Caledonian Posted 10October, 2017 Report Share Posted 10October, 2017 I'm not really looking for a debate on the good,bad and ugly of air cooled IB 911 air conditioning. There is plenty of that on here and the rest of the inter-web, if you haven't already read it I'm sure you will at some point if you have no AC and or the desire to have some. Just thought I would share what I'm doing, what I've done and what I'm hoping to do to get my AC working again. A brief background for those who don't know me or my car. A 1978 911 SC with factory air conditioning, that did work (slightly) and briefly when I first got the car. A regas did improve things for a while but the worn out and leaky original York compressor was well past its best. My original plan (like I ever have a plan) was to fit one of or part(s) of those aftermarket kits, once the budget was available. Now after nearly 5 years of Brisbane summers later I now know what SC stands for "Sweaty Car" and have decided No more!I'm well aware that without megadollars to cover my car with extra condensers, vents etc. I'm unlikely to get the AC performance of late model Japanese car. So I've not set my expectations too high which is a good job as neither is my budget.l looked at and researched the US AC kits available from the three main suppliers, but it looks like Griffiths air-conditioning is the only one still operating? they do have a kit that would have met the majority of my needs that was within budget (ish), until I added on the freight, duty taxes and transaction fees.There's no argument, to simply buy all the bits you need and fit them would be the most convenient option. Just to clarify when I say "fit them" I mean do it myself....The demographic on this forum has significantly changed since I joined, but I'm still in the minority of those who has to do the work themselfs as I can't afford to have a greasy chap do it for me, while I drive around in my other Porsche (s)?After nearly shelving the project (again) I have persevered with a new plan (well kind of plan) and have actually started work! I had previously bought a new Sanden 507 compressor, Renaire alloy adaptor, and a new motor for the front condenser blower. Unfortunately the blower fan did not come off the old motor very well and will need replaced. A set of Barrier hoses will be required as the old ones are very hard and brittle, probably leaking too? I have a reputable auto electrician/AC guy that will make up a set of hoses at a competitive price, and the drier can be sourced locally for around $50.I've started fitting the compressor and alloy mount, which does require some modification to fit and be adjustable on the original Compressor mounting. It's a bit of trial and error and I am probably 95% there, need to get a new belt to get the alignment right then the next stage is to remove the hoses (in one piece hopefully) so they can be copied. I will have to order a new motor/fan assembly for the front condenser blower, as I have not been able to find a supplier of the fan wheel only. Anyone want to buy a new Bosch condenser fan motor? The option to upgrade the evaporator and its blower motor, along with an upgraded front condenser is the desired next stage. This would give me a more reliable system and probably more effective if you believe all the hype.To be continued https://www.flickr.com/photos/152710446@N03/shares/r25685 Link to comment Share on other sites More sharing options...
Coastr Posted 10October, 2017 Report Share Posted 10October, 2017 I think if you fit a new compressor and new hoses and get everything buttoned up nicely you might be surprised. I would hold off on the extra condensers and look at cabin airflow as the first priority. With a new blower motor and perhaps a Griffiths 'bow tie' center air vent you'll be at a good starting place.having a white car is a good first step anyway. Link to comment Share on other sites More sharing options...
Ozvino Posted 11October, 2017 Report Share Posted 11October, 2017 I know its apples and oranges (928 v 911) - I replaced the compressor and hoses on my 928 along with having the blower unit serviced and the difference was amazing; in the past the gas was slowly leaking, its now better than new and freezing at the vent. I suggest getting the refurbished stock setup in place and see how it performs. Link to comment Share on other sites More sharing options...
Caledonian Posted 11October, 2017 Author Report Share Posted 11October, 2017 I think if you fit a new compressor and new hoses and get everything buttoned up nicely you might be surprised. I would hold off on the extra condensers and look at cabin airflow as the first priority. With a new blower motor and perhaps a Griffiths 'bow tie' center air vent you'll be at a good starting place.having a white car is a good first step anyway. If it was not for the fact that I have to order the front condenser floor fan from the US (Griffiths), that was what I originally was going to leave it as you said. Unfortunately the Bow tie vent is not an option on the RHD but Griffiths do you offer similar vents that connect to the side slit Vent holes that might be an option.Did you fit a bow tie ventto your being a LHD? Link to comment Share on other sites More sharing options...
