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

[Kjets On a Plane]

What's so bad about the stock IC location? It has lots of surface area & can be stacked up in a sammich with the clutch fan to pull air thru it continuous to prevent engine bay heat soak?
Easy to service, not in the way of damage in the front down low, no moving parts? The factory did ok with that no?

I'm not convinced the 7/9 alt location is any better other than the temp sensor reference if the alt has an internal voltage regulator?
All 700 models come standard with power steering & they sold RHD turbo 7/9s, so it makes sense on those grounds recombining the junk drawer as Volvo did on the cheap...
More belt wrap/stronger brackets on the last of the 7/9 turbo models, but I'm not convinced any additional belt traction is available overall to drive the cooling fan & alt than the 240 has, really?
It's a little less 'afterthought' than driving the PS pump off the A/C compressor like the 240 does, eh?
& a little less busy than the 4-groove PRV crank pulley as a hold-over from the V-belt era & GIANT displacement Delco-air A/C compressor those came with some years...

But obviously in '76 when the SOHC 240 came out they mostly sold the cars to cooler climates & wanted to be able to offer them sans PS or A/C at all, so despite needing more alt than a 140 with its single impeller heater fan/single headlights only (B21F 260s had quad headlights starting in '76) & only 6 fuses without A/C except as an add-on and R12 only (don't need as much airflow), no turbos, they gave the 240 SOHC dual belts instead of the single fan belt for both alt & cooling fan/water pump that worked 'fine' on the B18s & B20s...
122s came with a 6-blade fan with optional dealer A/C is the only difference I remember, 140s larger alt and I forget what else was in the dealer install TSB
I never bothered, but did consider A/C for the 145 w/D-jet, power steering & OD trans added later? 2x foot vents, 2 pop out rear windows, 2 vent windows, live in the baker wilderness/where you don't need A/C (yet, climate change/heat dome...who knows now?).

I liked the MR2 electric hydraulic power steering, but it was worth more to a Toyota guy removed surgically with the entire front harness labeled so I had to give it up as a complete MKII MR2 kit as it was a rare option on those (most are manual steer except max factory kool-aid loaded 3S-GTE turbo models usually).?

I'm surprised no one has adapted the Saturn VUE/Chevy Equinox & Saturn ION electric assist quality Japanese/Koyo made column (I think they even used it in the couple odd hybrid Chev suburbans they sold I forget?) in conjunction with a ZF manual sturdy rack (which we got very few of (usually only as dealer replacement in a -'80 car back in the day) with the 2.5 turn guts from sweden to get all the power steering stuff outta the engine bay entirely?

IDK what you do for the brake booster? Hydroboost? For your Coyote crate or ford V10 modular motor installs stuffed into an uncut 240 engine bay?
Electric hermetically sealed A/C (or heat pump/battery pack temp heat exchanger if EV?) compressor sans hooptie shaft seals or hoses to leak out of the largest cabin toyota hybrid/EV to adapt?
Electric assist 14kw motor in the bellhousing/no hooptie belt-drive alt?
*Just* the engine/tidy engine bay/no plumbing or wiring nightmare?

IDK if I wish I had/was living the 'more $ than time' option?
...that might require working on someone else's terms & conditions or for a company or entity I don't feel ethically right about or paying bills/taxes, no? Kinda wanna be done with that for this life?
Or..U know...actually trying at life &/or giving/taking orders or exploiting others / consuming resources? Be nice to experience it to have a reference, even if only fleeting...
& having $ instead of skill/time off/relationships in life isn't really a life? 'There was once a lady that was so poor that all she had was money.'
Definitely a long ways away from the 4 houses & private plane of dead relatives before they pissed it all away to go rags-riches-back to rags (plus bill collectors from expensive habits ) again...

 

[Harlard]

Do you really feel that way about Columbia Sportswear? Dang man, your standards are a bit high there, don't ya think?

RE: booster. IDK. Stock is fine until it fails for my garbage.

RE: EPAS: It's expensive and you wind up not having any steering feel. Kind of a non-starter
RE: MR2 pump - those things are mondo expensive and bring nothing to the table that a newer, more widely available unit can.
RE: 740 belt routing: It's less insane than the 240 belt routing and the alternator does not cook directly under a turbo manifold
RE:IC location - if the car is stationary, the thing heat soaks with the vengeance. Also blocks airflow to the radiator by a not-insignificant amount.

