Labor of love from Australia - Malachtgrun convertible running restoration

[D.Martijn]

Great thread, enjoyed reading everything you've done as of now!
Perfect color combo as well! :)

[Tzantushka]

Great thread, enjoyed reading everything you've done as of now!
Perfect color combo as well! :)

Thanks - also keeping an eye on your great progress as well.


Well I'm pleased to say that the cooling system is like new again.
The man leak was coming from the throttle body gasket and hoses.
BMW blue coolant filled and bled as per instructions here worked a treat.

While fitting everything back - noticed the foglights weren't working.
Thanks to the collective wisdom here traced it down to the switch.

After a good clean and some conductive grease it's as good as new.









Full how to clean your foglight switch here...

[Tzantushka]

Been rather quiet with the E30 since we've recently emerged from lockdown 2.0 in Melbourne.
The cooling system has been working like a champ.
Lots of heat, a quiet blower and the temp needle never goes past half-way - even in traffic.

Went to give the A/C it's normal weekly run, but no cold air.
The system worked, but was never great as it was 'converted' to R134a.

Well, found out why:



Front seal on the Bosch Behr compressor had sh*t its self.
After asking around 5-6 A/C workshops here, very few want to touch this older stuff - and virtually no one wants to rebuild these compressors.
So looks like I'll have to do a full R134a conversion:
- new barrier hoses & o-rings.
- receiver drier
- parallel flow condenser
- new expansion valve
- system flush out
- and most likely a Sanden 134a compressor.

So here's the progress so far.

Most of the front end had to be removed to get rid of the old condenser.



Ended up ordering from RockAuto in the USA - the APDI 7013464 parallel flow unit.
Different to the picture (aluminium) but definitely parallel flow and OE drop-in.

Refurbished the stock fan - stripped off the flaking paint, etch primer, epoxy black reconditioned the fan motor.



New barrier hoses made locally.


Reassembled prior to bumper & grille.


The hardest part was removing the expansion (TX) valve.
Absolute bitch on RHD without removing the dashboard & steering column to gain access to the heater + A/C unit.

After flushing the evaporator, the amount of junk that came out was unbelievable.
From the solvent recovery bucket.



Next step, re-fit the new R134a specific TX valve, refit internal barrier hoses and start on the compressor mounting bracket.
Took the expensive but well engineered route and ordered a LC Wylie M20 Sanden bracket.
It's a very good piece of kit and saves me the heart ache of fabricating something up.

The quest for cold air before summer continues.

[PieterVN]

What a lovely car! That colour is on my wish list goes perfect with the nature upholstery.

Nice job fixing the AC, my car came it, but at the moment i do not use it. It's on my list of to do's. I'll be following this conversion. Could come in handy for future use .

[Tzantushka]

What a lovely car! That colour is on my wish list goes perfect with the nature upholstery.

Nice job fixing the AC, my car came it, but at the moment i do not use it. It's on my list of to do's. I'll be following this conversion. Could come in handy for future use .

Thanks - Still a few more steps to go before I have cold air again...

[Tzantushka]

Which reminds me...
Progress update this week installing the A/C bracket and compressor after work.

In our last episode:
Took the expensive but well engineered route and ordered a LC Wylie M20 Sanden bracket.

Nice piece of kit - comes with the necessary hardware to bolt-up to the existing alloy bracket.
Saves the hassle of fabricating something up.
Don't mind helping a BMW brother who has done all the hard work.



Removed the Bosch - Behr compressor, cleaned up the area, re-sheathed the oil sensor...




Very snug fit on the alloy bracket - a 'love tap' with a soft faced hammer was needed.



Bolted up ready to some compressor action.




Which reminds me - ended up getting a Sanden SD5 compressor SD5H14 (S6626 model variant).



You need a modified low pressure line.
Ended up buying a new low pressure line than trying to resurrect the existing version.
Used a Four Seasons hose from RockAuto, cut off the end - which is for the Bosch Behr unit - and fitting a new hose connector.
The high pressure line looks OK - will report back on that later.

[burkey001]

the aircon work is very interesting. Can you tell more about the Sanden compressor?
I take it it's not an E30 part? What's it from? Is it new?
I need a R134 compressor too... very interested to learn more

thanks 🙏🙏

[Tzantushka]

the aircon work is very interesting. Can you tell more about the Sanden compressor?
I take it it's not an E30 part? What's it from? Is it new?
I need a R134 compressor too... very interested to learn more

Sure.
I spent a fair bit of time trawling through all the different options and opinions.
Like any car-related topic on the internet, there is plenty of conflicting information.

Sanden compressor
Correct, the one you see in the picture it's not an original part on my car.

It's a genuine Sanden Singapore unit, not the 'Sanden style' Chinese copies

This is a widely accepted 'universal' replacement to the Bosch Behr vane style compressor.
- R134a compatible = improved performance to the Bosch unit
- swash plate or wobble plate = lower HP draw & quieter, better efficiency at the higher pressures of 134a
- new vs risks with a rebuilt compressor
- available locally in AUS through the trade (e.g. Cooldrive) & resellers (Repco, Bursons, SCA, eBay)

Obviously requires a new bracket and changes to the fittings on the hoses.

[Tzantushka]

While I waiting for the compressor fittings and hoses to arrive, I gave the door cards and rubbers a refresh.

My existing door cards were pretty tired, warped and the vinyl was torn in a few places.
Plus the handles, door pocket and trim didn't match.

Found a set of door cards that were in great shape - the vinyl was nice.
But the back of the door cards were a different story, cracks and the holes for the door clips were blown-out.
Challenge accepted.



