Rebuilt the heater A/C unit. I decided that I would loose the old 70s A/C components except for the evaporator in the heater box. That way should I ever decide to go with a Modern A/C system at least that is there.
I cleaned and tested the evaporator with a pressure check and vacuum down, it seems fine. I removed the TXV and plugged the hoses, then filled it with nitrogen to prevent any corrosion. The heater core was also tested and seems OK as well.
replaced most of the pop rivets with screws to make access easier next time, (which I hope is never!) All flaps were checked and new seals inserted. The A/C thermostat is shot, but I found a replacement that with abit of modification should work, I also found a new TXV.
All of the vacuum components seem Ok but its difficult to say at this point. I found out that the A/c Model has a special 3 position fan switch that is not listed anywhere, and I do not have one.. more on that later!
I plan to use an electric water pump (A Craig Davis pump was secured as a Christmas pressy!) I used core plugs to seal off the old Water pump. Also got a 16 inch electric fan as I plan to eliminate the mechanical fan, it will be controlled by the Crag Davis unit. I'm not 100%
sure how this will go together yet, there is not much info on LHD conversions, many seem to move the alternator but I have A/C compressor so that will not fly. I would like to have the fan as a puller but not sure if theres enough room there until I get the engine in.
Got the Mark2 pulley and how wrong I was. The smaller fan and clutch that I assumed was a Mk1 was in fact a TR7 item, the proper Stag fan and clutch was a MK1 and is in good working condition. The Mk1 pulley has a cut end that fits nicely into the clutch, the mark2 pulley is the same but sits about 1/2 inch further forward.
The pulley I got with the MK2 is neither one or the other. Problem is that the MK1 pulley has a lot of rust and I'm worried that it will wear the fan belt through so I have given the inbetween pulley to the machine shop to turn it down into another Mk1 pulley and I'll use that one.
All this because I have decided to leave the stock fan in place initially, word is that it helps circulate air around the engine compartment and helps keep the engine bay temps down when an electric fan is used. I will make a decision on the electric fan and its size later.
Picture below shows the MK1 on the right (a mk2 looks exactly like that but is as tall as the black one ) and the black unknown "kinda mk2" on the left.