DIY sanden compressor install on a 535is

E28 technical advice asked and given! Troubleshooting, modifications and more.
demetk
Posts: 8431
Joined: Aug 09, 2007 8:58 AM
Location: CT, USA

DIY sanden compressor install on a 535is

Post by demetk »

This thread will document a DIY of a Sanden 508 compressor conversion on my 88 535is. This conversion uses a pair of simple brackets to allow the hookup of the compressor to the oem adjusting bracket.

Image

They are used in conjunction to the later oem bracket.

Compressor installation

Installing the compressor is pretty straight forward as it just hangs off the top mounting hole of the oem a/c bracket. But you will need to enlarge that hole to 3/8" so you can use a 3/8" bolt or threaded rod to support the compressor.

Image

Here you can see the how the sanden brackets are spaced out to align with the adjuster bracket. I used multiple washers to do the spacing. The sanden bracket on the right fits on the inside of the adjuster bracket and the sanden bracket on the left fits on the outside of the adjuster bracket.

Image

Image

If you reuse the long adjuster bolt make sure to make some type of spacer to fit in between the adjuster bracket.

Image

Hose Specs

There will be 3 hoses that you will need to make if you are using a new parallel flow condenser.
All fittings are o-ring Beadlock-style fittings.

Hose sizes and fittings are known by the 6, 8, 10, 12 number designations.
The chart below shows hose I.D.’s and their corresponding size number.

#6 = 5/16"
#8 = 13/32"
#10 = 1/2"
#12 = 5/8"

1. Large suction hose from the bulkhead pipe on the side of the passenger strut tower to the compressor.

Compressor fitting: #10 - 90 degree, clocked at 12 o’clock
Bulkhead pipe fitting: #10 - 45 degree, with R12 charge port, clocked at 11 o’clock.
Hose length: 24.5" #10 hose.

Image
Image

The clocking is important because it allows the fittings to be oriented to each other so that the hose does not need to be twisted in order to get the fittings connected. For example, in the above spec the 90 degree fitting end would be pointing straight up (12 o’clock). This fitting will be your reference fitting. Note it doesn't matter which fitting you choose as your reference fitting. All that matters is that your refence fitting be pointing straight up at 12 o'clock like this,

Image

Then the 45 degree fitting end would be pointing straight up and slightly to the left like this,

Image

It’s way easier just to say it’s, clocked at 11 o’clock. If you choose the 45 degree fitting as the reference fitting, then the other fitting will still come out to 11 o'clock.

2a. Compressor to condenser hose (option 1).

Compressor fitting: #8 - 135 degree, clocked at 12 o’clock
Condenser fitting: #8 - 90 degree, clocked at 12 o’clock.
Hose length: 41" #8 hose.

This option will route the hose under the car just like the original hose.

Image

2b. Compressor to condenser hose (option 2).

Compressor fitting: #8 - 90 degree, clocked at 12 o’clock
Condenser fitting: #8 - 90 degree, clocked at 12 o’clock.
Hose length: 22.5" #8 hose.

This option will route the hose along the top of the frame rail and through the opening at the rad support and then up to the top port on the condenser.

Image
Image

3a. Condenser to filter drier hose (option 1).
Condenser fitting: #6 - 90 degree, clocked at 12 o’clock
Filter drier fitting: #8 (fitting end) to #6 (hose end) - 45 degree, clocked at 3 o’clock.
Hose length: 16" #6 hose.

This hose is a #6 hose with a #6 fitting at the condenser port and a special fitting at the filter drier end that is a #6 at the hose end and a #8 at the fitting end. I couldn’t find such a fitting so I used a #6 weld on barb and braised it to a #8 fitting.

Image
Image

Alternatively you can go with option 2 where you should be able to source a #6 (fitting end) to #8 (hose end) fitting.

3b. Condenser to filter drier hose (option 2).

Condenser fitting: #6 (fitting end) to #8 (hose end) - 90 degree, clocked at 12 o’clock
Filter drier fitting: #8 - 45 degree, clocked at 3 o’clock.
Hose length: 16" #8 hose.

