the fan shouldn't kick in till around 3/4 on the gauge. once the stat is open you have to wait for the rad to be fully hot all the way across before the fan will kick in. since its bloody huge, this will take a lot longer than it used to
What's the status of this mk3 ac conversion? Is it operation okay? I'm embarking on a similar swap (mk3 tdi with mk3 AC components in a mk2).
Still pending completion I'm afraid. Weather stopped progress last year (driveway repairs because the garage is full of cr4p) and I wanted to confirm plan B was doable. It is just pending pipework electrics and "gassing" Firstly take a look at Rubjonny's MK4 HVAC install. Looks a lot less work than the MK3 since I needed to have a box welded into the bulkhead to allow the MK3 HVAC to fit. @rubjonny didn't the lucky sod . Fortunately I was having the rear quarter panels and sill ends welded at the same time. Not sure why there is a difference but in hindsight I'd go MK4 manual aircon. The next issue is the pipework. VW uses Ali pipework however only the compressor to the condenser and half the compressor to the HVAC fit. The pipework from the HVAC to the dryer and HVAC along the inner wing don't fit with the MK3 HVAC. They might with the MK4 HVAC because it doesn't protrude as much. I went to Pirtek and they were looking at supplying some really thick hose which I didn't want. I then went to Carlton Hydraulics in Rotherham and they showed be Burgaclip, quite neat but expensive and easy to use. So I will make-up the remainder of pipework with Burgaclip (£230). Funnily enough tonight I have been untangling spaghetti....well the MK3 wiring loom. Oh what F.U.N. that was (anagram. Not sure what the U and N stand for!)
Could be.... I'm sure we can all agree on what the F stands for. A word regularly used when doing car repairs especially when things aren't quite going to plan!
Thanks for the update! What box needed to be welded onto the bulkhead? It looks like the MK3 AC evaporator fits into the Mk2 air box no prob. I've been getting my advice and moral support from a builder in North Carolina who has done the Mk3 to Mk2 swap. He has talked me through it pretty well. So far I've worked out the lower radiator support so that it supports the Mk3 condenser and radiator, allowing the lower outlet room for a hose. I put the AC drier on the opposite side of the frame rail (like the mk3, or where the mk2 carbon canister goes), But the condenser to AC line is corroded on one end and not long enough. Hoping I can find someone to make a longer hose, or I can buy another oem line so they can just extend if need be. It looks like the other lines fit. As for electrics, I was actually dealing with the bowl of spaghetti when I saw your reply (stripping the tape off so I can reroute/rewrap). I'm using the whole mk3 harness which includes fan controller and AC system hook ups. Everything is straight forward on that end. In the car is where I'm a little less fluent. But my bud mentioned the resistor pack which I got from the Mk3. And said that if I don't want to use the mk3 AC/recirculate button then I can rewire it into the mk2 HVAC control head. It's nice that the mk3 switch fits snugly into a rocker switch spot, but I do like the OEM look so I may just rewire it into my head. I imagine I will need to use an interior harness specifically for Mk3 HVAC control (which I have). Haven't figured out what from the mk2 setup I'll need vs mk3 for interior harnesses. One unknown element with the mk3/b4 setup is an extra vacuum solenoid controller thats under the hood that I discovered was an HVAC component. I deleted it since I know my Mk2 hvac air box system works fine as is. Didn't quite understand that extra solenoid. ANYWAY, that's where I'm at. Seems like I'll be golden, eh? EH??
the solenoid controls the recirculation flap, the button inside the car switches it on and off. the mk4 manual ac system is simpler, the button controls a motor mounted on the air box whixh does the flap direct. mk2 is way more complex, everything is controlled by a system of vaccum lines from the ac head to all the various flaps on the airbox
@harpy do you have your steering wheel on the wrong side...ie LHD? If you do then I'm sure the HVAC will fit since the bulkhead isn't moulded symmetrically. On RHD cars the bulkhead moulds into the cabin, hence the need for a self-made box to enable fitment. Also @davidut5 has proven that the MK3 pipework fits..... edit on LHD You can link to my pics via the MK2 forum https://www.vwgolfmk2.co.uk/clubforum/index.php?topic=158.msg2163#msg2163
@rubjonny have you made any progress with completing your aircon install? I went on the hunt for a evaporator pipe clamp and was looking at the pipe routing on the MK4. I'm not sure it will fit the MK3 bay.