Carefully peeled back the old vinyl and inserted some baking paper between the card and padded vinyl.



Some moisture, steam and let dry with everything clamped straight.



After the card was straight and dry, brushed on some fibreglass resin (sans glass).
That soaked into the cardboard to stiffen things up. Also brushed in some fibreglass matting to help repair the cracked card.
Leave the baking paper in between so resin doesn't soak through the holes in the door card and form sticky / lumps to the padded vinyl.
Once that has hardened, remove the baking paper, applied contact cement, shallow staples and it was good to go.

Refinished the vinyl, handle and map pocket with my favourite Duplicolor Medium beige paint.
Mentioned before Duplicolor medium beige is a close match to Natur.
But slightly more 'browny' whereas Natur has that slight 'pinkiness' to it.

Some pics to show the colour difference.
(faded Natur at the front and medium beige refinished card at the back)





Also some new internal window rubbers to set it off and help reduce window rattles.



Now I have to do the other 3 cards to match :)

[Albie325]

Nice work, good to know how you repaired yours as I've needed to fix a door card crack in the past and like the way you did it better.

[Tzantushka]

Nice work, good to know how you repaired yours as I've needed to fix a door card crack in the past and like the way you did it better.

I'm not an expert - but it worked!

[Tzantushka]

Here's an A/C update for those following along...

The Sanden compressor was installed and fitted off.
Leak checked and all good.
So it was time to re-seal & insulate the evaporator housing.

I needed to replace the R12 Thermal Expansion (TX) valve with a R134a TX valve and replace the interior flexible hoses with barrier hoses.
The old TX valve was coated in a sealant tape from the factory, which had turned all dry and crusty.
It's also called 'cork refrigerant tape' or 'Prestite tape' A/C industry - helps insulate the TX valve and seal the housing.

If you leave the TX valve un-sealed, air can leak around the evaporator core and out of IKHS housing.
There's a cut-out in evaporator end-cap where the TX valve pokes through and connects to the evaporator high & low pressure hoses.



I'm not going for OE concours...
So no need to buy the factory goop tape to replace with factory goop tape.
Quicker and easier to use the leftover self-adhesive foam tape I used to insulate (lag) the evaporator return line.
If you're unsure what I'm talking about...





Not the prettiest - but sealed and insulated.

[Tzantushka]

And also here are some pics at the 'business end' of town.
Full disclosure - my vehicle does not have a front mounted oil cooler, so there is more room to route the hoses.

I still need to tidy-up some of the heat shielding for the hoses and secure the cables for the pressure switch & A/C clutch.
It's a bit scruffy for my liking.

Top view down on the RHS of the engine bay:



Shiny, shiny compressor:



Another view on the compressor connections:



Receiver drier detail:



Took the car away for the weekend on a road trip with the family.
It wasn't hot (24C // 75F) but was very sunny - so the A/C system got a run with the roof down and roof-up.

I'll need to take some ambient & vent temps to validate.
But definitely better than the Bosch Behr R12/134 system.
Initial observations:

1. Quieter compressor operation
The old compressor you could audibly hear clunk in and out.
The multi-cylinder Sanden unit is barely perceptible and smoother.

2. Feels like less drain on the engine
When the old compressor clicked in you could feel a difference in engine performance.
Yes, there's a drain, but not as pronounced.
Again, not hard data only seat of the pants / butt dyno.
Put it this way, no need to switch the A/C off when going up hills.

3. Better A/C cooling performance at idle
Even with the stock fan, idling in traffic the air blows cold.
With the parallel flow condenser, I have retained the original two-speed aux fan for the A/C.
Can always mod the aux fan to run on high later on.
Before, with the A/C switched on in traffic, the old system would struggle to keep the air chilled.

I reckon this was one of the harder jobs on the car as it took a lot of research, waiting for parts to arrive, and a quite a few hours in removing, checking, cleaning & refitting.
But it was one of the most rewarding though.
Glad I did it.

[luckybk]

love proper a/c. rare project for a vert owner, well done.

[Tzantushka]

love proper a/c. rare project for a vert owner, well done.

Thanks - always handy to have A/C in a vert.

Which brings me to the final A/C update.
Wanted to check the A/C was doing it's job and measure the vent temps before breaking out the manifold gauges...

Had to do the annual oil change and while the oil was coming up to operating temperature, checked the performance of the A/C at idle.
With the engine running:
- set the temp knob to fully cold
- A/C button depressed
- set the sliders to face vents only
- closed off the two outer face vents
- fan speed on 3

I don't have a A/C temp gauge, so used the high-tech meat thermometer - good enough for the moment!

Ambient temp at the time was 81 F // 27.1 C @35% humidity.
Temp inside the dash vent was higher (101 F // 38.3 C) as the windscreen was facing the westerly sun.
After the A/C system normalised, the air coming out of the dash vent was down to 62 F // 16.6 C - idling with the A/C on.
That's about a 10 - 11 C temperature drop...

After the oil change, took the car for spin to check A/C performance on the move.
Was later in the evening so the ambient temps had reduced down to 76 F // 24.8 C @45% humidity.
Same HVAC settings as above, but the A/C performance was much better.

After a few mins on the move air temp was approx. 48 F // 8.8 C.


Then after, 10 mins the system normalised.


Air temp coming out of the vent was low as 42 F // 5.5 C.
Approx. a 19 - 20 C temperature drop - much better...

May need a bit more refrigerant.. Will see how she copes on a hotter day.