R134a conversion for 325iX

[richardodn]

I've decided to do a R134a conversion on my 1989 325iX. I debated with myself between fixing the current R12 system and doing the conversion. As I intend on keeping it for some time to come, I've opted for the conversion. The current system likely has a leak in it somewhere. The compressor clutch won't kick in unless I jump the low pressure switch which leads me to believe that the R12 is gone. In any event, I figured if I'm going to do this I will do it the "right" way.

compressor - I'm going with a remanufactured Behr-Bosch unit compatible with R134a. I basically have 3 OE choices; the Behr-Bosch, the Seiko-Seiki SS-148DW7, or the Denso 10P15E. The SS unit does not have an available suction hose for the iX with the required #10 fitting. (There is one for the 325i.) If I have my facts straight, the Denso unit requires a different pressure hose which is not generally available. Finally, I'll be able to use my existing compressor for any core charge. Just to be sure, I believe I need the unit that is 4 Seasons PN 57400. Also, has anyone dealt with this Ebay vendor, Bloomfield Compressor (http://stores.ebay.com/bloomfieldcompressor)? I can get a remanufactured compressor for under $200 with 12 month warranty. Their auction descriptions sound like they do a thorough job.

condenser - Should I replace the condenser assuming the existing one is in good shape? Are there benefits to using the latest 64538391509 condenser?

dryer and pressure switches - Update to single switch unit.

expansion valve - Update to R134a unit.

evaporator - Should I replace the evaporator assuming the existing one is in good shape? Are there benefits to using the latest 64511468560 evaporator?

hoses - replace the 3 soft lines with R12/R134a compatible lines.

o-rings - I've gone this far. I'll replace them all with HNBR.

high & low pressure valves - convert to R134a with OE adapters.

Initial estimates are around $700 in parts including the condenser and evaporator assuming I can get a compressor for $200. Special thanks to DJB2 for all his informative AC posts. Any comments, suggestions, or answers to questions? Thanks.

[Dub-Dub]

Pics of work and part list/vendors would be a big win on this thread.

[nick325xit 5spd]

I'd try replacing all the seals in your R12 system. If you want A/C that actually works, you want R12. The E30 condenser isn't nearly big enough to be truly efficient with 134a.

[richardodn]

Pics of work and part list/vendors would be a big win on this thread.

Here's my parts list from a couple of vendors. Anything that I must buy OE can easily be had for 20% off list.

Description.................................BMW PN.......OE List....AAZ....Pelican
Compressor, Behr-Bosch......................64528391152..$614.41..$ 355.06..$489.00
Condensor...................................645383 91509..$452.37..$135.37..$135.25
Dryer.......................................645383 91025..$220.07...$18.95...$20.00
Pressure Switch.............................64538390971...$ 75.75...$39.20...$41.25
Conversion Plug Terminal....................61131378400....$1.45.. ...........$1.50
Evaporator..................................645114 68560..$317.75..$110.49..$139.95
Expansion Valve.............................64518391209..$12 9.27............$26.00
03 PRESSURE HOSE ASSY COMPRESSOR-CONDENSER..64538391052..$102.85...$32.28...$34.00
04 CONDENSER-DRYER PRESSURE HOSE ASSY.......64538391041..$102.85...$24.27...$24.75
08 SUCTION PIPE EVAPORATOR-COMPRESSOR.......64539067571...$98.77
Valve Adapter - low.........................64509177579...$11.52
Valve Adapter - high........................64509177577...$11.52



I'd try replacing all the seals in your R12 system. If you want A/C that actually works, you want R12. The E30 condenser isn't nearly big enough to be truly efficient with 134a.
That is one of the things I'm curious about. The condenser and evaporator have both gone through many revisions. I'd like to know if the latest versions are better optimized for R134a.

[CDBE30]

Holy crap, this thread is coming at a very opportune time. I don't have much input here, but if you do go through with a full R134 conversion, a good write up would be amazing to have for my inevitable conversion.

[richardodn]

At this point I think I have everything figured out except condenser and evaporator. I'll change those out if it will improve the system but there is also no sense in just pissing money away. I've started writing a general A/C parts document but that has some work to go.

[nick325xit 5spd]

I put a brand new condenser in my car and it's indistinguishable from the older ones aside from being pretty and new. You want a double row condenser that's a lot thicker, and I can assure you that any revision won't be significantly changed.

