Air conditioning overhaul

[notporgu]

Not sure if this is the right place for a post like this, but here goes.

My 88 convertible 325i hasn't had AC since I bought the car, and I'm looking to finally get it working again. I want to completely replace everything, since I removed the condenser about a year ago, since it was loose and vibrating against the radiator and poking holes in them. (It killed 2 radiators before I found the issue ugh).

Anyway, the system has been open to the air for about a year, and I'm sure all kinds of nasty stuff has contaminated the lines, and the compressor, so I just want to completely overhaul the whole thing.

My first attempt at researching parts to source was promising, rockauto sells a good bit of parts that I would need, including most of the flexible ac lines, condenser, evaporator, and even a compressor kit, all at a total cost of about $500. It seemed too good to be true, so I started researching four seasons (the brand selling the compressor) on here and found that their compressors are no good. Which I guess is to be expected, who woulda thought you could get an ac compressor for a 30 year old car for only $180.

After further research (1 google search) I found this website, which sells a whole kit, replacing almost everything I was going to replace, save for the evaporator and all o-rings. However it's more than twice what I was going to spend, and currently is a little out of my budget.

Which leads me to my issue. I'm considering simply buying the compressor, mounting hardware, and interior AC lines (not sold anywhere else that I can find), and buying the rest from rock auto. That would save me probably $3-400, if not more, but I would be risking getting crappy AC lines from four seasons, and also not having the lines match up with the compressor, and I don't believe it has OEM hole locations.

Has anyone else done an AC overhaul this in depth, and if so, where did you source your parts? And about how much was it? Is that kit worth spending the extra to make sure it all fits correctly? I would still have to buy a few other things, and my total would be about $1400.


Or should I just suffer through this summer and save money to get it done by next summer?

[varg]

Do you have a local hydraulic shop or AC shop that makes lines? There may be no reason for you to replace any of the lines at all if you get a stock compressor and condenser. My local hydraulic shop will crimp new hoses on my old AC lines and their prices are reasonable. It's trivial to flush lines once they're removed from the car. Otherwise the kits that use a newer style compressor are probably a good bet.

[notporgu]

I live in a small town in north Georgia, so I'm not sure there would be any hydraulic specialists nearby. I could probably flush the lines myself, and I might do that with the hardlines (assuming I can get them out without damaging them), but considering I really don't know their age or compatibility with R134A, I really think it would be best to replace the flexible lines. And I have no idea if my compressor is good or not, I had a shop diag it when I bought the car 3 years ago, and all they told me was that it was bad. I'd prefer to just go new if at all possible. If the kit I linked is a good one, I'll probably just go with that for next summer.

[e30davie]

If I was doing the job in USA I would do the following -

buy one of these as well as a brand new sanden compressor to suit. i made my own braket here in australia, and used an SD5h09 compressor. its tiny and very light compared to OEM.

https://lcwylieco.bigcartel.com/product/m-20-bmw-sanden-conversion-bracket

Then from there all you need to do is -

- replace tx valve with r134 one (Get a new one even if you have one - they are cheap and painful to repalce, so you only want to do it once...)
- replace dryer - also cheap
- replace all the o-rings in the entire system with r134a compatible. cheap as - like $10 for all of them. but fidly
- make new hoses to suit. I made my own hoses using a hand crimp kit. they have to exist in usa too somewhere. or get a hydraulic shop to make them. its not rocket science, im sure you can find someone to make them, even if they have to do it remotely.

Making my own hoses cost me like 200bucks. This is the supplier I used, but its in Australia, but there has to be something similar local to you.

https://speedyairspares.com.au/product-category/self-crimp-sas-hose-fitting-system-build-your-own-hoses/

I had to braze a fitting onto the oem hose, local shop did it for cheap.

Connect it all up. Then get it vacuum tested. this will tell you if your condenser and evaporator is good to use. If it passes the vacuum test, fill it with gas and off you go. If it doesn't pass, find leak, fix as necessary. nothing wrong with re-using good condition evaporator and condensor. I reused the R12 condenser and evaporator, work fine on r134a. yes the r134a are "better" but honestly, its bloody hot where live and the AC is great.

[notporgu]

Thanks for all of that, I'll definitely do more research into it tomorrow. Though I do have a few questions before I go off to bed.