 

[Kjets On a Plane]

Do you really feel that way about Columbia Sportswear? Dang man, your standards are a bit high there, don't ya think?

RE: booster. IDK. Stock is fine until it fails for my garbage.

RE: EPAS: It's expensive and you wind up not having any steering feel. Kind of a non-starter
RE: MR2 pump - those things are mondo expensive and bring nothing to the table that a newer, more widely available unit can.
RE: 740 belt routing: It's less insane than the 240 belt routing and the alternator does not cook directly under a turbo manifold
RE:IC location - if the car is stationary, the thing heat soaks with the vengeance. Also blocks airflow to the radiator by a not-insignificant amount.

eh, don't feel particularly anything about any corporation or anyone else's choices that much or think Columbia is worse than any of the others & don't make all my clothes in house / wouldn't have a clue how to?
Not much for marketing or multi-national corporations, but whatever, it's inevitable/what's for dinner...
...I don't blame individual people hustling in the rat race/taking what they can get, why should I?

I do prefer the feel of hydraulic directional valve steering, but I wouldn't call EPAS 'numb' exactly?

IDK what's happened with MR2 complete kits prices in the last few years?
I think I sold it all as a known good set complete for $750 to drop in a 40K mile MR2-Turbo that somehow was missing that critical option?
But I've had 3 of them go thru my hands over the years or so? They must be rarer now?
They used to be in the CA junkyards a fair bit on loaded N/A MR2s every 3rd car or so?

I don't sit in traffic if I can help it and only reverse commute & try not to live somewhere where I really *need* A/C in traffic or work anywhere where showing up desheveled & sweaty looking like a criminal/tramp isn't socially acceptable, but I feel for people that do need it or have kids or a dog where it could be life threatening/cook their brains?

But if the fan works right/always spins while the engine is running, it shouldn't heat soak hardly at all, especially if the rad is appropriately sized, no? Instead of the mickey mouse wait until it heat soaks & turn on the sort of marginal electric fan as Volvo did it?

I prefer the dual alt belts...the 700 setup is almost *even more* of a compromise to me with the 1 hooptie belt for the water pump & alt each. But I do like the stronger (1995-only?) 940 alt/A/C bracket with the *slightly fewer* hooptie bushings & stronger stamped steel accessory arms when junkyard recombining for someone with a 7/9 4-banger looking for a drop in no fuss update/upgrade?
Along with the 1995 (only for the 4-banger) better 940 brake booster to make the brakes suck somewhat less on those things...

I don't think the alt being on the exhaust side is *inherently* a problem?
...they had heat shields on 240Turbos & the alt lasts ok if the motor isn't a leaky mess & belly pan is in place & fan clutch is tight/functions as it did when new & always blowing on it if temps climb?

The battery temp sensor reference being taken from there does kind of suck on models with internal voltage regulator...
...the early 240/140-Style external regulators when used heavily at idle are often flickery/under & over charge & reduce battery life.
Lots of OEMs put alts in hotter places than a 240Turbo & have them last 150-200K or so or better? The whole turbo engine bay is hot IDK?
I think more the issue is the alts on 240s live with leaky roached out engines, sitting sideways with shriveled up oil soaked accessory bushings & no belly pan going through puddles/road slop?

 

[Harlard]

A roached Mr2 pump goes for $400-500 when other fresher units (Chrysler/Volvo C30) can be had for less money.

As for the fan-on temp, I have it set to switch on at 190 or 200. I think it needs to go down as I do not usually like it getting hotter than 210 or so. I should probably change the switch-off temp so it does not get too cold in the winter.

The intercooler heat soaks when the AC is off. Even then the condenser is pumping interior heat directly into the engine bay, so it's still less than ideal. The theoretical coldest temperature achievable is ambient, and even then it does get warm enough to note a performance penalty on a warm (>90*) day.

As for alt heat, good to know on the bracket. I have a '94 one here. Keeping eyes open for cracked brackets right now. I just like it better. I do think the alternator does better, based solely on casually observing output on both locations and seeing a ~.5v difference on hot days. I forgot to mention I have a lot more access there with the PS pump in that location (small bonus - no bushings). If you are going to argue about boiling fluid, I did add a PS cooler on the return line.

As for "needing" A/C...this is simply an exercise in futility: can I do a 400 whp 240 that is comfortable enough to drive mostly year round and not look like a hot mess after 30 minutes?

