91yota3.4

I have a 91 ext cab Pickup.
I am Installing AC using the factory stuff.
Toyota converted to R134a sometime in 94, I want R134a because it's cheaper, and I don't even know If I can get freon anymore.

A guy sold me a complete system for a 94 runner, told me it would swap right in.

It doesn't.

The box is to big. Is this problem due to the r134a system, or the fact that it's from a 4runner?

The plug is not the same in my truck. I'm pretty sure this is due to the 4 runner, because I've read they have a fan that the trucks don't for the extra air space in the vehicle. This would account for different wiring.

Also, my plug is way up in there, and has no length or play in the wires. In other words I can't pull the plug down to plug it into the box, even if it did fit, which means it would be really hard to try and splice it all up.



So, do I find a truck cooling box? A R12 box? If I find an R12 box will the fittings through the firewall fit the rest of the R134a stuff?

I'm ready to starting shooting this stuff.

Thanks in advance to anyone that can help me.

Emt-Iyotaguy

I actually just did a swap just like this on mine. You Probably will need to get the Box from a truck due to the size diff. As for the wiring there is actually a pigtail that came on the trcks that just plugs in to the factory harness and extends down to the box and low pressure switch, any way if you didnt get that when you picked up the rest of the parts you may pull it from a junk yard thats what i had to do and i cost me like 5 dollars

91yota3.4

So you think the size difference is due to it being from a 4 runner, and not the fact that it's a r134a unit? That would be nice. What year/make is your vehicle, and what year/make was your AC stuff out of?

Thanks,

anotherjeff

"...told me it would swap right in..."

Oh! The stories I could tell...

I take it that you didn't actually see the donor vehicle. Are your new parts actually from a 134a vehicle? The fittings, and possibly labels, would be clues. Did you get all the parts?


The electric plugs don't match? That's a clue that something is very wrong! Without seeing, I'm guessing it's a '84-'88 box. Although there is a small wiring harness on the correct box that could be missing. Pics may be called for...

I believe the R-12 parts and the 134a parts have the same footprint. The under-dash boxes should be visually identical. The electrical plugs should be identical.

Since ALL OEM A/C during that era was, in fact, "dealer-installed", a given truck might be either R-12 or 134a, just depending on which "kit" was shipped. As an aside; does anybody know if this information was recorded by Toyota? (Is it reportable by VIN?)


The box should fit! Do you have any recourse with the parts seller? Or, do you plan to forge ahead and resolve any discrepancies, like scrounging another box and mix-n-matching?

abecedarian

I just did a quick part lookup at autozone and the evaporators under the dash are indeed different between the 94 4runner and 91 truck. Could be a combination of the larger cabin and the conversion to 134a that caused it or they may not be related. 134a is not as efficient as 12 so a larger evap is an option to get more air cooled.

as for the wiring, your truck probably has a three speed fan and the 4runner probably had the 4 speed, so the wiring harness may be different for that reason.

anotherjeff

Yea... Not convinced, though. The fan is independent from the a/c. This is from the '95 4Rnr FSM:

91yota3.4

Maybe I worded that wrong. I have the fan, it attaches to the condenser. I read that the pickups don't have this, just the 4runners.






I trust the person that sold it to me, and I'm sure it's r134a stuff as you can see from the pic.

Thanks for everyone's input so far, and thanks EMT for the pigtail info, that makes perfect sense.

I guess now all I really need to know is if this size difference I'm dealing with is a 4runner thing, or a R134a thing?

abecedarian

so you mean the external fan?
I've never seen a pickup with one.

Emt-Iyotaguy

No problem been there myself and that little schematic above shows kinda what it looks like if you need anything else just ask

ozziesironmanoffroad

i would have stuck with R12... r134 is just a way for them to make money. r12 is so much better. id sell what you have (since its not 'BOLT UP') and buy an r12 system out of your exact year, model, and engine. SEE the donor vehicle. if not, then id get ahold of the FSMs for the 2 vehicles and get ahold of a soldering gun. get studying. good luck! im looking forward to seeing this mod

anotherjeff

I was referring to the (3spd/4spd?) heater fan being wired independently from the a/c control unit. Although, it's really the A/C fan, as well.