[richardodn]

Well that certainly puts a damper on my thinking. Any input on the effectiveness of the R134a expansion valve in an R12 system? I'm still inclined on doing a rebuild on the whole system so that it is R134a ready even if I stay with R12 for now. Also, is there a quick way to figure out if there is any R12 left in the system. I'd like to know if I need to have the system purged before beginning work on it.

[nick325xit 5spd]

Well that certainly puts a damper on my thinking. Any input on the effectiveness of the R134a expansion valve in an R12 system? I'm still inclined on doing a rebuild on the whole system so that it is R134a ready even if I stay with R12 for now. Also, is there a quick way to figure out if there is any R12 left in the system. I'd like to know if I need to have the system purged before beginning work on it.
It's not really possible to tell unless you put a manifold gauge on it.. Many a/c places will buy any R12 that's left, though.

I have an R134a system, and it performs, well, acceptably. Ish. With the aux fan resistor bypassed (so that the fan runs full speed all the time), it's fine. It's nothing like the R12 system in my girlfriend's iX, though.

R12 expansion valves are no longer available, so you can use your R134a one.
See here: http://www.e30tech.com/forum/showpost.php?p=1051662&postcount=9
The whole post is also informative, and there's a LOT of information in the HVAC forum there.

[garretvs]

I'd try replacing all the seals in your R12 system. If you want A/C that actually works, you want R12. The E30 condenser isn't nearly big enough to be truly efficient with 134a.

We have an R134a system in our car. We put in new condenser, evaporator, expansion valve and receiver-drier -- all standard E30 parts. The compressor is a Sanden unit as found on the LS1 engine. It blows Really Cold. Don't worry about the horror stories regarding R12/R134 cooling capacity. The BMW E30 condenser and evaporator are more than adequate. It is a little tricky getting the "Freeze-Up" probe back into the evaporator.

[nick325xit 5spd]

We have an R134a system in our car. We put in new condenser, evaporator, expansion valve and receiver-drier -- all standard E30 parts. The compressor is a Sanden unit as found on the LS1 engine. It blows Really Cold. Don't worry about the horror stories regarding R12/R134 cooling capacity. The BMW E30 condenser and evaporator are more than adequate. It is a little tricky getting the "Freeze-Up" probe back into the evaporator.
Are you seriously claiming that he should spend 2-5 times as much to retrofit R134a as it would cost him to replace the seals, switches, expansion valve, and recharge with R12?

I have never been in an R134a E30 that blows REALLY COLD, so I'll have to take your word for it. Mine is adequate, but nothing special. I'm not one of those guys who claim that R134a doesn't work, I just don't see how you can even claim that it works as well as R12 (it doesn't), and I don't see how it makes sense to spend much more money to get a system that doesn't work as well.

[richardodn]

Guys, don't start a R12 vs R134a flame war going. There's been enough of those already.

@nick325xit5spd - Thanks for pointing me over to that forum. I've got a bit of reading and digesting to do before I determine what is best for my situation.

[UKFan4Sure!]

Guys, don't start a R12 vs R134a flame war going. There's been enough of those already.

@nick325xit5spd - Thanks for pointing me over to that forum. I've got a bit of reading and digesting to do before I determine what is best for my situation.

I agree on the flaming. Thanks for nipping that in the bud. Have you considered this, though? This might be a cheaper alternative to what anyone has suggested, although I must admit I haven't used it:

http://www.duracool.com/Duracool/refrigerants.html

[richardodn]

I thought about alternate refrigerants. However my goal is a functioning stock system that is serviceable and really that means R134a. I'm not necessarily looking for the cheapest way. I just want to spend my money sensibly.

[Fleksta]

I just used the BavAuto conversion kit. Came with the dryer, new fill ports, o-rings, and instructions for converting to a single pressure switch. Had a garage purge and fill the system, now I have A/C :)

It doesn't blow very cold, but its much better than having none at all. They think my expansion valve is stuck having not been used for so long; so it might even get colder when I have that replaced.

