1987/1993/1996 Bronco AC upgrade...

[slawson2000]

Once upon a time

Where do I begin ('87 Bronco / R134A) https://www.autoacforum.com/messageview ... adid=17222

Tell me if I did it.... https://www.autoacforum.com/messageview ... adid=17615

Brings me to the current situation. I am currently upgrading the engine from a 302 to a 351 and that necessitated switching to a newer style compressor, which led to other things. One of those other things is a parallel flow condenser from a 1995-6 F-Series/Bronco. It fits fine, with one exception. The connection from the condenser on the passenger side. See the attached pic. The existing line is a bit short and the fitting it the wrong size. Not exactly sure how to measure/describe the two. But the condenser fitting on the drivers side would match up to to the line on the passenger side.

Is there some adapter that I could use to fill up the gap and connect the two? Maybe even remove the adapter that is there?

My other thought would be to get a rigid line from a 95/96 and braze a larger end from the 87-93 to where it would attach to the accumulator/dryer.

Thoughts?

[bohica2xo]

Wow. A true blast from the past. And 13 years later you are still driving the Bronco!

Time to have a new liquid line made up to run from the new condenser to the OT connection at the evaporator.

All Hose on Post Road in Las Vegas can do the job if you are still here in town

That brass fitting stack in your picture is one of Ford's mystery dry break connectors. Randomly appearing on various models across 20 model years. If can be removed from the system. We always guessed it was for sweep charging on the assembly line. Sort of like the plastic plug in the C6 transmission pan...

Good to see you back

B.

[slawson2000]

Hey B.
Yeah I love the old truck. I have had it almost 30 years now. I send a lot of people this way for solid info. Thanks for being here.

So while I am here, where could I find the specs for the 1993 system? (amount of oil and charge).

Would they have the parts or should I do what I was thinking and grab a newer rigid line and get a new end put on it?

Also, what ends am I looking for?

[bohica2xo]

Oil & refrigerant charge specs here:
https://www.techchoiceparts.com/refrige ... ight-truck

Note the volume shift when they went to 134a - this reflects the shift from Tube & Fin to serpentine / parallel flow condensers which hold less volume (and expose more of it to airflow)

As far as the hose ends go, I have never been able to stump them. They even managed to match 1965 vintage Plymouth brake fittings for me.

The easy way to avoid confusion is to provide them with a sample fitting. Either take the condenser with you, or an old hose end that fits. They can match from either side of the joint.

If you have a rigid line that fits, they can probably add the proper hose to it as well.

[slawson2000]

That's a good link.

I am a bit confused though and I might not have it right but...

93 and down - R12 - had a tube an fin condenser and some cans on the suction and discharge line. Not sure what those cans are for.
94-95 R134 had the parallel flow condenser, did away with the cans on the line and got a compressor to match.
96 had the same setup as 94-95 with a different compressor (not sure the difference).

Also, looking at the specs, it seems the 95 Bronco oil is high (11oz) compared to the 95 F-Series (7oz).
The Bronco and F Series used the same parts.

Why did 96 get so much more refrigerant?

Also, since my setup will have the 1993 compressor (R12), cans in the hose, parallel flow condenser, and running R134A - where is a good place to start?
7 to 8oz oil
32oz refrigerant
Maybe by pressure?

[bohica2xo]

The 96 is a mystery to me too. But in those years there was still Dealer installed A/C with an SD709 compressor on some trucks (I have one) So perhaps that reflects that. Or perhaps rear A/C? Just like the random dry break connectors - say Ford, shake your head and move on.

Your plan for 7+ ounces of oil sounds good. Replacing the line with the "cans" is also very possible if you want to - they are not reasonable to flush.

You have another version of the custom system you had 13 years ago. Charge it just like you did in that thread:

https://www.autoacforum.com/messageview ... adid=17615

Except a pressure ratio of 2.5 to 2.7 x ambient is more in line with the Parallel Flow condenser you have now.

[slawson2000]

Makes sense on the charging.

So what are those "cans" on the hose? Filters? I am not necessarily a fan of them, but they were on the hose that fit.

[slawson2000]

Mufflers? Never would have thunk.

Mine are bigger.

s-l1600 (2).jpg (16.03 KiB) Viewed 11219 times

[slawson2000]

Also have another question. What seal is up in there? Is it an o'ring?

This is the added high pressure cut off switch that was added with the R134 conversion. It installs on the high pressure line port.

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20200410_120104.jpg (68.41 KiB) Viewed 11212 times

[bohica2xo]

Enough with the noise stuff.

Mufflers are a trash trap on a system with a failed compressor. We re-plumb & toss them all the time. On vintage restorations I bore out the tubes in the can, add a straight through tube and braze the can on as a decoration. Plenty of Mopars that way now.

Besides, that Bronco makes enough of a rumble to cover up a failed idler bearing anyway.

I think we could make better cars if we fired half of the NVH staff, and beat some sense in to the other half. I think the guy that invented the liquid filled engine mount should be burned at the stake.

Ok, back to A/C. The seal in that fitting was probably an O ring. I will have to go look and see if I have an unused one to look at and be sure.

If you have a new hose that fits, and has cans in it, no problem. If you are rebuilding hoses, delete them.