Replace Portion of Low Pressure Aluminum Pipe with Identical Pipe for Air Conditioning System

Hi guys. So recently I posted a question on this forum asking whether or not it would be possible to replace a portion of aluminum pipe from my 1999 Mercury Villager’s air conditioning system with rubber pipe (forum can be found here). After reading all the responses and doing a lot of research, I decided that the best thing to do would be to replace the entire low pressure aluminum pipe going from the rear evaporator (located near the rear right tire) all the way to the compressor (located in the engine). There’s only one problem with that, I cannot seem to find the pipe anywhere on the internet. And even if I do finally find it, it will probably end up being really expensive (I’m on a pretty tight budget).

So as always, I decided to come up with a plan B. Instead of replacing the entire pipe with the manufacture’s original pipe (which I can’t find), why not replace the portion of the pipe that is bad with an identical aluminum pipe? I inspected the entire pipe going from the evaporator to the compressor and its all in really good condition except for the part I want to replace. I can easily buy an aluminum pipe with the same size and thickness from my local hardware store. I also have the proper tools to cut and bend aluminum pipe. The only problem is that I don’t know how to do is properly connect the old pipe to the new pipe. Some websites recommend using an aluminum coupling and secure it with alumiweld. Other websites recommend using an ATP coupling to join the two aluminum pipes.

So that brings me to my question. How do I attach the old aluminum pipe to the new aluminum pipe?

Again, Thank you in advance!

***** Below are the same photos from the original post to help you better understand the situation *****

Picture of how I want to cut the pipe

Another view of how I want to cut the pipe

The Hole

No easy (or hard, even) way to do this. I’d find an a/c shop and see what they’ll charge you. You’re way past the DIY stage for this type of work. High pressures are involved, even on the low pressure side (when the car’s shut off). See what a pro will charge.

Does a Nissan shop anywhere have this part?I know you like this vehicle,but I see rust and She is getting a bit long in the tooth.

Is this it?

The simplest, cheapest way to splice this is to cut the bad part out and sleeve it with a length of A/C rubber hose that should overlap each end by at least 2-3 inches and held on with screw clamps at a minimum. As I mentioned in your first post this means A/C specific hose in the appropriate size and which is sold by the foot…
Trust me; I’ve spliced a lot of hoses this way and made a lot of complete hoses from scratch this way without issues.

That’s as cheap and as bare-bones as it gets.

Seeing as how the leak is down low this contributes more to refrigerant oil loss so that should be taken into account when recharging the system.

Rubber hoses will not seal when slipped over a smooth aluminum hose even with multiple hose clamps. An older AC shop could cut out the bad section and weld in a new section if the parts are still available. Often I have been forced to cap off the lines to the rear evaporator on vans, etc because the cost was so prohibitive. And the incidental costs to replace damaged headliners, etc, adds insult to injury especially when the rear air is not repaired.

I have to respectfully disagree that rubber hose will not seal over a smooth aluminum hose. I’ve done it a number of times with no issues.
With the right size A/C hose and sleeved over the aluminum for 2-3 inches the hose was near impossible to move even with no clamps in place.

About 20 years ago I had a Ford Granada with no factory air on it and built a system from scratch on that one. A Subaru A/C compressor, Ford Falcon evaporator, Nissan condenser, and all of the hoses were homemade from scrap bin stuff including the used rubber cut to fit. It worked great and was working great when I sold the car a few years later.

It’s hard to argue with success @ok4450. I was never so lucky when attempting such connections though.

I do understand what you’re saying about leakage from something like this and do agree. There’s been a few times where I had to revamp one a bit; especially if the repair was in the vicinity of a bend and which then caused the round aluminum to distort and flatten a bit.

Well if you could make a bit of a flare,should seal just fine,using virgin hose.

A “Sharkbite” type connector,wouldnt work for this app,would it?(works fine on high pressure water)