Big Dav Posted 11October, 2017 Report Share Posted 11October, 2017 I was in the same boat with my 87 3.2 which had all the factory AC gear but didn't work when I got it 18 months ago. Lots of reading and watching Youtube videos got me fired up to try to fix it myself. My idea/plan was to try to get it running with the standard gear and then replace bits as needed rather than buy a big kit of stuff and throw new parts at it. I know that these systems were never great but I thought I'd give it a try. I live in a cooler area of Australia and not in the city (no stop start driving) so I figured if it was going to work anywhere it would work here.The compressor was visibly leaking and replaced with a rebuilt unit from C.A.R. in Keysborough, Melbourne. I flushed all the lines and condensers with AC flush solution and oiled and replaced every O ring I could get to. I didn't flush the evaporator (just a vacuum of the outside dust) or TX valve. Mine already had a hi/lo cutout switch fitted to the system. I purchased a vacuum pump and manifold gauge set on ebay. The guy at C.A.R. recommended Hychill Minus 30 gas as well as their mineral compressor oil - He reckons that conversion to R134 has paid for his retirement as the higher pressures kill these old compressors and will double the compressor warranty if you use Hychill.Compressor oil was added into the lines and a new receiver dryer fitted just before it was sealed up. I pulled a vacuum for three hours and left it for a week without any loss on the gauge so I figured it was ready for gas. I pulled vacuum for another two hours before re gassing with 400g of Hychill. It worked too well initially giving vent temps below zero on my first drive which turned out to be the temp switch/ thermostat not working causing the evaporator to ice up. Also the fan on my front condenser was not working (melted) so both these items were replaced and and inline fuse used on the condensor fan. Six months down the track it hasn't leaked away and still works a treat but I will have to wait a while for a 30C plus day to really give it a test. Total cost including compressor, tools and consumables around $750 but any subsequent re gas will only cost $42 for a can of Hychill as I have all the gear required now. Yes it's not in Brisbane and it's a later 3.2 with bigger vents etc but it works and certainly makes the car more enjoyable and usable. Link to comment Share on other sites More sharing options...
Coastr Posted 11October, 2017 Report Share Posted 11October, 2017 If it was not for the fact that I have to order the front condenser floor fan from the US (Griffiths), that was what I originally was going to leave it as you said. Unfortunately the Bow tie vent is not an option on the RHD but Griffiths do you offer similar vents that connect to the side slit Vent holes that might be an option.Did you fit a bow tie ventto your being a LHD?no I haven't but you can feel the wasted airflow down there that goes nowhere in particular.If you are pulling out the Evap and blower motor take a look at all the gaskets and seals along the air path and make sure you're getting every bit of cool air it is generating. A lot of cars have leaks in the air and a bit here and there makes the difference on what is a marginal unit.i used my AC this morning as the humidity was off the charts and in 1km the cabin was at a nice temp. This is with vent temps at about 14 degrees which is the best I can do currently. If you can get vent temps below 5 or 6 and your fan is working well it will deal with the humidity ok. It probably will need some time to cool down a heat soaked car but going right out of the garage you will really notice the difference. Link to comment Share on other sites More sharing options...
Caledonian Posted 11October, 2017 Author Report Share Posted 11October, 2017 As I mentioned previously, the Renaire alloy adaptor bracket needed some modifications as it fouled the rear support for the main compressor mount.https://www.flickr.com/photos/152710446@N03/shares/1PqZJ4I found reference to this required adjustment in a few posts and a YouTube video, and not just for the Renaire one. I suspect theses mounts are more of a universal item than 911 specific, as the York Compressor was fitted to many cars of that era. There was only so much I could noctch out of the alloy without weakening it, so come off the support stay also.i picked up a new belt today to check the alignment off the pulleys. The only reference I could to the belt size was in a few posts that mentioned the same on as with the York compressor was fine. Only problem is there is 2 options, 13A1100 or 13A1200 and I have went with the one they had in stock 13A1000 and it was too short! This resulted in the compressor fouling of the intake manifolds slightly https://www.flickr.com/photos/152710446@N03/shares/4rV7Lq Once I get the correct drive belt the job will ( well this part will be done ✅ ) too be continued . Link to comment Share on other sites More sharing options...
SimonN Posted 12October, 2017 Report Share Posted 12October, 2017 From my own personal experienceI would go with Hychill. The best thing is you can re-gas yourself. Rather than buy the small cans fro $42, I bought a big bottle for $165 which gives me 10 refills.You can keep the system looking standard without extra condensers. What you need is modern versions of what is already there. I replaced the condensers and evaporator with modern equivalents. An upgraded evaporator fan is a must. You do not need new hoses unless yours are seriously f#^ked. As I did it as a DIY job, I decided to risk a single recharge of gas (cost in bulk of $16.50) to see what leaking I had, despite fairly average looking hoses. i renewed the o rings on everything and flushed properly and now 18 months later, I haven't yet needed to recharge the system. This is probably helped by Hychill which doesn't leak through the hoses in the same way that other gasses do.Don't expect the new, modern evaporators and condensers to fit perfectly. they need a bit of fiddling.It's dirty work!Fit a hi/lo pressure cut out switch. This will save your compressor and is a serious shortfall of the original systemDon't forget to change the receiver/dryer.At the moment, i have the standard early 3.2 type air vents. Even with this, on a day when it reached 36 degrees, I never saw higher than 25 degrees in the cabin although I admit to not having sat in heavy traffic. I will improve the vents when I find the right product that looks original. The system I have will manage bigger vents and I believe that is all you need on top of what I list above. Link to comment Share on other sites More sharing options...
