M20 fan clutch (defective from the box?)

[zaq123]

I need help to figure out what's happening with my overheating issue. New built, coolant was vacuum bled so I don't think air pockets is the issue, I think...
45F outside temperature. When driving, coolant is around 190-195F, middle position of the gauge. When stopped, it climbes to 207F-210 based on my ECU (about between middle and the next line on the gauge). I'm yet to let it got past 210F so I'm not sure where it would actually stop. Temp. goes back to normal when the car is in motion.
My first clutch was new Sach , manuf. date 2018. When engine was hot, I was able to stop it with a piece of cardboard and could hold it with my hand after that. Figured bad clutch. Maybe was stored in the wrong position? I saw a little oil around the pin, where the thermoplate is. Ok, replaced it with new Meyle (china made these days). No signs of oil. The same overheating issues. And I'm able to stop the clutch with the cardboard and hold it with my hand just like Sach.

Two bad clutched out of the box?? What's your thoughts.

[digger]

wouldnt be the first time they have been bad out of the box

the clutch fan essentially has no idea the temp of the coolant, the temperature of the clutch itself (metallic strip)matters. Presumably the radiator has hot coolant flowing? i am wondering if you get it to 210F and shut off the engine how hot is the actual clutch? with 45F there might be a decent lag between coolant temp and the temp of the clutch. Also can put a heat gun on it and periodically monitor the the temp with a infrared laser thermometer to see if it starts to lock up kind of bench test

you can also add more silicone

[McGyver]

Any chance the coolant pipes are plumbed backwards somewhere?

[reelizmpro]

I wouldn't doubt it nowadays. If it fails the newspaper test, then it's not effective. Before replacing it again though, you want to check to see if the system is holding pressure.

[zaq123]

Any chance the coolant pipes are plumbed backwards somewhere?

no everything is as it should

[zaq123]

I wouldn't doubt it nowadays. If it fails the newspaper test, then it's not effective. Before replacing it again though, you want to check to see if the system is holding pressure.

system is holding pressure and vacuum, totally vacuum bled with no air when filled (vacuum filled back up with the coolant) and then pressurized thru coolant tank cap (with the heater core valve open) to insure that only coolant comes out from the top of the radiator (thin hose).

[zaq123]

So I let her run past 207F. Also I'm using BMW 80° C Thermostat - Mahle Behr 11531713040. Looked at the receipt to remind myself.

My observation reading temps thru Haltech ECU (new OEM NTC bosch sensor is correctly calibrated for Haltech btw):
cold 56F start. Fan blades can't be stopped by the cardboard. Warm up to about 90F - clutch fan disengages and can be stopped. Not sure if it takes time for the clutch to disengage/displace silicone oil hence the result??? Temp climbes to 207-208F, clutch engages/fan can't be stopped by the cardboard. Temp drops to 197-198F - clutch disengages.
I witnessed a consistent repeat of the above about 3-4 times, same temp range, same results.
Could it be that Meyle is using a temperature plate that has a properties for a modern-ish car? Those numbers would be perfect for like e46 spec for example (coolant temp 194-230F) when m20 is like 175-200. Basicaly my dash gauge is at half mark when moving and it's like half way to 3/4 mark when idling. Which I think is a little high for M20.

Sach clutch I had which I thought was defective is 2018 manuf date. I never played with it and just replaced it. I found another Sach fan clutch which is new and was manuf in 2002. I'll give it a shot I guess. Luckily I can still return that Myele Chinese unit