not yet no, all the pipes go down the driver side. they would be easier to fit a mk3 than a mk2 thats for sure, as mk3 is similar to mk4 with the open chassis leg design unlike mk2 which has plates over the top of the legs. there is a large hole under the airbox for the carbon canister I was hoping I could use but we'll see
I have now bought the Burgaclip fittings so will hopefully trial fit it all this weekend. https://ibb.co/wph59Fz Re the wiring. I really need some direction (idiots wiring guide) with which bits I need to use from the MK3 engine loom and how that would link to the dash switch. I want to keep it SIMPLES and turn it on/off with a switch. I have a MK3 switch but would prefer to "re-purpose" a MK2 one (I have an extra fog lamp switch). From doing a bit of reading it needs to loop into the fan, the outside temp gauge (assume I can use the existing one ?) dryer (which includes a pressure sensor. But what about the engine temp sensor? I've seen a block front flange which has 3 sensors, do I need one of them or just piggy back off the existing black sensor ? If anyone knows someone who can do the wiring that would be good since I don't want to come back to a "real fire".
This is roughly what i did. As you see, not using mk3 fan control relay, or mk2 "rare" ac components. Does not need engine temp sensor, what it had is a coolant switch, at 120deg C open and cut ac compressor. I have it fitted but not wired in yet. I have ambient sensor switch, below 4-5deg c cuts out compressor, in the winter.
@davidut5 Thanks, just remembered you posted that earlier in the thread....How long have I taken?! @rubjonny Please can you share the MK3 aircon wiring diagram for aircon. I had a look though your sig link but couldn't find it. Thanks in advance.
first need to decide how you want to control the fan and ac compressor, the simplest option for retrofit tbh would be use the mk3 fan control module as 99% of the wiring is in the engine bay with just the ac switch on wire running into the bay plus an x-contact ignition live but you could tap into the horn power for that one. The MK2 13 ac relay is another option, these are pretty easy to get hold of but you would be looking at US ebay or China which adds up on the postage costs. I got one cheap from lithuania but that was pre-brexit so these days the postage is a killer from there usually then you need to decide which safety switches you want to include in the system, mostly these are just wired inline with the ac switch on circuit so again pretty simple If you have a complete mk3 engine loom with aircon what you do is start from the ac box, keep every wire that is tapped into it. If you dont want to strip the mk2 loom to add wires back to fusebox you could cut the long red wire to fusebox and crimp a spade on it then it'll plug into the matching wire on the mk2 fan loom plug, use the mk3 fan switch if its different. can make a little inline daisy chain plug for the ignition live to plug into the horn wiring to save cutting any of the original wiring. then use one of the spare grommets passenger side to get your last trigger wire inside the car. Personally I would pull out the lighting loom and strip it down, then integrate. probably find some of the old mk2 lighting plugs need fixing up while there but its up to you ofc the wiring diagram you need is 'g3manualac.pdf': https://drive.google.com/file/d/0B_...=sharing&resourcekey=0-fjul7sFqxlEzxHvnAIxCfw
@rubjonny. Please can you post a pic of your HVAC peeping out of your bulkhead. Then people can see the difference between a MK3 HVAC and a MK4 HVAC. I know I've seen it somewhere Mine is modified to fit the MK3 HVAC https://i.ibb.co/ss1MfyR/MK3-HVAC-Installed-View-from-the-engine-bay.jpg
@rubjonny I must be imagining things. I felt sure I'd seen a pic of your MK4 HVAC install and a smaller hole in your bulkhead?
now you said it I had a think, and found some pics which must have come from another climatronic discussion that I had saved in my reference folder. probably the same ones you're thinking of
