Retro fitting A/C?

[sheriff464]

Hello LEC, Is it possible to retro-fit air conditioning to an S2? Has anyone done this? and what would be the likely cost of such a conversion? Any thoughts on this subject much appreciated! Cheers from Sheriff 464.

[Brit-Car-Nut]

You can always fit or retro-fit just about anything to any car but the cost of parts and LABOR will be astounding. I would guess that IF you could find all of the mounting bits, the plumbing, electrical and a good compressor, condenser and evaporator, it could be done, but most of the parts are long obsolete. You would probably have to find a donor car to get everything you need and then install them in your car. You would be looking at a huge investment.

The best way to install would require clam removal, facia removal, radiator area removal and routing all of the plumbing would be daunting at best. I believe Phil retrofitted an AC system a while back as the compressors were dirt cheap but he was rebuilding the car so it was mostly disassembled. Hopefully, he will join in and give his point of view.

I would guess you could spend several thousand £ to get an OEM system installed without doing the work yourself, and since most of the oem parts are no longer available, you will spend a lot of time on fleabay and at breakers getting everything you will need.

You could possibly find an aftermarket A/C company that can make up a kit for you but I doubt it will be cost effective. They used to make an A/C kit for the MGB and the Marina, so anything is possible.

[sheriff464]

Hello,thankyou for your reply Brit-car-Nut. So looks like cost would be the most prohibitive factor ; add onto that the amount of time it would take to source all of the required parts! Looks like I will just have to keep the top down and the speed up!! Cheers from Sheriff 464.

[Simon_P]

In answer to your questions.
Yes
Yes
About £1000 but finding some of the parts will be tricky.

No need to remove the topshell, just the bumper.
No need to remove the Dash, just the glovebox and loosen the heater fan. That said it would a lot (x10) easier if you did remove the facia, but that is a bit involved for doing up 4 screws.

It's nice on long hot journeys, but the real reason I fitted mine was for demisting the windscreen on cold wet days.

[Brit-Car-Nut]

Sorry Simon. I knew one of you retrofitted a system a few years back, I just didn't remember who.

For the FED car, it is much harder since it has a different nose and the glovebox is on the wrong side...

I believe it also requires changing the heater control and associated vacuum lines. Did a lot of the M100s in the UK have air conditioning? I believe ALL of the Fed cars did.

[Simon_P]

Hi John,

I hope you are well.

Yes you have that extra frame, whereas the UK version only has 2 extra bolts to hold the condenser in, so its just remove the radiator frame and the bumper to get at the whole lot.

Putting the evaporator in is by no means easy, as it overlaps the fan... then there are the 4 self tapper that hold it to the cross brace, you obviously can't see them, you can't feel that they are aligned, there is only just enough room to get fingers in between the dash and the cross brace, there is no room for your arm... whilst cramped in the footwell you have to position and tighten 4 screws that are held between the sides of 2 fingertips. If anyone is trying this it helps to run the self tapper in the holes first (but you could of course try without!)

The S2 has the recirculating heater control as standard
I think all of the wiring looms have the required connectors, and the ECU does the logic as standard - so its just plug and play

[Fetnas]

I've actually started going down this path. In my case I picked up an evaporator and AC switch from aftersales before I shipped the car to Aus. Everything under the bonnet is not Lotus. The condensor is from a tractor, the only one I could find that was about the right size, although a bit wider and fouls the front bumper. Need to trim a little off on the inside of the side air ducts to the oil cooler and the charge cooler.

My dad did most of the work, it helps that he worked for GM and was an AC research and development engineer. He designed a clever mounting bracket for the compressor that included an idle pulley allowing more wrap around the compressor and crank shaft pullies, and it incorporated a screw driven tensioning system for the power steering pump to get the belt snug. It has a compressor from an early 2000 Astra which I believe has a self regulating variable displacement for greater efficinecy.

The car hasn't been used much recently so the incentive to finish the work hasn't been high, but it should only take a bit of wiring, fitting the evaporator and filling with gas. I would have struggled to do this without my dad's help.

[Karozza]

I've actually started going down this path. In my case I picked up an evaporator and AC switch from aftersales before I shipped the car to Aus. Everything under the bonnet is not Lotus. The condensor is from a tractor, the only one I could find that was about the right size, although a bit wider and fouls the front bumper. Need to trim a little off on the inside of the side air ducts to the oil cooler and the charge cooler.

My dad did most of the work, it helps that he worked for GM and was an AC research and development engineer. He designed a clever mounting bracket for the compressor that included an idle pulley allowing more wrap around the compressor and crank shaft pullies, and it incorporated a screw driven tensioning system for the power steering pump to get the belt snug. It has a compressor from an early 2000 Astra which I believe has a self regulating variable displacement for greater efficinecy.

The car hasn't been used much recently so the incentive to finish the work hasn't been high, but it should only take a bit of wiring, fitting the evaporator and filling with gas. I would have struggled to do this without my dad's help.

Hi Fetnas, I know this is an old topic, but did you get it work & is it reliable?

[Fetnas]

Hi Karozza,

The short answer is I haven't found the time to complete this installation. There's no reason why this install wouldn't work, as prototyping these systems was exactly what my dad did during his career. That said, he did state that this system is only likely to be a spot cooler, and won't cool the entire cabin down. He would know as he was lucky enough to to the thermal test drives of the M100 in Death Valley back in the late 80s.
Life has got in the way of completing this install, which is probably 80% complete. The main things left to do is install the factory evaporator under the dash, install the receiver dryer, do the electrical connections (I have a factory AC switch) and put a gas charge in it. But having 2 small children to entertain, makes finding time to do this very difficult.

If you have any specific questions, let me know and I'll try to answer them for you.

[Giniw]

He would know as he was lucky enough to to the thermal test drives of the M100 in Death Valley back in the late 80s.

Wow, nice!

[Fetnas]

Hi Giniw,

I've uploaded some of these photos to the 'Former Lotus Employee' page of the forum previously under the title Photos from 1988 testing a development elan in Arizona', feel free to check them out if you haven't already seen them.

[Simon_P]

He designed a clever mounting bracket for the compressor that included an idle pulley allowing more wrap around the compressor and crank shaft pullies, and it incorporated a screw driven tensioning system for the power steering pump to get the belt snug.

please could you share details - That would be really useful as it is a beach to try and get enough tension and it would be greatly improved by more belt wrap.

[Fetnas]

Hi Simon,

My dad did some rough CAD modeling of the engine block mounting points for the compressor bracket and then CAD modeled the bracket itself. I'll have to see if the design is still on file somewhere. I'm not sure if it will work with the factory compressor, he was working around a compressor from an Astra G as he was very familiar with those.
Due to the tight packaging in the engine bay, it's almost impossible to get a photo of the installed bracket.
If I can find details, I'll upload something.