[richardodn]

More info on my research. Here is where my plan sits.

compressor - Still would like to know if anyone has dealt with ebay vendor Bloomfield Compressor.

condenser - Should I replace the condenser assuming the existing one is in good shape? Are there benefits to using the latest 64538391509 condenser? According to posts so far, there are no appreciable differences between the OE parts. The existing one should work however it is not optimal. I have been researching alternate condensers in the hope of finding one more suitable for R134a. At this point I'm waiting to hear from a manufacturer called American Condensers (http://www.americancondenser.com/). They list a part (P34640P) for the E30 with parallel flow instead of the serpentine flow that the OE part has. This would probably be better for a R134a system. Any vendor listing I have seen so far that carries that brand lists a P34640S serpentine flow condenser. I'm trying to find out if the part actually exists and where it can be purchased.

dryer and pressure switches - Update to single switch unit. No change.

expansion valve - Update to R134a unit. No change.

evaporator - Should I replace the evaporator assuming the existing one is in good shape? Are there benefits to using the latest 64511468560 evaporator? Will probably just have this one flushed and cleaned.

hoses - replace the 3 soft lines with R12/R134a compatible lines. According to this post (http://www.e30tech.com/forum/showthread.php?p=611734) (excellent thread BTW) on E30Tech, cars with build dates of 9/87 have the barrier hoses already. I wont need to change them unless there is a leak in one.

o-rings - I've gone this far. I'll replace them all with HNBR. No change.

high & low pressure valves - convert to R134a with OE adapters. No change.

This brings my parts cost to under $500 assuming a compressor for under $200 and parallel flow condenser for under $150. If that part doesn't exist, I'll just have it cleaned and flushed. I'll be looking at under $350 then.

[UKFan4Sure!]

.....Still would like to know if anyone has dealt with ebay vendor Bloomfield Compressor.


I haven't any experience with them, but 2700 people look pretty happy based on their feedback.

[richardodn]

I saw that too. 100% positive feedback. Not an easy thing to achieve.

[E36 For Life]

I'm not here to get into a pissing contest, but the information on the barrier hoses is in correct. I just bought one for my 89 vert and it cost me $253 at the dealer. It's the only one that will not leak r134a. Here is the part # 64-53-8-391-051. Sorry for the bad news, but one plus it that it comes with the r134a acme fitting?

[richardodn]

The hose you describe is the evaporator-compressor hose. The iX uses a different hose for that. The shock tower is in a different position. BTW if you spent $253 for that hose, you got spanked. List is $225 and places like bmwautopartsdealer.com have it for $180 + shipping.

Now if my research is right, for the normal 325e/i/iC there was the R12 hose (PN 64531377821) for connecting to the Bosch (and maybe Denso) compressor with the #12 inlet. It has the R12 valve. Then you bought the R134a hose (PN 64538391051) with the R134a valve and a #10 inlet for the Seiko-Seiki compressor. Once again according to my research, the '821 hose should have used barrier hose from 9/87 on even though it was valved for R12. How do you know it doesn't? I'd like to correct my information if I'm wrong.

As for my iX, it uses a R12/R134a hose (PN 64539067571) which implies that it is valved for R12 but uses barrier hose. This hose only lists at $100. Yours was so much more because it was never used in production. It was a part specified for retrofitting the Seiko-Seiki.

The other soft lines are all rated for R12/R134a from at least 9/87 in the ETK.

[E36 For Life]

The only way the 821 hose is barrier, is if your using the ozone as your barrier. I orderd that hose first and found no barrier hose on it any where, just swiss cheese r12 rubber, that's why I went with the 051. I did say it was for a vert and not the ix, but you are correct with the 571 (I paid $94 for that) hose for the ix and that is a barrier hose for sure(ask me how I know). I have it on my car with a bosch compressor. I changed it a year ago and have not had a leak since. All the other hoses are barrier on the car, high-side and even the hoses in the dash. The 571 does come with the r12 service port.

Here are some pictures of the 051 for your enjoyment. If you would like to see some pictures of the 571 on the ix just let me know. Sorry the only thing older than me is my camera so it sucks.

http://i652.photobucket.com/albums/uu250/gwix/DSC04619.jpg

http://i652.photobucket.com/albums/uu250/gwix/DSC04620.jpg

http://i652.photobucket.com/albums/uu250/gwix/DSC04621.jpg

[aze30325softtop]

Just curious, have you looked at the side of the compressor, mine said r134a and it is a stock comp on a 1987 325i. It might save you some bucks.

Recommend whatever you do, replace all the soft lines, mine blew out after a week of use when fixed, mechanic gave me the freon as he said the lines would hold, very nice of him.

