Okay, so I'm in the planning stages of repairing and retrofitting the AC system on my 91 F150 4.9l. I have already purchased a kit that includes new compressor(pre filled with PAG oil), drier, orifice tube, and all o'rings.

I'm figuring that I will also replace the condensor and refrigerate lines due to the fact that in 91 these lines are not barrier style. I found a 95 at one of the local salvage yards that offered the condenser and both lines for about $50.00.

My question...are there any caveats reusing the used lines from the 95?

Part of my plan is to buy a new liquid line for a 91 so that Ill have the proper style barrier hose (about $17 at rockauto) and take it to the shop to have it cut and connected to the line from the 95. This way I'll have the right fittings on each end as the evaporator connection is different on the 94/95.

 

Re-using steel or aluminum lines or sections thereof that have been cleaned out and are not corroded or damaged, and do not have an internal muffler in them, no problem.

I would NOT re-use an old hose when it's getting on 20 years and I didn't have it before. I replaced all hoses and everything on my 1994 Bronco a few years ago when I did a firewall-forward replacement.

Here are two recent threads, I think there are parts from each that you can use if you wish:

https://www.ford-trucks.com/forums/1...-liter-v8.html
https://www.ford-trucks.com/forums/1...6-f250-hd.html

You didn't say what happened to your A/C... did the compressor seize?

 

Thanks, good feedback.

The compressor works, but system needs recharged..which means there is a leak somewhere and possibly other issues. Basically, it cycles continuously on and off, then the clutch begins to make noise, heat up, etc. The truck sat a few years before I got it, I figured it would be best to start fresh and save the cost of filling with R12 (or equivalent) and use the expense to retrofit with R134a parts.

Now, do you also recommend a new evaporator? Would there be a significant reason to replace? Like improved cooling? Or, would just having the right connections be the only reason? I'm sure the shop can reuse the metal part of the liquid line to evaporator on a new line...

 

If the compressor wasn't dying and putting debris into the evaporator, the evaporator is probably OK. But then, if you are going to be replacing just about everything else anyway...
Also - evaporators act like accidental air filters, I've pulled out evaps that are really nasty with fibrous matter reducing air flow through them. If there is even one tiny leak in an evap, the oil film will spread out across the core, and improve its dirt-grabbing efficiency, like the oil-bath engine air filters of pre-1960s. And, how do you know that the leak (or one of the leaks) the system had wasn't the evap?

You did not mention a new accumulator/drier, if its not on your list, you will need one of those for sure. It should be the LAST item inserted into the system before evacuation starts, because once the sealing plugs are pulled off of it, the desiccant inside will start to do its job of absorbing moisture. You want to use its moisture absorbing characteristics when the system is charged up, not use up the desiccants ability just soaking up moisture out of the air or every part in the system before it is evacuated.
The vacuum pump will pull out system moisture, the desiccant keeps it dry over the life of the A/C system.

I assume you are going to use the superior R-134a design condenser from the 1995, right? The only question I would have with it is the junkyard unknown - was it from a vehicle that the A/C was going/went due to compressor failure? Could be hard to tell, and flushing probably won't work properly (mentioned that in one of the threads I linked). A new one will solve that.

Any crud lodged anywhere can come loose later and kill a new compressor, and compressor warranties have become very specific as to the minimums that must be performed and documented prior to use. For me, the cost of using new parts is less than the cost of disaster and doing it all over again with a set of different parts.
I like to do things once

Here in TX, we DON'T want to be without A/C, it's versus

EDIT - Oops, just re-read your first post, you HAVE a new acc/drier, good!

 

I'm still needing some additional parts before I start replacing stuff...

Have a question: A condenser for a 94 has female #8 o-ring type fitting on the outlet...I'm assuming this is where the suction line connects?

If so, then a new liquid line for a 91 would suffice. I contacted the manufacturer (Murray I think it is for part number 55712) and they confirmed that the replacement hoses are compatible with R134A. So, no need to buy a liquid line for a 94 and modify.

Now, it's my understanding that a 94 hose assembly (compressor to condenser/evaporator) will work with the 91 evaporator too.

 

Update/correction:

The condenser on a 94 has a female #6 o-ring fitting on the liquid line side (still not sure if that is suction or discharge ) ...so I'll need a custom hose to work with my 91 Evaporator (91 evaporator has #8 female spring lock where as the 94 used a #6 spring lock)

I ordered exactly what I needed from Coldhose.com. I called them this morning...they answered on the first ring and knew exactly what I needed.
purchased a customer #6 barrier style hose with a #6 male insert o-ring on one end and a 45 degree #8 male spring lock fitting on the other. $43.00 including shipping.

I'll try to get some pictures posted once I get started.

BTW, this may be common knowledge but, Male insert o-ring fittings mate with female o-ring fittings. It took some research as there isn't a lot of detail on a/c fittings and the proper style that each connects to out there. I mean, there is tons of fitting specifications but none that speak to male insert o-ring and regular male o-ring compatible fitment.




Male o-ring





Male insert o-ring

 

Just wanted to update...the A/C swap is done. Very good results I think.
100 degree ambient temps here in SC lately. Approximately 60% humidity.. Been getting upper 30's to low 40's from center vent. In the evening I'm getting below freezing temps in the evaporator and may have to adjust LPCS. But, for now am very happy with the results.

Anyone interested in details or pics...I can elaborate but failed to take many pics during the process. However, I'd be happy to help anyone out, or provide more information if needed.

I've started another thread concerning air deflectors...as this thread was more specific to the refrigerant lines.