 

[Kjets On a Plane]

I'd almost think an FMIC would heat soak even worse down low over the hot pavement without the engine cooling fan pulling air thru it continuous as the Volvo does with the A/C off?
Hotter IC with the A/C going, but whatever, price you pay for comfort & forced induction & the sammich of all 3?
No heat soak with a steeper pitch fan blade & B230FT 700T 'small' water pump pulley & tropical clutch
Blown out heater cores revving it over 6K (even with the brass impeller 'solid' water pump) w/the small pulley, yes, however.
Might be fine with an L or M-cam that's done by 4K in the tractor anyway?
...even the T-cam revs decent with a cleaned up head/max power is rated at 5300 even with the log manifold & garrett T3, much less a ported 90+ and better flowing turbo than the cosworth 60 trim T3 w/.63A/R exhaust housing dinosaur max power happens ~5800/water pressure really climbs over 4500rpm at the back of the engine, even with the larger water pump pulley & B21/23 smaller 5.5" crank pulley, even with the heater valve open/no obvious restriction anywhere...

.5V voltage drop makes sense to me? E-fan car, hot engine bay, temp sensor reference internal to the alt (IDK what idiot dreamed that up or spaced out putting a tube of fresh air to it or moving it to some place similar to the battery for heat (passenger front fender apron like it used to be on external regulator models?). Something got overlooked/lost in translation there I suspect when they just started sourcing internal voltage regulator alts with the temp sensor inside but didn't include an air duct like you see under the hood of 850s/BMWs and other 90s cars/one generation newer in design.
But I don't think the alt being down low/passenger side is a problem in its own right?

Last of the 940s have a little nicer stamped tensioner arms for the A/C compressor and bracket/no fuss.
I forget the VIN # break, but '95 model year, yes?
You're not wrong; I don't want the plumbing mess of the PS pump on the passenger side & don't care about loud stereos in the car or electronics/heavy electrical load for long periods of time while the car's idling?

Was having some problems with the PS pump turning into a bit of an ATF fountain at higher speed auto-x (reaching mid-top of 3rd gear speeds (80mph?, lots of steering) at the end of a hot day...didn't go as far as using a cooler, but did switch to the $$$ silly Amsoil ATF & that seemed to resolve it (ish?...might still be questionably borderline 'too warm,' but nothing seemed to be failing/puking fliud? ) next time (hard to make apples-apples comparison...different course, different day, never put a temp gauge on it?)?
Was using the non-A/C bracket (no bushings FTW on the '85+ 240 non-AC PS bracket, either!) & 91+ style 240 pump on the driver side.

The AE86 GTS models came with a pretty sizable power steering cooler on some models factory for such a small light car, go figure?
I didn't have problems without it (mine didn't come with it), so I do believe it's a concern for certain uses even in a lightweight car with plenty of engine bay airflow/clutch cooling fan also...

Apparently, I got robbed selling the whole MR2 kit known good. Or not...inflation & storage costs/lot rot liability, adjusted! I did OK I think still?
I'm surprised hydraulic power steering exists on any new(er) cars of any kind at all with ever more hybrid & EV models sharing a chassis with a conventional ICE model?
Why bother with a pump, & fluid anymore/potential leaks/warranty claims if/when idiots dead-head it holding it against the fully-opposed steering lock stop when electric racks & columns (& by extension circuit boards & controllers?) have gotten so inexpensive?

 

[JohnLane]

Has anyone put any effort into fitting a modern variable displacement A/C compressor?
They work great (until they don?t)....
Also.... Systems with more efficient condensers and evaporators.... Why not run it on R-12 that is rather famously most efficient at getting heat out so the system isn?t running its whole life on the ragged edge?

 

[dbarton]

Also.... Systems with more efficient condensers and evaporators.... Why not run it on R-12

From what I read online, it stopped being made in 1996 worldwide, so to buy it now you get to pay ultra high ebay prices for 25 year old cans. And with such high costs, I would also be concerned if some of those cans are NOT REALLY genuine R12. With so much counterfeiting going on, could there be counterfeit R12 cans being made and filled with something else? How would you ever know?

 

[Cwazywazy]

With so much counterfeiting going on, could there be counterfeit R12 cans being made and filled with something else? How would you ever know?

Taste test.

R12 is illegal for a reason. Even with how infinitesimally small of an impact 1 ac charge worth of r12 would have on the environment, I still wouldn't feel good about it. Plus it's pricey, like you said.

