Some enterprising individual needs to figure out how to recombine the junkpile to use the 93-95 220CC R134A compressor, route the lines not thru the front sheetmetal more like the 1991-1993 models with better hoses less prone to chafing or leaks & nice form-fitting hard lines/easy to remove compressor & use the later style EVAP as Volvo more or less supplied (I wonder what GM car that comes in with fittings that Volvo found a TXV for in the dealer R134A retrofit kit??).

Make the engine bay less busy, compressor/hooptie accessory bushings less fussy & give more engine bay space than just swapping a complete 1993 system in (BTDT a bunch of times), especially if you don't want the accumulator in the engine bay and want variable T-static control which did work well when it worked/didn't leak with the R12 installed, but obviously that stuff is $$$ & not really legal/ethical to use, sooo

If someone else has to service it, totally understandable to set it up with all R134A stuff, but for shade tree hack owner-operator shens, not worried about ~6.0oz of 'dry' no water content propane/isobutane ZOMG burning me to death and don't want to pay dupont their blood money for their poisonous inefficient R134A they hold the patent on...

Harlard said:
Might be only me, but my ?93 AC setup does not have a high side port.
Click to expand...
Remove the pusher fan switch to tap into the high side for a gauge reading after vacuuming & charging by exact weight with synthetic oil + quality gas on the 1991-1993 system...n00b...

Jump the push fan to just run while charging to make the refrigerant contract/get it ingested easier with the fan on low & engine fast idling at 1500rpm or so with the tropical fan clutch roaring away with healthy belts & low switch jumped, but don't let the evap ice or compressor get slugged...(there's usually enough safety factor that the refrigerant should boil in the accumulator, but the evap might turn to a block of ice pretty fast with the fan speed only on 1 depending on outside ambient temp/humidity). In AZ humidity isn't always an issue...
 
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Kjets On a Plane said:
Remove the pusher fan switch to tap into the high side for a gauge reading after vacuuming & charging by exact weight with synthetic oil + quality gas on the 1991-1993 system...n00b...

Jump the push fan to just run while charging to make the refrigerant contract/get it ingested easier with the fan on low & engine fast idling at 1500rpm or so with the tropical fan clutch roaring away with healthy belts & low switch jumped, but don't let the evap ice or compressor get slugged...(there's usually enough safety factor that the refrigerant should boil in the accumulator, but the evap might turn to a block of ice pretty fast with the fan speed only on 1 depending on outside ambient temp/humidity). In AZ humidity isn't always an issue...
Click to expand...

I had a chance to use a 93 940 compressor and didn't take it. Maybe I'll swap one over if/when it's apart again.

Currently using the ECU to trigger a fairly well-sealed 940 fan at low speed whenever AC is requested. High speed mode is triggered by the pusher fan switch. No mech fan nonsense for me, at least for now.
 
Last I drove John lanes rally car the mech fan with the old made in Japan Aisin tropical thermostat clutch goodie on the front of it worked just-a-fine? V6 models have a larger fan blade, clutch & shroud opening on the last of the 700 PRV cars that barely clears the hood with a huge 3 row all metal radiator on early V6 cars sold in AZ.

Powerful push fan off the V12 W140 Benzo works good in the Volvo?

Denso 100A seems to have enough grunt push it at idle.
Guys in AZ with the bright sun, 100+ degree temps & 130 + degree air over the scorching black tip report the denso loses charging voltage?the temp sensor reference is internal to the alt after all.

I suspect Volvo installed the Bosch 100A in 7/9 turbo electric primary fan models with lots of engine bay heat soak because they Have a ~13.5 minimum charging voltage cutoff (presumably they assume if using lead acid batteries and the temp sensor reference is indicating beyond ~212*F that the water in your battery?s vaporized/you have bigger problems? :lol:).
On a hot day with the air going full on a 940 turbo the engine really dips/almost stalls even when the cars were new even with the updated last year 1995 ECU to *try* to smooth out fan cut-in on the old redblock tractor running on antequated LH2.4 by then.

