Reinstating Air Con

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super
Posts: 169
Joined: Fri Dec 17, 2004 4:17 pm
Location: Essex

Reinstating Air Con

Post by super »

Hi,

Has anyone managed to reinstall AC on a car it was removed from before?
A fair you years ago I removed it, which I now regret.

Cheers,

John
yokomomr4bx
Posts: 213
Joined: Sun Jan 20, 2013 3:06 pm
Location: Cardiff

Re: Reinstating Air Con

Post by yokomomr4bx »

Finally someone else living this pain. I also removed my system years ago and I am currently re-installing it. I'll have a full tutorial on my build thread in about 2/3 months time but my advice for the time being would be to source a compressor/pump and the associated bolts, idler pulley and bracket and the long pipes which run front to back of the car. Hopefully you didn't remove or destroy the connections inside the frunk which run into the matrix/have the high pressure port etc? What other parts of the system do you have? Was your car fitted with R12 or r134a gas - the pipes are definitely not compatible despite following the same routing (r134a is a much 'smaller' gas the R12 and consequently the connections and O-rings are completely different). Below are the comparisons between R12 and r134a seal specs:

Image

If you end up cutting those pipes around the crossmember at the front (because the connections are corroded beyond return, my advice would be to preserve the long pipes and they're associated connections to the compressor all intact - do not try and separate the long pipes from the runs which go into the compressor (you need to keep any pipes whcih come out of the compressor as long as possible before you start custom building. You will be able to braze on new connections to the cut pipes using parts from the kit I've attached a link to below. I explored having fittings welded directly to the pipes but no pipe shop, aluminium welder or AC specialist wanted anything to do with this. Welding on a thread also limits your 'clocking' of the pipes and the type of pipe you can use. As a rule most -8 and -6 AC pipe (which is the dimensions of our system) are quite stiff, bulky and make routing difficult. The hose used for the system I've given the link for is much more flexible and of a smaller diameter, and the ability to clock the pipes as you like when building is a huge bonus.

https://www.t7design.co.uk/air-con/air- ... pares.html

I haven't yet decided on the condenser to use - there may be the possibility of sourcing a genuine one from MR2-BEN at the end of August. However these are expensive. A comparable volume condenser from any other brand would be at least half the price. And if you have already got used to the EZ-clip system, it really isn't too much effort to go the whole way and fab up pipes to take you into any condenser you like (whether you keep the stock drier is also up for debate). Custom brackets and high pressure switch port is a given at this point. This is the last phase I'm working through at the moment and as I said I should have a full re-build/build post for this in a few months.
yokomomr4bx
Posts: 213
Joined: Sun Jan 20, 2013 3:06 pm
Location: Cardiff

Re: Reinstating Air Con

Post by yokomomr4bx »

Just to follow up on this...replying to your post prompted me to check the cross references of OE part numbers with DENSO part numbers (the OE manufacturer of the entire system). The OE part number for r134a gas systems is 88460-17080 (change this last number to 17060 if your system is R12). This part number cross references to DENSO 477-0534 (0110 if R12). You can currently purchase this from the states (as I have just done) for £260 including import tax and shipment. This is actually at least £100 cheaper than MR2-BEN is currently offering them for. Here are the links to DENSO's catalogue:

https://www.densoproducts.com/denso-477 ... -condenser (R12 gas systems)

https://www.densoproducts.com/denso-477 ... -condenser (r134a gas systems)
jimi
Posts: 2095
Joined: Tue Dec 14, 2004 10:27 am
Location: Kingdom of Fife
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Re: Reinstating Air Con

Post by jimi »

Worth bearing in mind you can't get R12, it's no longer manufacturered and id banned. You can still run a system containing it, but it's not legal to sell or offer it for servicing purposes. Most cars after 1992/3 will be R134a, there's ( or there used to be) conversion kits available.
R134a is a common replacement for it, but it's not a "drop in" replacement, usually runs at different pressures, so the pressure switches need setting up to suit and usually the expansion valve needs replaced. On cars the service valve fittings are normally different on R12/R134a systems to restrict the chance of putting the wrong gas in.
I believe there's now a direct "drop in" replacement for R12, its a HFC blend called R426A (RS-24)
Rob66
Posts: 620
Joined: Sun Dec 26, 2004 10:12 pm
Location: Sussex

Re: Reinstating Air Con

Post by Rob66 »

Thanks for posting. My UK Rev3 has the rare Factory A/C option and I am looking to get it working again R134a.
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