That said, it's probably still being produced somewhere in China.

 

[dalek]

Lots of OEMs put alts in hotter places than a 240Turbo & have them last 150-200K or so or better? The whole turbo engine bay is hot IDK?

VW has alternators with coolant lines on them

 

[dbarton]

Kjets On a Plane:
Lots of OEMs put alts in hotter places than a 240Turbo & have them last 150-200K or so or better? The whole turbo engine bay is hot IDK?

The issue with so much heat is not durability. It's the huge voltage drop with Bosch alts. Up to 2 volts between cold and hot with the worst drop at idle.
Dave B

 

[Kjets On a Plane]

VW has alternators with coolant lines on them

Germans do all kinds of gimmicky needlessly convoluted crap, especially VAG that might work great in theory or if everyone maintained their cars perfectly & replaced / EU-style recycled them every 10-15 years with absurdly rigorous stringent 6-month to yearly safety/emissions/running inspections & operated the cars exactly per the book on roads maintained to autobahn standards & garaged them?
?meanwhile in the real world with our Swedish tractors that can make it thru 30-40 years of neglect/abuse & be repaired when they break instead of preventatively (not that that?s a bad idea?) / ?good enough?
Liquid cooling isn?t a bad idea though? Not sure I?d want any of the rest of the eu mandate recycled plastic over complicated German cars?

The issue with so much heat is not durability. It's the huge voltage drop with Bosch alts. Up to 2 volts between cold and hot with the worst drop at idle.
Dave B

I don?t think that?s the brand of Alt?s fault so much as the temp sensor being internal to the thing and lazy slap dick hack turbobrickers not having all the exhaust heat shields in place &/or using an external regulator temp sensor (not I?m installing any aftermarket ?adjustable? voltage regulator crap on my car instead of OEM to fry anything?) &/or using the 850/960 Bosch 120-140A alt (same guts as 92+ 940 turbo except mounting locations & pulley for redblock if you redblock guys need OEM parts, also used on some bmw & VAG eurotrash) style rear alternator casing with the duct for air from the front of the car for the battery temp sensor reference?

Turbo engine bays are hot, but on a healthy 240t with a good flowing turbo & 90+ manifold no cat with all the heat shields & offset to the passenger side & down (unlike the straight e-fan & 700 style fan shroud) turbo/240 style fan shroud, the engine cooling fan is always blowing air over it with the belly pan/rest of the air guides in place.
Further, all of the ^ sorted, i didn?t note the 240 alt being all that much appreciably hotter than the 700 location?whole engine bay is hot battery included after some hot runs with the a/c going even if the pusher fan, mech fan works as it should & radiator & intercooler is reasonably efficient.
What?s the coolest the air blowing over the alt (or rest of the engine bay behind the fan shirt or right behind the headlights while on the highway like where the battery is located with some metal between it and the hot pavement so it isn?t as prone to cook as modern car?s batteries at the rear of the engine bay/evaporate the water in az) continuous could possibly be idling over scorching 120-130F blacktop? 160F? even if the push fan & tropical fan clutch are keeping up with engine cooling demand & a/c is blowing sub 40F and there?s air blowing over the alt/IC/passenger side of the turbo motor continuous?
How long would the battery even last if it were at the back of the engine bay like many newer cars even with more precise charging systems/controls with the water in the battery nearing the 160F of the air blowing over most of the engine bay except where the battery is in the 240?

Give the alt battery temp sensor air the same temp as the battery & it should work just fine?

Or just don?t live somewhere so hot / borderline uninhabitable but this place is already overpopulated & overcrowded & hot sometimes too?

 

[go240go]

Long post about A/C here, but hopefully helpful as another data point in A/C work on 240's.

Car info: 1987 245, was R12 now Envirosafe, rebuilt compressor, original condensor/evaporator, new TXV

I just charged up with Envirosafe Industrial and am getting around 40F at the vents, depending on where I dial in the A/C thermo-switch. This was just in the garage at idle, so I've yet to see what temps I get in the sun driving around and sitting in traffic. It briefly hit the low 30's when I turned the dial to max for a couple minutes, so that seemed promising.

Some years ago I put in a rebuilt compressor (Kiki Diesel) and dryer, vacuumed the system, thought it was fully sealed, and charged with R12. It held for a little while and it lost all but 15PSI. It stopped kicking on at that point because of low pressure and I stopped caring. Also corona came around and I stopped commuting so it mattered a lot less.