First, about the compressor you recommended. Is there anything I need to do to get the correct pulley? I searched the part number listed and saw a few variations on the pulley design, and wasn't sure if there was a specific type I needed, or if I can just take the one off my compressor. Also, was the fitting locations/sizes something you had to customize the hoses for? I suspect oem hoses wouldn't correctly line up with the fittings on the new compressor, and would also be different diameters.

Which leads me to my second question, is custom crimping hoses really that easy? It seems like something that high pressure would need to be done with machinery not available to the average person, but I'm seeing parts online that use simple hose clamps. IDK seems sketchy to me, but if it really is cheaper and effective to go that route, I might. I also saw in that link you sent with the bracket, that the guy will do hose work for you for like $50-$200 depending on what you select. I might reach out to him and see what the cost would be for me to send all of my hoses.

Thirdly, I've seen a few listings that show two TX valves for sale, but I can't tell for sure how many are actually needed. It's just one, correct? And would the four seasons valve on rock auto work? It's the only one that clearly lists that it's for 134a, but idk about their quality.

Lastly, and this isn't really a question, but my condenser is 100% busted. I had to bend the fitting locations just to get it out, and a Nissans parallel flow condenser is only like $100 on rock auto so it seems worth it. As for the evaporator, I want to rip out my old one anyway, at the very least to clean it, since I'll be in there for the o-rings and glove box lines anyway.

[Tzantushka]

Hello,
If you haven't already - worth having a read of this thread.

https://www.r3vlimited.com/board/forum/e30-technical-forums/e30-faq-and-diy/213651-the-detailed-e30-r-134a-conversion-thread-diy

Some of the data may be a little out of date.
But to get the system running on R134a it's not that expensive - if you plan your work it's just time consuming organising waiting for parts.

[e30davie]

I just found some photos for you I put in in here,

https://www.r3vlimited.com/board/forum/e30-technical-forums/engine-drivetrain/forced-induction/10088883-thoughts-on-ac-for-m20-turbo-project-keep-upgrade-or-ditch

Yes the compressor comes with either a V belt (mine has 2 belt pulleys in one). and there is one for the more "modern" ribbed belt. You can see in the photos that i used the most forward v belt pulley, and it only just fits with the crank sensor. I think i mention in the above thread i made a mate of mine one, for his car and i placed the compressor lower for more clearance. I am not sure exactly which sanden the LC wylie co bracket suits. but its a sanden something. edit: Just saw they offer a complete kit, that's not a bad deal really, hard to beat if its a bolt on affair.

https://lcwylieco.bigcartel.com/product/e30kit

I dont know the rock auto references, but there is only 1 TX valve. but it has 4 pipes attached to it.

https://www.bimmerworld.com/BMW-Interior/BMW-AC-Evaporators-Lines/BMW-Expansion-Valve-64518391209.html

looks like the above. pain in the ass to install on RHD car, hopefully easier on LHD.

and yes the crimping of the lines really was that easy. The crimp tool they supplied me was about 40bucks. I cant find a photo but it wasn't that special. you can see in the fittings in the above link, they have 2 rubber orings on the fitting itself, then you put the pipe over and you put 2 crimps on, which you can see in my the photos in the link. honestly it took like 20mins to do all of them and they have been working fine for years. But you have to get a fitting welded/brazed onto the OEM lines as bmw use some obscure connection. I was going to get lines made up but i'm a tight ass so went the DIY route, that has worked out well.

The low pressure side is one size of pipe/fittings, and the high pressure side is another size. I cant remember which was which but you match it to fittings on the compressor.

Its high pressure but it isn't that high. ~300psi is up there, but its not thousands of PSI like hydraulics.

couple of other photos below. The photo of the compressor on the bench, you can see the OEM bmw hardline from the dryer, that I had a generic AC fitting welded onto. I did on the same on the hose that wraps around the strut tower.

There's plenty of ways to skin a cat as they say. but this is the way I did it.

its up to you but i would not at all bother with the OEM compressor. they are so big and chunky. I tried for ages to find someone to rebuild mine, or even buy rebuild parts, just too old to find anything. Specialist companies seem to be able to do it, but it costs a bit, and you are sitll stuck with an old heavy compressor. Swap to one of these sandens, they are like 200bucks usd brand new, maybe even less. then if it ever breaks you can swap in a new one and keep going.

