CaliBenzDriver

This mod is directly beneficial for warm weather above 90F... tropical and all.

It naturally is a perfect XMas gift for Bali weather
Merry Xmas Master Surya and freiends - Thank you for pump solenoid itchy fingers discovery!
My engine is now transformed !!


Here is my mod to max out coolant circulation using our existing electric pump.

I don't know how much life this pump has before it leaks - I am going to try running it from now on, specially beneficial in Summer and stop-N go traffic.



electric circulator


SAM menu option


Let this engine block get cooled

W212-AMG guys use a mod GND bypass to force the relay ON with ignition. They've reported cooler temperatures.

I was just borderline un-impressed about my hyperactive radiator fan. My temps are under control

Fan + with TStat

Controlled temperatures are associated with good oil viscosity for a perfevt oil film.

As usual experimental testing may well hurt your engine systems. We don't know, what we don't know.

CaliBenzDriver

Requirements are to use a SCANNER programming tool to manipulate adaptations.
Hardwire mod is still practiced but now we have the more elegant 5mn software toggle.

Think of this as Spring: pump-ON and Winter: Pump-OFF

To work on this I've used the Launch C-Reader Elite recently recommended by @S-Prihadi


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S-Prihadi

Cali,

I think if AMG engine , if they speak of auxillary coolant pump, it probably be the aftercooler coolant pump.
I have it too, because of the water to air aftercooler on my engine.

This is the pump:



If I recall correctly, that small pump you pointed out is plumbed ( for my engine ) to make sure HVAC heater core hot coolant can circulate faster when HEAT is choosen in HVAC control,
and probably during ECO start stop engine SLEEP mode , the HVAC heater core can still be warm ( for cold country ).
This baby pump does help coolant suction flow as its output I recall is to mechanical coolant pump circulation suction pipe Tee.
I said Tee because for M276 3.0 Turbo, this Tee is also for the return of the 2 water cooled turbo coolant hose/pipe.

CaliBenzDriver

Here is the original W212-AMG thread, where they hardwire that pump to help remove heat.

I give them full credit for that - I have not validated how much cooling improvement it brings.

I will be glad if this helps the ECU not spin the fan.

S-Prihadi

I see, they did mention intercooler pump. I have the same stand-alone relay on my engine bay, but I never really dig into its wiring diagram
Based on my logging, if for my engine in Jakarta.... which at traffic jam the IAT temperature even with that pump supposedly claimed by OP running starting at approx 43C, I will always be at 55C to 60C
insane hot IAT due less airflow from car velocity.

At 80KM/H or higher at highway and it must be after sometime.... only then the best IAT can be achieved at approx +12C to max +15C above ambient temp.
So its more of airflow issue for me instead of waterflow. OP first post indicated 15C ambient temp during his test...wow so nice and impossible for me ...LOL.
25C is as cold as Jakarta get at night say 2 AM ish.

My result is quite inline with OP but at cruising speed ( due to high ambient temp )....with OP 15C becoming 38C or 18C delta after a few hard pull he said and better at cruising speed.
I bet 60MPH constant speed is not a problem for his road traffic condition.

Heat soak is what I hate the most for my engine, a mere fuel stop will make my engine + all aftercooler components soak heat so much, but not a suprise
since my engine bay temp becomes 85-90C if near zero car speed and can be as low as 50C at 80KM/H .

CaliBenzDriver

Well I have a DiveBuddy who came up with a solution to remove engine heat.... it's becomed a mod on YT Channel.

Your car gets heat soaked when you stop the engine - Ok master lets fix this good together with simplicity.

First of all BEFORE WE STOP THE ENGINE, we need it not to artificially store too much internal heat.

In the AMG section an experimenter testified that his garage no longer gets super-heated by his car after parking. I have the SAME EXPERIENCE!
So the PUMP SOLENOID IS ALREADY HELPING YOU in that respect. The core is not uncontrollably super-heated


> PUMP IT UP:
We have an existing baby coolant pump (easy on batt) that moves coolant on demand.


> Run 15mn Longer:
-- Currently pump stops when car enters reduced-power eary sleep mode... 2mn

-- We can wire a dual relay to switch pump (DPDT)

-- Relat power suppled through a 15mn timer.

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> ADD ADDITIONAL CIRCUITS:
-- You've mentioned inter-cooler coolant needs

-- we know about bank2 head host the heater outlet

Let's replumb your cooling for efficiencies or simply additional control.