Given these hose specs above you can order your hoses directly from a place like ColdHose https://coldhose.com/custom-hose/custom-ac-hose.html for about $35 for each hose. That sounds like a deal.

Comments and/or lessons learned from those that have tried this retrofit and were either successful or unsuccessful are welcomed and will be invaluable to others contemplating this conversion.

Questions from those contemplating this conversion are also welcome.

Update: April 26, 2019

Here are some pics of using the larger 22x22 condenser. Using the larger condenser guarantees that enough liquid freon is available to the evaporator.

Image

Image

Image

Image

Image
Last edited by demetk on Jul 15, 2019 9:47 PM, edited 7 times in total.
camplo
Posts: 125
Joined: Dec 02, 2016 6:38 PM
Location: Bay Area

Re: DIY sanden compressor install on a 535is

Post by camplo »

THANK YOU! Going to order the hoses and pf condenser. All thats left will be the compressor, by the time I get it installed it will probably be only 6-12 months from now lol
George
Posts: 2889
Joined: Sep 12, 2007 11:23 PM
Location: Seattle, WA

Re: DIY sanden compressor install on a 535is

Post by George »

Well done.

I was always under the impression that Dash (-) numbers on a hose size were divided by 16.

-6 = 6/16 = 3/8"
-8 = 8/16 = 1/2"

Are the sizes you posed from Cold Hose specific to that company, a super secret freon sizing or am I just mistaken?
freedspeak
Posts: 487
Joined: Oct 13, 2014 10:18 AM
Location: Raleigh, NC

Re: DIY sanden compressor install on a 535is

Post by freedspeak »

it would be awesome to sticky this!
gaberdee
Posts: 415
Joined: Apr 03, 2011 6:15 PM
Location: Brooklyn, NY

Re: DIY sanden compressor install on a 535is

Post by gaberdee »

freedspeak wrote:it would be awesome to sticky this!

X2

Your efforts to make a vent temp of 36F an acheviable goal are remarkable.

I feel stupid asking, but are the hose fittings metric? The fittings on my e12 have the telltale notches, but since there are none on the e28 fittings I wanted to confirm before placing an order.

Thanks in advance,
Gabe
russellrh72
Posts: 631
Joined: Apr 14, 2016 11:52 AM
Location: Winston-Salem, NC

Re: DIY sanden compressor install on a 535is

Post by russellrh72 »

You are the man, Jim!! Your info on this forum is the reason I have A/C. Life saver for sure!! :bow:
demetk
Posts: 8431
Joined: Aug 09, 2007 8:58 AM
Location: CT, USA

Re: DIY sanden compressor install on a 535is

Post by demetk »

gaberdee wrote:I feel stupid asking, but are the hose fittings metric? The fittings on my e12 have the telltale notches, but since there are none on the e28 fittings I wanted to confirm before placing an order.
I felt the same. :) After being initially thoroughly confused, I finally realized that for the A/C systems everything is standard SAE sizes.
demetk
Posts: 8431
Joined: Aug 09, 2007 8:58 AM
Location: CT, USA

Re: DIY sanden compressor install on a 535is

Post by demetk »

russellrh72 wrote:You are the man, Jim!! Your info on this forum is the reason I have A/C. Life saver for sure!! :bow:
LOL. So you're getting 36 degrees out of the vent with the compressor jumped?
russellrh72
Posts: 631
Joined: Apr 14, 2016 11:52 AM
Location: Winston-Salem, NC

Re: DIY sanden compressor install on a 535is

Post by russellrh72 »

36.4 to be exact. Amazing. I get 37 at idle. The coldest I get out of my e60 is 42. Now I just have to figure out why I have to have it jumped. I posted about my short cycling issue and someone said it could be the control unit behind the temp dial. Looking into it....
demetk
Posts: 8431
Joined: Aug 09, 2007 8:58 AM
Location: CT, USA

Re: DIY sanden compressor install on a 535is

Post by demetk »

You may be holding the record. Not too bad with 2 cans of keyboard cleaner.
camplo
Posts: 125
Joined: Dec 02, 2016 6:38 PM
Location: Bay Area

Re: DIY sanden compressor install on a 535is

Post by camplo »

I want to go ahead and start ordering the parts, but I just want to make sure that I am understanding the hoses correctly. For the last hose as an example is this correct?
3b. Condenser to filter drier hose (option 2).