Apparently, only the 4Rnrs come with the condenser fan. It would be a nice upgrade for the pickup.


abecedarian, are you saying 134a pickups do NOT have the condenser fan? (I don't know. Seems like they would.)

Your parts look right. The condenser is larger than the R12 version. The underdash box looks the same as R12/pickup versions, the evaporator core may be larger. I have a R12/pickup underdash box out in the shop. I'll dig it out and snap some pics for comparison.

anotherjeff

I have to disagree. The OP already has the BEST combination! A bolt-in OEM 134a system for '89-'95 trucks. These are rare!

While, "R12 systems work best with R12!", an OEM 134a system can be expected to function as well as an OEM R12 system. Plus, being 134a, there is no worry about availability of the coolant. (Well, that's not exactly true, but that's another story.)

anotherjeff

The FSM illustrations for the '93 Pickup and the '95 4Rnr don't show any difference between boxes:

abecedarian

but it's a 91 pickup and 94 4runner.
so comparing a 93 truck to a 93 4runner is not the same.
even autozone has different part numbers for a 91 truck and 94 4runner evap.

anotherjeff

Lo and Behold, the exploded diagrams for the underdash boxes DO show differences!



abecedarian, i'm assuming that the '93 Truck FSM is applicable to the '91 (not a stretch), and that the '95 4Rnr FSM is accurate for a '94 4Rnr. And, upon looking a little closer, yep, there are differences. There's still the possibility that the boxes have the same footprint, e.g. they interchange. But, the OP's experience suggests otherwise.

abecedarian

...I think I said something along those lines.

91yota3.4

Right, thanks for all the diagrams, I have those as well, and was already aware of what has been said.

I didn't not notice the blown apart cooling box pics and the differences there. Thanks a bunch for confirming that Jeff.

I can't stick with R12, because as far as I know it's banned in Canada, or at least extremely hard to find and expensive.

Now all I need is a diagram showing a R134a Cooling box from a pickup to see if my difference is due to the 4runner, or the R134a.

I can't find a 95 pickup FSM in any of the FSM links, does anyone have one? I'll keep looking.

anotherjeff

R-12 is graymarketed in the US. Lots of it on eBay, swapmeets, craigslist. Typically $20-30US per "pound". Some of it is NOS, some Dow/Mexico. With an license (30 minute/$30/online/"no fail"), you can purchase it over-the-counter. There's LOTS of R-12 Freon! But get this! 134a is going to be the "new" R-12. New laws restrict 134a use virtually the same ways that R-12 is restricted now. Propane may be the ultimate solution.


Pictures of a '89-? (R-12) truck A/C box:

91yota3.4

Thanks for the pics, but that's not what I need.

Once again, I need to see what a R134a Pickup evap Box looks like. SO 94 or 95. This will tell me if I can just go find a Pickup box and keep the rest of my stuff, or it will tell me that no R134a Box will fit my truck.

Those pics show that that box will fit my truck real nice, but I already know that, I'm looking to put r134a into my truck. Up here R12 isn't an option for me, alright?

anotherjeff

You asked, "...If I find an R12 box will the fittings through the firewall fit the rest of the R134a stuff? ". And, you had the question about the wiring.

duh... I thought the jpgs might help... oh well...

And, since you have failed to compete your Profile, your nationality was unclear. (and i just figured out you have a 3vze by you username) And, it sounded like you were considering an R12 box (see above).
and im just telling you if r12 in canada is like it is here then it ain't a problem, YO?

You need to hookup with someone with 134a Pickup. I do NOT have a 134a PU! However, I am interested in the answer to your query. Maybe I should've lurked.

About the box: Your 134a box appears to have very similar dimensions to my R12 box - hence the jpgs. I'm still not convinced that they are not "plug compatible". (the actual plugs should be the same. The condenser fan is mediated via a fenderwell relay and radiator-support speed control resistor and so isn't connected thru the underdash plug.) Could you be more forthcoming with details of exactly how your 134a box is "too big"? Some pics might help.