Caledonian Posted 12October, 2017 Author Report Share Posted 12October, 2017 Simon, good to hear another success story with Hychill, I did consider it along with the DIY re-gas equipment but ended taking the road I'm on. Impressed that you took on the job,so many people treat air-conditioning as a dark art, and saying that I would not be so impressed if you are a refrigeration engineer during the day? My hoses are truly past it, if I was using the same compressor I might have tried them but I have to put new fittings on for the Sanden compressor and they are so hard and brittle I doubt if they would crimp properly on the hose.A new dryer with binary (Hi/Lo) switch is on the list and is being sourced locally, and I'll take your advice on the Evaporator motor upgrade as this seems to be the consensus.Did you get the Griffith one?Do you have any pics of the condensers you fitted? Link to comment Share on other sites More sharing options...
Glom1098 Posted 12October, 2017 Report Share Posted 12October, 2017 +1 for Hychill. I have an 81 SC with the standard air con setup with the exception of a 3.2 compressor, barrier hoses and a Rennaire 'pro cooler'. The AC works fine 90% of the time as long as the car hasn't been sitting in the sun on a 40 deg plus day. Hychill is much more efficient than R134 and will improve the efficiency of what is a a compromised system in the 911.Cant say whether the Rennaire pro cooler adds much-its meant to be the same as adding another condensor to the system. I think upgrading the condensors to a more modern type probably adds some extra efficiency. The deck lid condensor will does make the engine run hotter. The other options to improve the efficiency of the system is to fit a condensor in the rear wheel well-in the style of the 964. Kits are available from Griffith and ALLZIM (see http://www.allzim.com/store/911-912-parts/porsche-911-930-912e-74-89/heating-and-air-conditioning/air-conditioning-upgrades/). If i had my time again i would probably do the latter and ditch the deckled condensor. Lukas Link to comment Share on other sites More sharing options...
SimonN Posted 13October, 2017 Report Share Posted 13October, 2017 CaledonianI got everything from Autohaus Hamilton. They aren't keen on supplying the DIY market because it is never straight remove and fit the new parts as there is a load of custom brackets to make the modern bits fit. All i needed to know was that you needed to fiddle, bend, push and adjust to get everything to fit and I was fine. I did get their evaporator fan, but could easily have bought the Griffin.As for dryer and hi/lo switch, I thought of getting a single unit but ended up separating them. For me, i realised that you could fit it in the engine bay and that made wiring really easy as you simply spliced it into the existing loom with connectors. I have a thing about running wires any distance. More important than where to place it is simply placing one in the system. It will stop you destroying your compressor if you have a leak and are down on pressure or blowing the system up because you over gas it. As a DIY and tight fisted #@&^ not replacing the hoses, i thought either was a possibility! Link to comment Share on other sites More sharing options...
Caledonian Posted 13October, 2017 Author Report Share Posted 13October, 2017 https://www.flickr.com/photos/152710446@N03/shares/643LM8The compressor is now bolted, belted and aligned, turns out I had the correct belt in my stock that I forgot about. Went out for a quick drive which took the kinks out of the belt [no clutch engaged of course] now have some room for a little more adjustment as the compressor still has very little gap between the back of it and one of the inlet manifolds.All going to plan I'm hoping to get all the hoses out over the weekend.To be continued. Link to comment Share on other sites More sharing options...
Caledonian Posted 15October, 2017 Author Report Share Posted 15October, 2017 The stripping out of the A/C hoses, front condenser and evaporator is now done. And as SimonN commented previously, it's a dirty job. Although it is a fairly straightforward one, except for a couple of the hoses tharn put up a good fight due to being in the same position for nearly 40 years.https://www.flickr.com/photos/152710446@N03/shares/yi72s7 As usual with old cars when you start taking them apart you always find more stuff, this time it was the plywood footboard water damaged, probably due to the fresh air blower drain hose being cracked, actually it fell apart in my hands. This board is not curved like the driver side so should be easy to copy but the damaged hose is NLA so off to Bunnings see what I can find.https://www.flickr.com/gp/152710446@N03/sKh6tGthese out of the majority of the AC components laid out roughly as they go in car.https://www.flickr.com/photos/152710446@N03/shares/2Nt5uFHoses ready to go to get remade and drier to get matched up.https://www.flickr.com/gp/152710446@N03/1z19RpTo be continued.., Link to comment Share on other sites More sharing options...
