Oil radiator installation. Possible troubleshooting solutions?

Can you share some pics of your installation when you're at it?
Sure will. I am going to be getting it up in the air on the drive hopefully today. I will take a look at options where to mount the matrix. I was watching this thread on a RS4 into a T5 and noticed their fitment, I am going to look at this as an option

Screenshot 2025-04-30 10.50.07.png
 
Agreed!
I’ll also carry a bunch of cable ties and a piece of plastic to place in front of it if it doesn’t work the way it is intended.

Or… do I just buy a remote stat and be done with it?
Closed internal engine circuit will aid engine warming and degassing of excess fuel.

AIf it was my van, 100% sure with a thermostat, opening at 100-105 degrees C.
 
So another way I can think of intercepting the oil flow is with one of the two adapter plates linked below, that will then allow me to use a thermostatically controlled oil filter take off sandwich plate to provide the flow and return for the oil cooler.

Oil filter adapter plate - eBay

Oil filter adapter plate

The only other way would be to fit a remote online thermostat, which would probably be the best way to go.
 
Last edited:
I think I’ve decided to use the HEL inline thermostat, it’s a little cheaper than the MOCAL unit, you get to choose what fittings come with it (AN-10) and it’s real purdy to look at too.
Temp options are;
82 C (180 F)
92 C (198 F)
102 C (216 F)

I’m thinking the 92 will be the best bet, get the engine hot asap, get the fuel off gassed quicker, and provides the protection from oil degradation in high load situations
 
Darkside thermostat opens at 80°

Oil Cooler is 13 Row

That puzzles me tbo. Why would you want to open an oil cooler at 80 C when the engine is not even at operating temp yet? This only slows down further warming of the oil without any reason and with an adverse effect. This seems a standard (I avoid ‘old school’) performance oriented setup. Probably fine for (highly) tuned engines but a lot less for a (close to) standard daily van used year round.
This is exactly the point that Redhead emphasizes too btw.
 
that does seem a little shortsighted on darksides behalf.
Out of interest, what temperature is regarded as operating temperature?
 
I think I’ve decided to use the HEL inline thermostat, it’s a little cheaper than the MOCAL unit, you get to choose what fittings come with it (AN-10) and it’s real purdy to look at too.
Temp options are;
82 C (180 F)
92 C (198 F)
102 C (216 F)

I’m thinking the 92 will be the best bet, get the engine hot asap, get the fuel off gassed quicker, and provides the protection from oil degradation in high load situations

I’d take the 102. You don’t need any extra cooling at 92 C. Not at 102 either but that’s a fine point for the cooler to start stepping in. Provided it doesn’t cool too much. Oil needs to be (well) above 100 C to gass out properly AFAIK.
 
that does seem a little shortsighted on darksides behalf.
Out of interest, what temperature is regarded as operating temperature?

That depends on the obvious variables like ambient temp, engine type and use but as a rule of thumb I’d say 95 C and up.

For some context; single turbo 150s and lower run significantly cooler than the BiTurbos - hence they have a lot less problems / are much less vulnerable in the longer run. Last summer in the south of Italy at 40 C ambient, my ‘24 DNAA 150 fully packed camper hovered between 98 and 113-115 C during long near full throttle climbs. While I had decided to get a Redhead kit fitted, I turned out this engine doesn’t get hot enough to need an extra oil cooler. With the BiTurbos the oil temperature operating window looks very different as most owners know too well. Power = heat, there’s no way around it.
 
Last edited:
One thing that I’ve always been concerned about it is thermal shock, if in winter, the van is happily operating at 100 C outside ambient is 0 C, then we climb a hill which increases the oil temp to 110 C the stat will open allowing very cold oil into the system, I know the stat won’t just open like a solenoid, so hopefully it will open slowly to allow cold oil into the system.

I think I’ll ask HEL what behaviour characteristics their thermostat has over all three, if the 92 C starts opening at 92 or is it fully open at 92?

I’ve always been told never to put cold oil into a warm or hot engine because of this.
 
Woo hoo
The rad and oil lines have arrived
Looks like I’ve got some work to do this afternoon.

I’ve got the HEL remote stat on order, I’ll also need some more fittings, but I’ll get it mocked up before I go buying blind.

IMG_8929.jpeg

IMG_8930.jpeg
 
So another way I can think of intercepting the oil flow is with one of the two adapter plates linked below, that will then allow me to use a thermostatically controlled oil filter take off sandwich plate to provide the flow and return for the oil cooler.

Oil filter adapter plate - eBay
Although I've already denigrated them...

Take of plates of this type to convert Smart cars to spin on filter are less than £15 on AliExpress...


If you were after a thermostatic item etc I'd steer clear, but as a screw in passive adapter these are very good, well machined, and would save a packet. In their day they were very popular with Smart owners and used a few myself (serial W450 owner BITD.)
 
I will indeed.
I love a little project like this.

So the cooler, lines and fittings arrived today, I’m still waiting on a set of 4x m6 vibration isolator feet to protect the low temp radiator.

The HEL ‘stat and a few fittings where ordered today, I should have them by Tuesday.

Shiney new Setrab SLM 10 row oil cooler

IMG_8929.jpeg

This is where it will be fitted, the pipework routes may be a little congested, ill be able to work on that once I get my new (yet to be delivered) inlet manifold fitted.

IMG_8932.jpeg

This is 12ft of stainless braided, black nylon outer braided oil lines, a few AN10 fittings, and 2x mocal mounting brackets, all very nice quality.

IMG_8930.jpeg

I’m really looking forward to getting into this!
 
Thanks for publishing this!
What I would find very useful is if you list the parts and source of the parts you used.
Can't wait to see how you route the oil lines.
 
Back
Top