This time, I replaced all of the o-rings where the system had been fiddled with/opened when I had to replace the front core support, installed a new TXV (OE Volvo, confirmed the adjustment was the same as the original by looking at the number of threads visible above the adjustment hex head - about 4 threads. The new TXV was stamped with R134, so who knows what's right/wrong), cleaned out the evaporator box (it was partially full of leaves/gunk), new dryer, vacuumed again, and charged with 14oz of Envirosafe Industrial. I did the o-rings most of the way around because I noticed stains at the hose connections going to the condensor. That's likely where I lost the R12 before, and it confirmed that pulling vacuum to check for leaks is inconclusive. It would've been great to do a pressure test, but I don't have a tank of nitrogen in the stash.

I hope it stays charged this time - I'm keeping an eye on it for the next several days with the gauge manifold connected. So far at rest, the low and high sides equalize to about 105PSI at 80F ambient. While running, low side is 30-35PSI and high side is 200PSI, at 90F ambient. Does this seem right?

I still need to re-butyl wrap the hard lines under the dash around the TXV, inside the evaporator box, evaporator box lid, etc. and reseal and install the lid. I don't believe the thermoconductor wires need to be wrapped, or do they? Without butyl, the hard lines sweat a ton. Is there a drain line for the evaporator box that I need to check/clean before re-sealing everything?

The one big thing I wish I would've done is flushing the system. I didn't realize it was something readily rentable or buyable at the standard auto parts stores until I had already installed the new dryer and fresh o-rings and returned the vacuum pump. Other things to potentially figure out are an electrical fan for the condensor and what looks like a lazy clutch on the compressor. If idle temps aren't great, hopefully a fan for the condensor helps. For the clutch, it slips for 4-5 turns before it fully grabs and catches up with engine speed. Is this adjustable on the Kiki compressors, or is it simply on its way out?

BTW, this thread was super helpful and got me to re-do the A/C again - thanks OP!

 

[dbarton]

So far at rest, the low and high sides equalize to about 105PSI at 80F ambient. While running, low side is 30-35PSI and high side is 200PSI, at 90F ambient. Does this seem right?

Sounds high, but probably not high without a fan. Adding a good condenser fan should help bring that down.
Dave

 

[ams]

Ok, how did you all get this condenser in there?

Got the cold hose 16 x 26 condensor. Which would fit if it wasnt actually 16 x 27 1/2.
How did you all get this thing in?

Thanks!

Andrew

 

[dbarton]

Got the cold hose 16 x 26 condensor. Which would fit if it wasnt actually 16 x 27 1/2.
How did you all get this thing in?

Mine actually measures 26 wide. I'd call them. Maybe they sent you a 16 x 28.
Or maybe mine was a 16 x 24, which actually measures 26. Let us know what they say.
Dave B

 

[go240go]

I talked to someone at Enviro-Safe and he said the pressures seem about right, along with the temps at the vents. He confirmed 1oz of ES equates to 3oz of R12, so just under 2 cans for a '87 240 is right.

I didn't see a drain hose that I could see for the box on the side of the evaporator coil, so I went ahead and butyled everything up and resealed it (white stuff for the pipes and lid, black for the lip around the box lid). When I removed the lid for the box I was able to wiggle it out without removing the ducting to the windshield and the passenger side, but re-installing the lid was impossible without removing the ducting. I should've done that from the start - so much more room and visibility, along with the ability to work on things through the glovebox opening.

Pressures have held up for 3 days now, so all seems good. So far, ES Industrial is doing the trick.

 

[2 old for this]

Yes there is a drain hose on hvac box,it?s on the bottom and goes thru the top of the top of the trans tunnel. Access it from the passenger side. Knee pads are required.

 

[ams]

So panic set in as we were needing to drive from just north of DC to Quantico. We made it fit?

Is there an easy way upload photos from my iphone?

 

[go240go]

Thanks @2old for this! Haha thanks for the tip on the kneepads. My sides and back are still sore from redoing the butyl under there.

 

[Khrrck]

So panic set in as we were needing to drive from just north of DC to Quantico. We made it fit?

Is there an easy way upload photos from my iphone?

imgur.com is what I usually use. Or I think icloud has a Share button which will generate a link you can open in web browsers.