Air conditioning line routing

[Blaise]

I am in the process of re-assembling my air condition system (engine side) and need a little help with the routing.

I had the three flex lines rebuilt, am installing a new drier, had the condenser checked and am installing a new expansion valve.

The larger of the flex lines seems simple, as it can only go from the compressor to the fill valve (which then goes through the firewall).

Then there is a smaller line from the compressor to the condenser. Does it go to the upper or lower connection on the condenser?

Finally, to go from the drier to the condenser, there are two lines. One flex and one rigid copper. Take a peek at my photos and let me know if I did this right. Much appreciated.

The routing of that line seems awkward to me. Also, I would think that one would want the copper line next to the exhaust, rather than the rubber flex line.

I take lots of photos when I take things apart, but I seem to have missed this system, hence my need to ask. I have manuals, but they do not give me enough specifics to answer this. Also, one manual (factory) shows the routing to the condenser one way, and realoem shows it opposite. Maybe it does not matter.

By the way, my rebuilding of the flex lines was in three parts. I welded and soldered barb fittings (purchased from A/C shop) to the existing fittings ($20). Then had the A/C shop install the flex line ($40), but not crimp them. Now I am getting the orientation correct and then will have them crimp the lines.

<table><tr><td><a href="https://picasaweb.google.com/lh/photo/Z ... site"><img src="https://lh5.googleusercontent.com/-ogrZ ... G_2131.JPG" height="300" width="400"></a></td></tr><tr><td>From <a href="https://picasaweb.google.com/1030509870 ... bsite">E12 air conditioning lines</a></td></tr></table>

[Blaise]

http://www.realoem.com/bmw/diagrams/e/v/21.png

Assuming that this is correct (from realoem), then I think I have it right. I did find a photo of my parts car that shows the copper line along the chassis rail.

[Robert Bondi]

I am in the process of re-assembling my air condition system (engine side) and need a little help with the routing.

I had the three flex lines rebuilt, am installing a new drier, had the condenser checked and am installing a new expansion valve.

The larger of the flex lines seems simple, as it can only go from the compressor to the fill valve (which then goes through the firewall).

Then there is a smaller line from the compressor to the condenser. Does it go to the upper or lower connection on the condenser?

Finally, to go from the drier to the condenser, there are two lines. One flex and one rigid copper. Take a peek at my photos and let me know if I did this right. Much appreciated.

The routing of that line seems awkward to me. Also, I would think that one would want the copper line next to the exhaust, rather than the rubber flex line.

I take lots of photos when I take things apart, but I seem to have missed this system, hence my need to ask. I have manuals, but they do not give me enough specifics to answer this. Also, one manual (factory) shows the routing to the condenser one way, and realoem shows it opposite. Maybe it does not matter.

By the way, my rebuilding of the flex lines was in three parts. I welded and soldered barb fittings (purchased from A/C shop) to the existing fittings ($20). Then had the A/C shop install the flex line ($40), but not crimp them. Now I am getting the orientation correct and then will have them crimp the lines.

I rebuilt my system as R134a 5 years ago (everything outside the firewall).

A couple rules of thumb to check:

1. The E12 condenser is a little weird because both connections are brought up high. In general, the condenser inlet should be on top and a bit fatter than the bottom because the incoming gas will occupy more volume. The bottom outlet connection should be smaller in diameter - the condensed liquid will naturally drop to the bottom.

2. Compressor outlet should feed the condenser inlet - the compressor has to be on the gas side of the system.

Does the top condenser line in the realoem drawing actually originate from the bottom of the condenser? My input above would make sense if that is the case.

The colored valve caps suggest you are building a R134a system?

Your car looks pretty sharp.

Robert

[Blaise]

Thanks Robert. I pretty much routed it just like the realoem diagram, as it was the only way that the existing angles would work.

As for charging the system, I think it may have been converted to 134a fittings in the past. But, I have been told that sticking to R12 or freeze12 is a better option. I have not really decided one way or another, as I was just replacing the worn parts for now.

Am I committed to 134a with those fittings?

[Robert Bondi]

Thanks Robert. I pretty much routed it just like the realoem diagram, as it was the only way that the existing angles would work.

As for charging the system, I think it may have been converted to 134a fittings in the past. But, I have been told that sticking to R12 or freeze12 is a better option. I have not really decided one way or another, as I was just replacing the worn parts for now.

Am I committed to 134a with those fittings?

Blaise,

I think your routing is correct. I pretty much have the same stock routing. My only deviation is at the non-stock condenser, which has definitive top/bottom connections.

Yes, whatever fittings you choose will basically commit you to that refrigerant. I think even Freeze 12 has its own unique fittings. It's a huge no-no to mix, so unique fittings attempt to eliminate accidental mixing.

You have R134a fittings. Good news is that you could go back to R12 if you wanted. Those R134a fittings, like mine, are just adapters on your stock R12 fittings.

Robert

[Luis A.]

Blaise,

I see on the photos that you have applied some tar board style sound insulation in the engine compartment. I don't see them in the OEM catalog as available. What is the material you used? It looks great.

[Blaise]

Blaise,

I see on the photos that you have applied some tar board style sound insulation in the engine compartment. I don't see them in the OEM catalog as available. What is the material you used? It looks great.

Luis,

When I brought my car to my body shop, they asked me if I wanted them to replace the insulation. They said that they could match what was there. They made patterns of the old and did a great job replicating it. The only thing that I did differently (than stock) was not to paint it. I sent them an e-mail asking what it is and will let you know if I hear back.

Blaise

[Luis A.]

Hey Blaise,

I delivered my car to the body shop last week and expect to be going over details with them next week. Did you find anything about the source of those tar sound deadeners your shop applied? Thanks!

[Blaise]

Hey Blaise,

I delivered my car to the body shop last week and expect to be going over details with them next week. Did you find anything about the source of those tar sound deadeners your shop applied? Thanks!

Sorry, I did not hear back from them. I can try to phone them next week.

[Blaise]

Blaise,

I see on the photos that you have applied some tar board style sound insulation in the engine compartment. I don't see them in the OEM catalog as available. What is the material you used? It looks great.

Luis,

I finally figured out what they used.

It is called Q-Pads, by Evercoat.

http://www.evercoat.com/productDetail.aspx?pID=50

Hope that helps,

Blaise

[Luis A.]

Blaise,

That looks like a perfect replacement for the factory tar pads. Looks like 117 is 3mm thick, pretty close to factory thickness. Thanks for looking that up.