I suspect Volvo installed the larger radiator/intercooler & a/c condenser & electric primary fan for idling in traffic with the air going on heat soaked turbo models for sufficient cooling on wagon models for the USA sunbelt as a few well-to-Volvo customers were moving to the dirty south by 1992 (else, why bother?).
They had planned to keep selling redblock 7/9s here up -1998 but they wouldn?t pass OBD2+ emissions without a lot of work.

No real easy way to revise the front sheet metal on the existing 240 model they were about to kill off & no turbo model to heat soak idling as badly anyway, so clutch fan is fine?
Use 1-2 radiators & a/c condenser & piping / layouts for all 92-98 7/9s (turbo, n/a & whiteblock).

Still, I prefer the clutch fan, particularly on 200 series front sheetmetal & turbo models for heat soak reasons or towing under load as well as the dual belts when in good shape (the execution/ quality on those stooopid hooptie bushings & accessory mounts on all redblocks, notwithstanding :roll:). Like Larry David I don?t drive in traffic really ?I feel like I?m too smart / life?s too short to have gotten get stuck in traffic.?

850s & newer they wised up and there?s a little plastique duct to the airbox inlet/lid like many newer cars have to the alt temp sensor on the rectifier for battery temp reference?
Of course the crimp quality on the battery + cable on those that can fry a bunch of alts is another matter :roll:

27 degrees at the vents in low humidity on a 90+ degree day without setting it on recirc is about as cold as possible on the late 240 evap without risking an ice-up?
?amusing to shut the thing off after driving at speed/on the interstate in the CA valley at a gas station & find a lake under it and initially panic :rofl:
?O noes!???oh it?s just the condensate drain??derp/?dumbass??
27 might be too cold for 90+ degrees & 90+% humidity continuous circles around Biloxi, MS or something (or ~6hrs/300mi 60mph cruise between shutdowns/defacto defrost cycles for fuel fill ups a good 240?s capable of (or 400 mi fill ups if it?s diesel & you drive 55-60mph in the flat unloaded in a car running tip top on vanagon 185R14C pizza cutter tires at 50+ psi w/moon disc/89+ gas saver wheel covers & piss into a jug?:lol: )

I saw my fist ?hot weather? 1993 240 application only small pulley compressor clutch for idling a/c performance on the donor car in the Phoenix junkyard I raided for the 1993 a/c system for s friend I took pity on that moved to Tucson (well and my own self interest/free wing on the house now that I?m at ripe old snow-bird age & hate the winter gloom here, but can?t afford 2 houses :lol:) with the ?87 245 owned by the OSU college professor & took to Jack scoville Volvo (still locally family owned/old experience guys that know their stuff there?people keep their old cars longer down valley/less theft/city problems or fevered egos & yuppies down fhere) from new.

PNP buyer wasn?t at the auction that week so I put in a bid for $60 online and won the stupid thing by mistake, but the paint was burned off / wasn?t going to cosmetically clean up to showroom condition, so I wasn?t going to get top dollar for the car.

Everything worked on that car that never does off a generic 240 off the street unless you have an experienced dealer tech & paying customer repairing the cars back to new standards;
seat heaters worked (replaced driver seat bottom cushion & cover back and you could still get that stuff from the dealer ), a/c was low on R12 but worked, all 245 hatch hinge harness accessories worked, odometer /trip odometer and electric speedo worked, heater fan was dead quiet back when it came with an updated motor & new balanced impellers from the dealer & worked, heater valve fine adjustment instead of being on/off or always on worked (new OEM metal valve) , window scrapers worked, stereo with graphic equalizer & tape deck worked with OEM ?Volvo premium sound? rear speakers (LOL), accessory gauges worked (tach/clock & oil temp (stereo up top being an ?87).

Car had a broken steering shaft u-joint with the new Volvo tag on it; chinesium in the blue box. :roll: probably scared the OG owner after it was on the dealer receipt after owning it 30 years & he got rid of it even if he maybe didn?t want to/woulda kept it & kept taking it to the dealer if he coulda? Title was dated ?88?
 