Condenser fitting: #6 (fitting end) to #8 (hose end) - 90 degree, clocked at 12 o’clock
Filter drier fitting: #8 - 45 degree, clocked at 3 o’clock.
Hose length: 16" #8 hose.
Edit: I just noticed the fittings should have the BL prefix instead of the pictured SB
Image
demetk
Posts: 8431
Joined: Aug 09, 2007 8:58 AM
Location: CT, USA

Re: DIY sanden compressor install on a 535is

Post by demetk »

I think the "L" in "BL" vs "S" in "BS" relates to the material. "S" for steel and 'L" for aluminum. It's your choice.
demetk
Posts: 8431
Joined: Aug 09, 2007 8:58 AM
Location: CT, USA

Re: DIY sanden compressor install on a 535is

Post by demetk »

3b. Condenser to filter drier hose (option 2).

Condenser fitting: #6 (fitting end) to #8 (hose end) - 90 degree, clocked at 12 o’clock
Filter drier fitting: #8 - 45 degree, clocked at 3 o’clock.
Hose length: 16" #8 hose.
This hose is a little special in that at the condenser, you need a #6 fitting end to connect to the condenser but the hose end of the fitting steps up to a #8 hose. That's because the drier needs a #8 fitting for the connection. I checked the coldhose site and I believe I saw such a step-up fitting. Like this one, https://coldhose.com/fittings/oring/fem ... g-639.html
camplo
Posts: 125
Joined: Dec 02, 2016 6:38 PM
Location: Bay Area

Re: DIY sanden compressor install on a 535is

Post by camplo »

demetk wrote:
3b. Condenser to filter drier hose (option 2).

Condenser fitting: #6 (fitting end) to #8 (hose end) - 90 degree, clocked at 12 o’clock
Filter drier fitting: #8 - 45 degree, clocked at 3 o’clock.
Hose length: 16" #8 hose.
This hose is a little special in that at the condenser, you need a #6 fitting end to connect to the condenser but the hose end of the fitting steps up to a #8 hose. That's because the drier needs a #8 fitting for the connection. I checked the coldhose site and I believe I saw such a step-up fitting. Like this one, https://coldhose.com/fittings/oring/fem ... g-639.html
Oh ok. This was the hose I was concerned about ordering. I am not as familiar with ac stuff, thanks for confirming. If it would be helpful I could screenshot the hoses I order for other.
demetk
Posts: 8431
Joined: Aug 09, 2007 8:58 AM
Location: CT, USA

Re: DIY sanden compressor install on a 535is

Post by demetk »

camplo wrote:Oh ok. This was the hose I was concerned about ordering. I am not as familiar with ac stuff, thanks for confirming. If it would be helpful I could screenshot the hoses I order for other.
I think you may be the first to order the hoses from them based on my specs. Hopefully I'm not wrong on anything but you never know. Do you want me to verify by ordering the hoses from them and test fitting on my car before ordering yourself?
camplo
Posts: 125
Joined: Dec 02, 2016 6:38 PM
Location: Bay Area

Re: DIY sanden compressor install on a 535is

Post by camplo »

demetk wrote:
camplo wrote:Oh ok. This was the hose I was concerned about ordering. I am not as familiar with ac stuff, thanks for confirming. If it would be helpful I could screenshot the hoses I order for other.
I think you may be the first to order the hoses from them based on my specs. Hopefully I'm not wrong on anything but you never know. Do you want me to verify by ordering the hoses from them and test fitting on my car before ordering yourself?
That would be amazing. I was going to order next month once things settled down a bit. I wonder if they would be willing to do a price break if we did a bulk order as well.
Jeffnhiscars
Posts: 19
Joined: Apr 30, 2016 10:04 AM
Location: Tampa, FL

