seif khalil

Hello Guys, I am driving a s550 07. The fan speed issue started three weeks ago. It started gradually increasing. It increased one time for 5-10 minutes and then the same for the second time and so on. And now it happens every 5 minutes. I thought at first it is because it needs flush because from the previous owner the radiator is left really dirty from the antifreeze. You can see brown mold with the water. So can anyone advise me, should I go to an electrician or should I flush the radiator?
Thanks a lot.

alx

Car needs to be read and coolant temps observed. Your fan most likely is kicking on high because your coolant is too hot. If you have gunk in your coolant you should really do a flush and take it from there.

DaveW68

Thermostat might be bad too. Change that out when you do the flush.

alx

if thermostat is bad "gradually increasing" fan speed is not typical... even if stuck close...

DaveW68

Understood. But since he is doing the flush, changing it out since it's a cheap part would be warranted IMO.

seif khalil

Thank you for your reply guys. Now I went to the mechanic and he ran checks on everything and hes telling me now that I need to replace the oil cooler because it leaks oil and it is the reason behind the loud fan. He is going to flush too because of the oil leakage. But it is going to be an expensive job. So I am just checking if he makes sense?

alx

it does make sense... unfortunately