The Detailed E30 R-134a Conversion Thread/DIY

[Chebyshev]

I am thinking about doing this on my '89 315iX (M20) soon and I wanted to run a few things by the crowd here to hopefully minimize mistakes.

I have a compressor on the car right now that the PO said is shot (belt is off). He also gave me a Seiko-Seiki SS-811PB3:



Will this compressor work?

I'm looking at the following parts:

Condenser: https://www.rockauto.com/en/moreinfo...13&jsn=122
Expansion Valve: https://www.rockauto.com/en/moreinfo...1913&jsn=12188
Receiver Drier: https://www.fcpeuro.com/products/bmw...hr-64538391025
Pressure Switch: https://www.autohausaz.com/pn/64538390971
O-rings and adapters: https://www.autohausaz.com/pn/10161106-559807901

Based on the chart I think I need ISO 100 PAG oil.

I don't know what to buy for an electric fan - I saw some people talking about https://www.amazon.com/gp/product/B009OBOKI4 this fan, but it says it is only ~1000 CFM, which isn't half enough according to the original post.

A lot of the parts I see seem to be good for manufacture dates through 8/89. What changed then, anyone know? I'm not sure what month mine was made...

Am I on the right track here or do I need to change anything?

[S.J.1981]

Since i had a leak in the system as well as some broken recirculation flaps and signs that the heater valve is leaking, i decided to remove the dash and the HVAC box and re-do the the whole HVAC system again.

I was researching again on the correct oil and filling capacities for the Seiko Seiki compressor and i am getting conflicting values.

When comparing to the chart listed here, some websites mention PAG 100 oil for this compressor with 200g capacity. Other websites show PAG 46 oil with 160-170g. Some include the BMW oil part number, some do not. The R134a filling capacity ranged between 900g and 1000g. It is getting a bit confusing, since even the remanufactured/rebuilt compressors for the Seiko Seiki are also conflicting between those values (PAG 100 for some, PAG 46 for others). I currently have PAG 100 in the system, but i am willing to drain and flush it again for PAG 46 if it is the correct one. I even came across some E32 posts with the same compressor, also conflicting between PAG 100 and PAG 46.

I am uncertain at this point on what to do, which oil viscosity and fill capacity? Any advice would be appreciated.

[cory58]

I am doing the r134 conversion on my 1984 318i. Can anyone assist on how to wire the new pressure switch?


Or should I keep the old setup low/high switch with old dryer?

My understanding is that the functionality of the system is the same whether you have the one or two switch set up. I kept the two switches because I could not get a solid answer on wiring the single switch. Just replace the dryer every time you open the system.

[S.J.1981]

I would appreciate your' opinion on this fan model:

SPAL KÜHLERVENTILATOR 2140M³ BLASEND D382-D350 T=63 / VA08-AP51/C-23S 12V

Link: https://www.rennsportshop.com/de-top...m-blasend.html

It is in German, but you can make out the details. It is a 382 mm diameter fan (15") so it should fit correct? i have seen users running a 16" fan on the condenser. It is a push type fan with 2,140M3 capability, 12v and 9.9amps. I have already done the conversion last year (Nissens parallel flow condenser, cleaned out the hoses, new o-rings, expansion valve and new drier/receiver) but there is a tiny leak at the expansion valve, i emptied the system getting ready for repairs.

I could also order the Spal mounts, they come in various sizes (19mm, 28.7mm, and 58.6mm), i would be keeping the factory radiator/water pump fan and electrical system, already have a lower temp. switch on the radiator as well as a lower thermostat (it gets well over 40c/100F in summer here).

[Frog]

I am doing the r134 conversion on my 1984 318i. Can anyone assist on how to wire the new pressure switch?



Or should I keep the old setup low/high switch with old dryer?

[doglegleft]

Thanks for the response! I actually took some clearer pictures and forgot to post them. Bad news that I have a Seiko. Was planning to have Jay Stratton rebuild it but he doesn't do Seikos. I've also heard good things about Polar Bear in FL, so it looks like I need to call them.

Cory

Funny you mention Polar Bear... I ordered the shaft seal kit for the Seiko Seiki SS-170 which according to Polar Bear is also compatible with the SS-811PB3, Polar Bear's part number is SS-0842.

[cory58]

You have a Seiko Seiki 6452-1386-464. The Seiko Seiki part # is SS-811PB3. I have the same compressor and am not sure if it was original with the car. I was hoping to find a re-manufactured r134a compressor as part of a proper conversion.

Did anyone source a replacement for a Seiko Seiki 6452-1386-464 that didn't require modification to the mounting bracket or fittings?

Thanks for the response! I actually took some clearer pictures and forgot to post them. Bad news that I have a Seiko. Was planning to have Jay Stratton rebuild it but he doesn't do Seikos. I've also heard good things about Polar Bear in FL, so it looks like I need to give them a call. I ordered all new hoses but now I wonder if the replacement will fit this compressor.

Cory

[doglegleft]

I apologize for the bad pictures. I need to replace or rebuild the compressor on my Touring. Does anyone know which of the E30 compressors is pictured below?

Thanks, Cory

AC Compressor 1 by cory58f5, on Flickr
AC Compressor 2 by cory58f5, on Flickr

You have a Seiko Seiki 6452-1386-464. The Seiko Seiki part # is SS-811PB3. I have the same compressor and am not sure if it was original with the car. I was hoping to find a re-manufactured r134a compressor as part of a proper conversion.

Did anyone source a replacement for a Seiko Seiki 6452-1386-464 that didn't require modification to the mounting bracket or fittings?

[mchang]

The expansion valve is NLA. FCP Euro has this one as possible cross reference. Anyone verify this works?

[ghrays]

Ok so this is how it came, just unbolt the 2 nuts on each end, pull the metal rail off, flip it and reverse it :)

This worked perfectly, thank you so much. I can't believe I never thought of taking off the whole bottom end and reversing it like that.

[doglegleft]

Ok so this is how it came, just unbolt the 2 nuts on each end, pull the metal rail off, flip it and reverse it :)

Mint, thanks.

[Albie325]

Had the exact same problem with the Nissens condenser I bought. Figured it would be easy enough to just unbolt the bottom plate, flip it and re-attach, except that one of the soft aluminum studs broke off while unscrewing the nut. Problem was I painted it black before I realized the issue so could not send it back. Ended up Flipping the bottom bracket and JB welding the plate back in place on the broken side, works fine but annoying that this seems to be a common issues with these.

[jeffnhiscars]

I had a different brand PF but still had to rework the mounts for the Spal fan I used since they are all different. It was not a big deal

[dmautz]

Sorry guys just saw this. You are 100% correct. Was on backwards so I just unbolted and flipped. I have pictures somewhere I will post. Sent from my SAMSUNG-SM-G930A using Tapatalk

Mine was on backwards too!

[Hoffbrohaus]

Ok so this is how it came, just unbolt the 2 nuts on each end, pull the metal rail off, flip it and reverse it :)