Re: DIY sanden compressor install on a 535is

Post by Jeffnhiscars »

demetk wrote:I think the "L" in "BL" vs "S" in "BS" relates to the material. "S" for steel and 'L" for aluminum. It's your choice.
I went through much of this when upgrading my e30 cabrio. You do want the hose fitting to be the same metal as the connection on the compressor to avoid corrosion due to dissimilar metals. My mounting bracket was designed for a Seltec and during my compressor research I saw that some compressors have the hose connections on the end plate and are available with either an aluminum or steel end plate.
demetk
Posts: 8431
Joined: Aug 09, 2007 8:58 AM
Location: CT, USA

Re: DIY sanden compressor install on a 535is

Post by demetk »

Bought a 22"x22" condenser for the project M5.

Image

The inlet hose to the condenser runs on the other side of the rad support. You need to notch the rad support a tiny bit to get the hose to fit.

Image

cheers.
Last edited by demetk on May 28, 2019 1:04 PM, edited 3 times in total.
catso
Posts: 100
Joined: Oct 19, 2010 8:53 PM
Location: Chicago

Re: DIY sanden compressor install on a 535is

Post by catso »

Nice writeup for a well thought out modification!
vinceg101
Posts: 4802
Joined: Jun 20, 2007 2:40 AM
Location: Los Angeles, CA

Re: DIY sanden compressor install on a 535is

Post by vinceg101 »

demetk wrote:Bought a 21"x21" condenser for the project M5.
Where did you source the condenser?
I can kind of see by the photos, but what did you use to attach it to the side frames? Is that just standard L-metal (or bent flat stock)?
And the more critical question: how does it work? (I understand it's November back east)

Great write-up, thanks for doing this.
demetk
Posts: 8431
Joined: Aug 09, 2007 8:58 AM
Location: CT, USA

Re: DIY sanden compressor install on a 535is

Post by demetk »

I sourced the condenser from these guys. $52 shipped. https://www.ebay.com/itm/CNFP2121-AC-A- ... 2749.l2649

I used 1/8" flat stock but galvanized L-metal would be better. The rad support did need a small section cut out to allow the a/c fitting to run to the other side. Not sure on the performance improvement yet as it's getting cold over here but, as usual, I am going to use a sanden compressor with R152.

The aluminum rad I sourced from these guys. $130 shipped. https://www.aliexpress.com/item/HIGH-qu ... 0.0.hzZtiI. Good welds and it fit nicely with just some trimming to the two hoses. I've asked if they can build me an M5 rad and they came back with a quote of $120.

Now that the temporary turbo motor is installed in the M5, I plan on being able to drive it on good days over the winter.
demetk
Posts: 8431
Joined: Aug 09, 2007 8:58 AM
Location: CT, USA

Re: DIY sanden compressor install on a 535is

Post by demetk »

Pics updated.
catso
Posts: 100
Joined: Oct 19, 2010 8:53 PM
Location: Chicago

Re: DIY sanden compressor install on a 535is

Post by catso »

demetk wrote:Pics updated.
To reiterate: really great thread!
benloveless1
Posts: 230
Joined: Jul 08, 2015 12:14 AM
Location: Murfreesboro, TN

Re: DIY sanden compressor install on a 535is

Post by benloveless1 »

I would like to place an order for these hoses. Has anyone else done this besides OP? Are the dimensions correct? Also what size condenser was used for the hoses ordered?
demetk
Posts: 8431
Joined: Aug 09, 2007 8:58 AM
Location: CT, USA

Re: DIY sanden compressor install on a 535is

Post by demetk »

The hose specs above are for the 18" wide x 16" high condenser that has a #8 inlet port and a #6 outlet port.

Note that because the compressor on the M5 will need to be clocked at 90 degrees the hose lengths and clocking angles of the fittings will change.

If you're hesitant on ordering made up hoses from the specs above, I would suggest you buy the fittings and hoses separately, cut the hoses to length and loose fit the fittings in place. Once you're satisfied with the fit, mark the fittings to the hoses and have them crimped at a local a/c shop.
Post Reply