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I?m running a 150a GM truck alternator in this here car. Between big stereo, big fan (advantage is I can set it to turn on at whatever coolant temp I want, unlike the 230? or whatever that the later cars were set at, which was a considerable contributing factor to excess wear). I also have headroom in case I want to run electric power steering and water pumps.

Currently my system is only spitting out vent temps ~30? below ambient, which is nowhere near good enough. If the charge is correct I?ll consider swapping in a spare SPAL 1000 CFM fan. Failing that, the tropical doohickey will take the place of the 940 efan.
 
I threw wires at my car last year so the ECU controls all 3 fans, the front two cheapie 10" pushers paired together and the two speed 960 fan. Front pushers turn on with AC, main fan low speed turns on at 180 something coolant temp, all 3 turn on full tilt at 190 ish. 100a rebuilt Denso doesn't exactly charge the battery at idle with all this, but it's not like I'm sitting idle with all the fans and lights going for long enough to kill the battery.

AC blows at a nut freezing 15-20f below ambient. At least it doesn't seem to have leaked any in the last year. Thinking I might try closing the TXV up to like 2 turns out, from the 5-6 it's set to currently.
 
With a 260 width 3-row & Lincoln Mark 8 giant fan you can probably cool it if it's got enough airflow & the rest of the A/C system is up to scratch...if you want an E-fan?

Or just throw the overboosted redblock time bomb in the trash can & get a proper small block ford (or Rover/Buick 215 if you're a masochist and want ultra-compact & ultra-light-weight all-aluminum-alloy and aren't afraid of Brit(ish)...ish as in ****...tho the 5.0L version in the TVR is fairly decent?...they're shy 1 head bolt from the factory & pinned liners/crank girdle to really make them perfect) that fits the 240 engine bay like it belongs there & forego the intercooler part of the equation in the heat exchanger sammich?

Or a B280 cross bolted main lower case + eagle premier 3.0 liners John Lane / 1000hp supercar cylinder head recombine that's period/volvo chassis correct & 'bolt-in?' :lol:
Enjoy super hard cylinder liners that don't squirm, crank/rod bearing journals ~1.5x the size of the redblock, perfectly balanced/smooth & quiet in the engine bay that far forward, Timing chain that never seems to wear out with gigantic baffled oil pump in the sump, all alloy/super light weight, no crankcase windage escaping the separator box/no need for a dry sump for track days, room for an electric assist/regenerative breaking giant 10 speed transmission in the stock trans tunnel, room for a giant turbo, much better machining tolerances etc? No easy or cheap way to rebuild it...

Whether or not there's sufficient belt traction to even pull the 150A alt at idle on the redblock tractor I dispute.
Max 240s ever came with is 80A (& those alts are nowhere near capable of that at idle when belt traction is likely to be worst with the alt producing at fully loaded draw & even the best of the OEM alts (Denso 100A) is only capable of ~70A at idle in sub 90F ambient.

I maintain that with the stock crank pulley even on a B230 (~6.5"? instead of B21/23 ~5.5"?) that there's only sufficient traction to drive the alt with the heater fan on full, ****ty little stereo these came with, pusher fan & engine cooling fan fully locked up at idle if it's over 100 degrees out even if the accessory bushings & OEM dual belts are all tip-top otherwise magically, somehow-or-other.
The water pump + alt pulley belt wrapped area adds up to the crank pulley belt wrapped area when added together. Why put it all on the ~50% efficient alt for the engine cooling?
70A draw at idle is about all the belt traction there is available, even in perfect shape, even 900rpm B21FT/LH1.0 thru 2.2 950RPM 'A/C on' fast idling speed instead of LH3.1 540rpm fuel sipper idling speed with the dished flywheel of LH2.4 700-720RPM idle regardless of A/C on or not...