[richardodn]

OK this is starting to make some sense. Am I correct that the way to tell if it's barrier hose is the spiral wrapping around the tube? If so, the evaporator-compressor hose ('571) is a barrier hose. However mine is missing a heat shield. Does the one on your iX have it? The compressor-condenser hose is not barrier hose. All the remaining are barrier hoses. So there is one I must replace and one I should replace. Now the non-barrier hose may not be an OE hose. That area always looked like it had been messed with.

[E36 For Life]

The spiral wrapping is nylon which is a good indicator, but the inside also has to have the nylon as well. Another quick way to tell is by the crimping, on r134a hoses they will use a bubble crimp (just like in the picture above). If you have both those present there is no doubt you have a barrier hose.

Yeah, the 571 barrier hose I bought for my ix didn't have the heat shield on either and it has the r12 service port.

The compressor-condenser hose you have must have been changed. I quess in my statement eariler I should have said "if the high-side hoses are all oe" they will be barrier.That has to be a high pressure hose and that should have the nylon on the inside, but I would change it just to be safe.

[richardodn]

I looked again this morning. The non-barrier hose is definitely not original BMW. Was the iX a R134a conversion? If so, what did you do about the valve port fitting by the hood hinge? It looks pretty tight to put an adapter on.

Also, was I correct that the cabrio has the Seiko-Seiki compressor?

[E36 For Life]

As a side note the only things I changed on my stock r12 car were the 571 hose, removed the mineral oil and replaced it with ester oil. The ester is less toxic when mixed with the r134a than pag and does a good job. My car is not a snow blower, but in the Florida heat it will get down to the low 60's at high noon.

Yes the ix was a r134a converson.

The high side port fits on there. It is close the first time you close the hood, close it slow to maks sure it doesn't hit, if it does just bend the hing in a little.

No the cabrio has a bosch also?

I will take some pictures (with my crappy camera) and post them up for ya later.

[richardodn]

Questions on the cabrio. The original 821 evaporator-compressor hose (R12) was specified for the Bosch compressor. From what I have read so far, the Bosch has a #12 inlet. BMW specified a Seiko-Seiki compressor for the "official" R134a conversion. Part of that conversion required the 051 hose. Now we know that the 051 is a barrier hose while the 821 is not. However from what I have read so far, the SS also had a different size (#10) connector which implies that the 051 also has a different size from the Bosch. Since I have not seen a SS compressor in the wild, I can't confirm that but it does raise some questions.

[nick325xit 5spd]

The Seiko Seiki compressor ABSOLUTELY has different fittings from the original Bosch/Denso compressors.

[richardodn]

The Seiko Seiki compressor ABSOLUTELY has different fittings from the original Bosch/Denso compressors.
Is it true that the Bosch and SS have the same general appearance? Is the difference in fittings simply the suction line diameter or are there other significant differences?

[nick325xit 5spd]

Is it true that the Bosch and SS have the same general appearance? Is the difference in fittings simply the suction line diameter or are there other significant differences?
I don't have any Bosches, but the Denso and Seiko Seiki compressors that I have are primarily differentiated by the big green R134a warning stickers on the Seikos. I've never cared enough to look for any greater level of differentiation, though.

[E36 For Life]

Here are the pictures of the Bosch and Denso,hope this helps. I don't have a Seiko to take any pictures of?

http://i652.photobucket.com/albums/uu250/gwix/DSC04622.jpg

http://i652.photobucket.com/albums/uu250/gwix/DSC04623.jpg

http://i652.photobucket.com/albums/uu250/gwix/DSC04624.jpg

http://i652.photobucket.com/albums/uu250/gwix/DSC04625.jpg

http://i652.photobucket.com/albums/uu250/gwix/DSC04626.jpg

http://i652.photobucket.com/albums/uu250/gwix/DSC04628.jpg

http://i652.photobucket.com/albums/uu250/gwix/DSC04629.jpg

http://i652.photobucket.com/albums/uu250/gwix/DSC04631.jpg

http://i652.photobucket.com/albums/uu250/gwix/DSC04630.jpg

[UKFan4Sure!]

Dang, guys.

A bit of work on refurbing he R12 system, a few cans of bootleg R12 and you're good to go.

To hell with all of this "figuring out". The R134 isn't as cool anyhow.

Anyhow, Richard.....good luck.

[richardodn]

Just a follow up to my post about the American Condensers P34640P parallel flow condenser. I don't think it really exists. The rep in the sales department was hard to get a hold of and never really answered my questions. So I gave up.