Peter M Posted 15October, 2017 Report Share Posted 15October, 2017 Mike,Just a tip with the hoses. Take some time to make sure the ends are "clocked" in relation to each other correctly. Just makes the install easier especially with the short hoses. I'm sure you've got it covered but just in case.... Link to comment Share on other sites More sharing options...
Caledonian Posted 15October, 2017 Author Report Share Posted 15October, 2017 Mike,Just a tip with the hoses. Take some time to make sure the ends are "clocked" in relation to each other correctly. Just makes the install easier especially with the short hoses. I'm sure you've got it covered but just in case....All tips welcome Peter, best to find out before than after....The guy I'm getting to make then did warn me not to cut the hoses for that reason (would have been way easier if I could have ), which a good job as that was what I was planning to do if getting the Griffith set. Link to comment Share on other sites More sharing options...
Caledonian Posted 28October, 2017 Author Report Share Posted 28October, 2017 So after some discussion with the Auto Sparky who is doing the hoses for me, along with some of the replies posted by PFAers sharing their AC experiences, the plan has changed a little. At this point I'm going to stay with the original condensers and evaporator, upgrading only the evaporator fan motor and replacing the front condenser motor/fan assembly. This of course is subject to all of them passing the flush and pressure test, the TX valve will be replaced also.The new motors arrived from Griffith on Friday [very well packaged I have to say] and the postage ended up being 40% less than what they estimated! The front evaporator blower motor assembly Consists of a Bosch motor and they have sourced the fan from somewhere? It appears to be well made and more robust than the original but has no identifying marks. The upgraded evaporator motor funnily enough appears to have had any identifying marks [brand , Part number etc.] filed or ground off. This would suggest it is a proprietary part and Griffiths understandably don't want to give the source away. The evaporator motor also comes with detailed fitting instructions as there is some minor modifications required to fit it, the condenser blower fan is a direct replacement.https://www.flickr.com/photos/152710446@N03/shares/c28M38The new barrier hoses should be ready next week and can then start the refit, in their mean I have been fixing up some of the other little jobs that you find when you take old cars apart. Phone suitable who is to replace the crusty blower motor drain the crumbled away, Only need about 40cm but it only came in a 3m length slit anyone need some let me know.https://www.flickr.com/photos/152710446@N03/shares/5L7536I am going to replace the fuel tank sender, vapor canister hoses etc. in an attempt to combat a fuel smell after filling up?Passenger footboard is a bit past its best, so will be attempting to make a new one.Also got some Turbo tie rods to go on, which might be easier as I already have half the car apart ?⚙️To be continued...... Link to comment Share on other sites More sharing options...
Peter M Posted 29October, 2017 Report Share Posted 29October, 2017 Sorry to add to your list Mike but while you have the front condenser fan unit out I suggest you slice in a fuse in the short harness that goes between the fan motor and the main wiring harness plug. (Narva do a nice selection of in-line fuses that anyone with a pre 964 car probably need to be come familiar with). Add the unfused two dash lights circuits to your list to add fuses too if you haven't done them already!I think going with Griffith for the evaporator blower motor was a good idea. I went for the Retroair (now owned by Classicair) motor and squirrel cage combo which wasn't cheap but was disappointed how out of balance the fan was. Link to comment Share on other sites More sharing options...
Caledonian Posted 29October, 2017 Author Report Share Posted 29October, 2017 Thanks Peter, consider the fuses added but what amp do you recommend? Link to comment Share on other sites More sharing options...
Peter M Posted 29October, 2017 Report Share Posted 29October, 2017 Porsche finally recognised a problem existed and issued a TSB in 8-88 that outlined the addition of a 7.5 amp fuse to the power cable going to the condenser motor by way of an extra fused wiring harness (911.612.077.00) that goes between the two existing harnesses. This can be retrofitted to all pre 8-88 cars. I did that with my last 3.2 but found the extra wiring harness looked untidy so with my current car I just neatly spliced in a fuse holder into the original fan harness while I had the motor out for servicing.Since I couldn't find any 7.5 amp fuses I used a 10 amp.With the dash lights, I used 1.5 amp fuses. I did a bit of a write up in Jeff's (MFX) homebuilt thread earlier this year that gave some detail around the dash light circuits like wire colour etc. I can probably find it if you want. Link to comment Share on other sites More sharing options...
