W124 engine cooling

[Dexter]

Dear All

My W124 E280 estate is running hot.

first stop was the cooling fan which I cannot hear cut in.

When engine is turned off from hot fan spins out in its own time but as engine cools (when off) it stiffens.

I then ran the engine holding the fan with a finger and as the engine temp rose it began to engage and tug free to a spin. albeit worryingly at a temp reading of around 115!! I believe this tells me that the viscous coupling is functioning ok. But it would be useful to know if they just cease operating when faulty or if they can work poorly.

I then spotted a fairly peristant coolant leak to teh left of the radiator dropping on to the floor would this be foxing the thermostat an in turn the point at which the coupling clutch cuts in.

Grateful

 

[kid-jensen]

Dexter,

The viscous coupled fan should start to couple long before 115 degrees. (more like 85-90)

The viscous units are pretty reasopnable at GSF and Europarts, so it's worth changing as a precaution.....lots of expensive stuff happens when the engine gets that hot..

You may be lucky with your rad leak in that it may be caused by excessively high temperatures, and will fix itself when the engine runs at something more reasonable.. It wouldn't affect the temperature that the thermostat cuts in.

Still worth keeping an eye on any leaks though, they have a habit of returning at inconvenient times.....

 

[mercedes328]

How easy is it to replace a viscous fan coupling on a 124.

They are £58 at GSF btw

 

[television]

Do a search here, there are many threads on it, just type in Visco

they cut in at 80c

 

[Old Hat Shop]

Aside from the fan issue, if you have a leak then the colling system wont be pressurized and subsequently it will run hotter.

I've yet to enjoy a leaking system that fixed itself.

 

[television]

Aside from the fan issue, if you have a leak then the colling system wont be pressurized and subsequently it will run hotter.

I've yet to enjoy a leaking system that fixed itself.

Patience, it will come one day