You're not wrong that the OEM 230F heat soaking setup is ridiculous.
I just run a SAAB T in the lower hose with a 77-82?C CI FI SAAB/VW OEM made in W.Germany heavy quality brass Wahler Temp switch if doing the E-fan dance or same screw in switch in the upper radiator end tank as Volvo did for the pusher fan..
...not as sophisticated as a modern controller/probably runs the fan a little excessively, don't care for the mild steel of the SAAB T instead of stainless (but don't live somewhere with salt air or use corrosive coolant), but it works?

Rather replace alts & fan motor brushes a little more often than over-stressed A/C components/ground up A/C compressors that are over-worked...
The push fan is sort of a compromise I live with even though it might not be ideal for cruising economy at speed in the airflow there...
In cold weather you want the full belly pan, snub '83DL (1-year-one model USA only) air dam & blocked off grill for maximum hypermiling penny pinching & engine longevity. The snib 83DL air dam or no air-dam on the '73 skinny commandos is good for ground clearance on logging roads/going camping & urban warfare/bashing people out of the way parking. The snub nose '73 140 with optional bumper over-riders & push bar is a particular long forgotten factory accessory catalog favorite!

The super eco-dork Gen 1 Honda Insight guys run the VW 3-cylinder TDI, no A/C, 1800lb 3wheeled version, no side mirrors & a styrofoam aero plug for the airdam air intake in winter to scrooge squeeze 120mpg out of them reliably grid charging. :lol: No expedient 6-speed close ratio trans option for those. :-(
50-70psi o=in the ultra-low-rolling resistance Brigestone RE92 165-65-14 on the ~10lb slotted moon disc style magnesium wheels at 0 toe & camber alignment.. :lol:

Closing the TXV sounds backwards to me with R134 or duracool; R12 takes the smaller orifice size & requires less space to expand into.
As mentioned, the duracool really needs a larger compressor with comparable sized EVAP & condenser to expand into as R134, despite running at lower pressures/being more efficient than R134 (tho more prone to um finnecky sub optimal operation with large variation in ambient temps / loads for the heat exchanger...narrow efficiency range with that stuff without a variable volume expanding accumulator, smart expansion valve mounted right on a variable rate swash plate 3-phase smooth powered precisely controlled compressor like they use on modern variable refrigerant flow heat pumps). They definitely use hydrocarbon refrigerant in other countries where it's legal...well...and technically here too!.
Just as open-loop/combusting it as you light the outlet of your propane RV fridge/similar!
& presumably you still are sleeping near 100 gallons of the stuff in a big RV or operating a motorvehicle with that much of it on board/hooked up, but we don't talk about that...
~6-12 .oz of it in your auto A/C system is for sure 'ZOMG gonna kill you!!!'...yea that's it...

Someone/some OCD dork get out their HVAC engineer charts & physics & chemistry books & relative heat loss modeling/solar gain of a car cabin for all situations....:lol:
 
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To your point, I'm running accessories in the 740 configuration to avoid the heat soaking you mentioned. The whole engine bay could do with more ducting/better ventilation. As far as the redblock is concerned, I'll piss with the ?????? I got. It does everything I want it to do other than shake and resonate, and that's at least 50% a transmission "feature". I'm actually considering switching to an electric PS pump off a C30 or a Cherokee. If that's too much for the current alternator setup, I'll first add a second belt, then consider a serpentine conversion. Last ditch would be a modern PWM-controlled alternator with a one-way clutch. If that all fails, I do have a spare BMW engine to throw in. Ironically money is no longer object, but rather enough time to complete things reasonably quickly to attempt breaking the car.

As far as the cooling package is concerned, yes, the stock intercooler location is terrible and I'm presently considering another core in the front-low position. This would also ease packaging within the engine bay considerably. As it sits, it has a stock dual pass condenser, with a KL Racing intercooler, and DO88 radiator. If I were to do it again I would have ditched the 240T oil cooler long ago and gone with a 940 NA-style radiator core and an aftermarket cooler in a less inane location. Painted myself into a corner there and not ready to spend money, locate components, and make hoses with associated bracketry.
 
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