Caledonian Posted 30October, 2017 Author Report Share Posted 30October, 2017 Thanks Peter, I go check those posts and let know if I can't find it. Link to comment Share on other sites More sharing options...
Caledonian Posted 31October, 2017 Author Report Share Posted 31October, 2017 Gave the condensers and evaporator bit of a clean up and straightened up the fins with my $10 eBay fin comb, it did a pretty good job and helped clean out some of the muck too, now dropped off with the sparky for flush and check.https://www.flickr.com/photos/152710446@N03/shares/uS6qSPStarted the install of the new evaporator fan motor, and while the shrouds appeared to be in pretty good condition still sensed they would be quite fragile after 40 years. So after very gently scraping out the sealer I managed to separate the two parts to remove the motor, the fan is in very good condition with no marks or corrosion. The grub screw came out without a fight and a gentle tap got the fan to move on the shaft, but just to ensure it came off without any damage some lubrication was added and I will let that sit for a bit before removing the fan.https://www.flickr.com/photos/152710446@N03/shares/84nA3N To be continued...... Link to comment Share on other sites More sharing options...
Caledonian Posted 4November, 2017 Author Report Share Posted 4November, 2017 Fitted the new evaporator fan from Griffith, fairly straightforward job thanks to the detailed instructions provided. Although I do have a personal gripe regarding America's insistence on still using imperial measurements In the 21st century?Glad I got it as the old one ( which seemed to work fine] was toast! with the top bearing totally stuffed...https://www.flickr.com/gp/152710446@N03/89Wr40 Question for those of you who have been down this path before, the inner part of the fun her saying that the motor bolts to, was sealed around the edge where it fits into the outer housing with some sort of Redish brown substance? Cleaning this off (and still, more to be done) took more time than anything else! Anyone else have this and if so was did you use to re-seal it?https://www.flickr.com/photos/152710446@N03/shares/6boKYV The instructions advise using a dial indicator gauge to check and adjust any runout/wobble on the fan wheel, but I did not have one of those I went for a low tech approach. The was no tolerance/specs given in the instructions, just Pretty much the best you can get it. So so I twisted and tweaked and turned the wheel until it was as they say in the old country "within a ba hair" that would be 1 pubic hair in imperial for those not familiar with the term? https://www.flickr.com/photos/152710446@N03/shares/C8AuEM The front condenser motor\fan assembly is a pretty straightforward swap over. As you can see in the pic that's for melted motor looks like, and the reason there was a modification of an in-line fuse added (nod to Peter M). The halves of the housing where originally riveted together, and just need to get some nuts and bolts to complete the reassemble with a little sealer in the joint.https://www.flickr.com/photos/152710446@N03/shares/gD01iE to be continued… Link to comment Share on other sites More sharing options...
Peter M Posted 4November, 2017 Report Share Posted 4November, 2017 Mike,ive just used Sikaflex previously to seal the case and the inner plate. Can't remember the type number (271?) but can buy at Bunnings in a small tube as you don't need much. Link to comment Share on other sites More sharing options...
Caledonian Posted 4November, 2017 Author Report Share Posted 4November, 2017 Mike,ive just used Sikaflex previously to seal the case and the inner plate. Can't remember the type number (271?) but can buy at Bunnings in a small tube as you don't need much.Thanks Peter, I know the stuff you mean and I can use that on the condenser fan too.BTW found the 7.5amp fuses at Jaycar, got the inline fuse holder there too. Link to comment Share on other sites More sharing options...
Caledonian Posted 18November, 2017 Author Report Share Posted 18November, 2017 Time has been in short supply and still waiting for the A/C hoses etc. but still plenty jobs too be done.I got the front condenser blower fan all back together, bit of cleaning up and bolted back together (originally riveted).The motor had burnt out long ago and the fan was damaged trying to get it off the corroded motor shaft.https://www.flickr.com/photos/152710446@N03/shares/7E118M Some sealer for the joint faces and a new gasket for the floor mount, hopefully will ensure to leaks.https://www.flickr.com/photos/152710446@N03/shares/25AxYY A quick test showed no vibration and just to splice in the in line fuse and sh ishe is good to go.Hoping to get some the "while I'm in there"!jobs done tomorrow.To be continued.... Link to comment Share on other sites More sharing options...
.jpg.ad1a72e798afeef82ad7d842b8811a0f.thumb.jpg.b97b92624246035b77ff34cc70f2245b.jpg)
Recommended Posts
Archived
This topic is now archived and is closed to further replies.