[ZeKahr]

The Sanden kit is totally worth it IMO if you are going to overhaul your AC. I have a white sedan with a beige interior and a functioning stock AC system running R134a and 40% tint all around, and it does start struggling once the temps get into the 90s (but works great below the 90s). The stock system was designed for R12 and won’t cool anywhere near as well with R134a.

If your vert has a beige interior, you can probably get away with no AC during this summer; just drive with the top down and let the wind be your refrigerant. Just don’t get stuck in city traffic. Now if you have a black interior, that’s a different story lol.

I drove a black sedan with a beige interior without AC last summer (I live in central NJ, our summers are slightly less bad than yours) and it was bearable. Had both windows all the way down. I want to try repeating this with my white sedan this summer and see how much more comfortable it feels (white paint gets nowhere near as hot as black paint in the sun)

[notporgu]

Thanks everyone for the additional support, I'll have to read through it all more thoroughly after I get home from work today.

Luckily I work at a tire shop, and after asking around, I have a lead on someone who can do my ac lines for me, I just need to follow up later and see what the cost will be. If the price is good, I might go that route and get everything separately.

As for my interior, it's all black unfortunately, and I really live too close to everything to bother with the top so I only save that for trips longer than 10 minutes. Also doesn't help in the rain either lol.

My current plan is to essentially rip out everything AC that's still in the car for cleaning and replacing, and I'll update here when I get a quote on the lines. If it's a good quote (should be, I might get a discount if I go through my job), I'll buy the compressor and parts separately, then work with the place to redo the lines. If it's like 3-400 to do all 5 lines, I'll just save for the kit since that's about what it would cost anyway.

[cory58]

Another happy LC Wylie customer here. Lane was great to work with. His conversion bracket is well engineered and made. He can sell you modified soft lines with updated hose and fittings for the compressor. He can also help you buy the correct Sanden compressor and correct belt.

[notporgu]

Another happy LC Wylie customer here. Lane was great to work with. His conversion bracket is well engineered and made. He can sell you modified soft lines with updated hose and fittings for the compressor. He can also help you buy the correct Sanden compressor and correct belt.

I'm really debating if it's worth the savings to try and do it locally, especially when there's a kit ready made for this.

When he remakes the hoses, does he do that all new or is there a core system?

[notporgu]

Just called and asked the shop if they can do ac lines and they said no, which I guess means back to square one with getting a kit. I'll reach out to LC Wylie to see what their options are with supplying the lines to be redone. If all else fails I'll just get the kit after I save for a bit.

[ghrays]

I spent almost two years getting my ac to work. I replaced everything, including new evaporator, condenser, lines, electric cooling fan, etc. I had my original Denso compressor rebuilt, it leaked. I bought another rebuilt compressor on eBay, it leaked. I never had AC that would work for more than a few days.

it wasn’t until I bought a brand new Sanden compressor (with Layne’s adapter bracket) and had new fittings attached to my new BMW hoses by Layne that I finally had a working AC system that did not leak refrigerant. Dealing with 30+ year-old compressors is a waste of time and money. If I had to do it all over again, I would just buy Laynes complete kit and put it on and be done with it.

finally, I do not recommend the BMW branded receiver/drier. It is nearly $250 and you can get one made by the same company for $20-$30.

[cory58]

I'm really debating if it's worth the savings to try and do it locally, especially when there's a kit ready made for this.

When he remakes the hoses, does he do that all new or is there a core system?

I bought new lines from BMW and sent them to him for modification. At the time (last year), he had a supply of modified used lines for sale. Don't think he was requiring a core.

[m2d2]

+1 L.C. Wylie kit. He is very helpful and answered all of my questions. Yes, you can save money piecing the kit together yourself, but it's the custom made lines that will be an issue tracking down. The kit is worth the price and saves a lot of headache.

My only recommendation would be to also replace the evaporator. I was able to re-use my existing dual pressure sensor setup (early model), but I do have a new plug for converting if I need to. Make sure you do the R12 to R134a capacity conversion as well. I originally overfilled to ~ 1.89lbs, which was too high and caused the system to not work correctly. I had a shop do a proper evac and fill and I think I recall them telling me it was about 1.55lbs of R134a to fill the system. It works fantastic now and definitely worth it.

Happy to answer any questions you have about an R134a conversion on a convertible.

Good luck!