Since moding my M276 quit smelling an active coolant leak. I have not mapped the pump line, I see it go to the engine rear. I can guess it draws heat from the bank2 through the cabin heater core.


Where can we add an aditional pump to circulate your bank1 with engine off Tstat open?
Is there a matching engine plug in Bank1 matching plastic pipe-adapter position in Bank2 ?


> COLLECTION FOR MAX GRADIENT
You know about the nature of heat transfer through heat exchangers. The transfer is based on differences, right?

We max out the heat gradient to max out the heat transfer.

Practically we need to circulate as much heat in the radiator hopping to get a higher heat gradiant for 25°C Jakarta air exchange.

Thank you MB for doing the exact opposite: pump off, no piston squirting ECO soakings,....

Here is a glowing red at 20.000.Rpm

S-Prihadi

It is a dilemma for me to mess with that small heater core coolant pump you speak of.
If I run that pump, the heater core inside my HVAC core will get better supply of 95C coolant in them and I loose HVAC efficiency from the "heat leak".
That pump when not active, its like a restrictor to coolant flow, not a complete blockage but slow down coolant flow and is to my HVAC benefit.
If I mod that pump electrically, I must first mod the plumbing as such this baby pump suction will be for turbo core coolant return pipe instead of now HVAC heater core.
To note : turbo core cooling is by engine radiator system. Only charged breathing air is separately cooled with aftercooler on its own circuit.

Then come the 2nd obstruction. The MAP controlled thermostat and the 800Watt radiator fan.
Based on my previous test logging temperature input and output of the radiator and seeing fan command speed, MB heater R48 on the thermostat and the radiator low fan speed
is leaning towards 95C coolant temperature most of the time and I can't do anything about it.
Xentry will show you ECM coolant target temperature, first when engine is cold it will target 105C coolant temp...yep, 105C.
Later when engine is warmed up, ECM will target lower than 105C....like 90C or so, but coolant temp will then be 95C for a 30-32C ambient temp region...me.

The key in my engine ( not aftercooler ) cooling system lies a great deal on the heater R48 on the thermostat and the radiator low fan speed and not the amount of suction allowed for the mechanical
coolant pump. I mean MB kinda "choked" my cooling system to make sure my engine run hot at 95C most of the time. Afterall, mechanically my thermostat will only start to open at 95C and full open at 103C.
That is why R48 thermostat heater need to be healthy for when ECM wants 95C coolant temp or lower.

Post #59 here shows how my ECM loves to be stingy on coolant circulation volume where you can tell by R48 heater control* ( * 100% means not active and 0% means fully ON R48 heater ) ) and fan speed.
https://mbworld.org/forums/e-class-w...ml#post8841287

From the day at the track I did in 2020, I discovered my cooling system can not handle more than 3rd lap of agressive driving at 32C ambient.
So by 9KM or 3 laps, the 120C coolant temperature I get..... can't go away and that made me slow down the car. So both ways I am kinda screwed.
There is not enough cooling for hard use, while in normal or moderate use MB design my engine to run hot.....I loose both ways

Now you see the bottle neck I got from MB own algo/design ?
I don't know how a non turbo M276 3.5NA coolant temperature management is like ?
Need someone with the M276 3.5NA engine be itchy handed enough to record his Xentry for a 30 minute drive from cold , prefer in hot summer of 30C or hotter.

At one time I had the idea to do it the BMW M engine style, extra 2 small radiators , but I gave up due to space and complexity.
Aftercooler extra cooling I was chasing, not engine radiator.

When I am back in Jakarta, I will dig into what is the actual IAT temperature an M276.820 aftercooler pump will be trigerred at ?
I do not believe it is a simple as a FIX 43C, there must be other parameters taken in by the ECM because of needing to heat up engine faster during cold start or something along that line.
Knowing air density is a turbo #1 friend, I am sure the ECM will want IAT to be as cool as possible when engine has reached its operating temperature, probably not freezing cold kind of cool,
but 43C is too hot in my opinion for an SAE "standard day" horsepower calcualtion.

SAE J1349, which is the most common correction factor, uses an ambient pressure of 14.4 psia ( 993 millibar ), an ambient temperature of 77 deg F ( 25C ), and a relative humidity of 0%, which results in an ambient Air Density value of 72.2 lbs./1000 ft^3 ( 1, 160 grams of air per 1,000 liters of air )

.

BenzV12

Kudos to you , this is probably one of the most useful mods you have ever done to your car
Merry Xmas and Happy New Year