Installation of auxiliary fans

[mixturegro]

I want to ascertain if I may transfer the auxiliary fans from a W208 to a W210. My primary concern is to the necessary modules and wiring required for this installation, considering that both vehicles are dated 1998 and have the older twin motor fans.

[partexpat]

If the component numbers are same, you should be able to proceed.

What issue is there with the auxiliary fan in your vehicle? What evidence indicates that it is the auxiliary fan?

Only one motor is included in the auxiliary fan assembly; the other is passive and rotates via a belt mechanism connected to the main motor. Consider relocating the motor from the donor vehicle to your automobile and replacing the belt simultaneously.

[mixturegro]

The W210, to my knowledge, was never equipped with auxiliary fans (I am uncertain if they were originally included and subsequently removed, but it appears unlikely). The auxiliary fan assembly I intend to install features two operational fans, with the corresponding codes for the fans and shroud being 2025053355 and 0015001293. I primarily seek guidance on how to detach the fan cables and their controller from the W208 and whether I can connect them to the W210.

[partexpat]

Acquire a fan unit from a W210.

https://www.pelicanparts.com/techarticles/Mercedes-Benz/17-WATER-Auxiliary_Cooling_Fan_Belt_Replacement/17-WATER-Auxiliary_Cooling_Fan_Belt_Replacement.htm

[partexpat]

I am unfamiliar with Romania, however you may get one on eBay or a similar platform if you locate an authentic used item.

The compatibility of the fan control module for the W208 with the temperature control unit, which regulates the fan unit for the 1998 models in the USA, is uncertain. The non-USA W208 may have a different configuration.

[mixturegro]

I will likely get a W210 auxiliary fan unit; however, I would have chosen the W208 unit due to its superior longevity and cooling capacity, which I currently own.

[partexpat]

I reside in Florida, and the auxiliary fans seldom activate, mostly for the temperature control condenser, which is tied to refrigerant pressure.

Ensure you get the auxiliary fan unit for 1998 and after, since the connections are inverted relative to earlier model years. Altering the polarity by severing and reconnecting the fan's wire is possible, although it is preferable to avoid this action. Connecting a 1997 fan to a 1998 W210 will direct the airflow towards the front grille instead of the condenser, unless modified.

[mixturegro]

I will contemplate this matter for some time, as my primary concern is the temperature fluctuations, which reach 90-95 degrees on the dashboard and 100 on an OBD2 scanner while in traffic, compared to a stable 80-85 degrees on open roads. The air conditioning is of lesser importance to me, as it complicates city driving, and the fans are unnecessary on the highway.

[partexpat]

Replace the thermostat, if necessary. Verify the functionality of the viscous fan.

[mixturegro]

I will reexamine the fan this week and replace the thermostat along with its housing once I determine the appropriate model, as I am unable to locate one that activates at a temperature below 86 degrees. During my last inspection, the fan operated normally, albeit somewhat slowly at 80 to 90 degrees with the air conditioning off, and functioned rapidly with the air conditioning on, with the engine temperature being a few degrees lower when the air conditioning was engaged.

[mixturegro]

Regarding the thermostat selections, I discovered a 71-degree thermostat that was previously out of stock. Should I choose the 87-degree or the 71-degree, given that both are from the same manufacturer (Mahle)?

[partexpat]

The engine thermostat specification for your vehicle is 87 degrees Celsius.

The engine coolant temperature (ECT) working range is 80 to 100 degrees Celsius, indicating that your vehicle's ECT measurement is within specifications.

71 degrees Celsius falls outside the acceptable limit and should not be used.