When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
hello all ...working on a 04 s500. it overheated past 120C. did a coolant flush, new T stat, burped and bled the system. idled just fine. drove 15 miles, hit 120 again. I noticed the heat is not super hot. the fan is working. is the next step a new water pump and another coolant flush ? thanks for any help
First, see if you are actually overheating.An overheated engine feels noticeably hotter - you can feel the heat when you open the hood/bonnet. It will smell hot - usually noticeable. The Mercedes Benz gauges are usually accurate, but you don't want to spend hundreds on unnecessary repairs. Non-contact temperature-measuring guns are pretty cheap.
First, see if you are actually overheating.An overheated engine feels noticeably hotter - you can feel the heat when you open the hood/bonnet. It will smell hot - usually noticeable. The Mercedes Benz gauges are usually accurate, but you don't want to spend hundreds on unnecessary repairs. Non-contact temperature-measuring guns are pretty cheap. https://www.amazon.com/Thermometer-B...s%2C106&sr=8-3
I might be totally off, but does this car have a secondary coolant pump?
I had overheating issues, secondary pump was not working. No check engine lights or anything.
Your radiator fan controller is busted . Common problem . You may see it spinning but it’s a multi speed fan and the controller is not spinning it fast enough
Your radiator fan controller is busted . Common problem . You may see it spinning but it’s a multi speed fan and the controller is not spinning it fast enough
that would make sense actually.... does the controller come WITH the fan or can you replace separate ??
My issue.....the pump wheel had moved on the shaft of the water pump. It moved far inboard of where it is supposed to sit. Seems very odd to me - that was the cause.
My issue.....the pump wheel had moved on the shaft of the water pump. It moved far inboard of where it is supposed to sit. Seems very odd to me - that was the cause.
was it overheating while driving only ? it's just weird it never went over 85-90 while idling. then driving it, starts ticking upward. it hit 120c.
was it overheating while driving only ? it's just weird it never went over 85-90 while idling. then driving it, starts ticking upward. it hit 120c.
Went through a few variations. I think while the impeller was moving inboard. The impeller is fully confined by the pump housing - as compared to being fully outbound of the impeller housing. To me, very odd. But, if not driving, temps were normal idle temps.
Went through a few variations. I think while the impeller was moving inboard. The impeller is fully confined by the pump housing - as compared to being fully outbound of the impeller housing. To me, very odd. But, if not driving, temps were normal idle temps.
I think I will give the water pump a shot. the car has 200k miles lol.
that would make sense actually.... does the controller come WITH the fan or can you replace separate ??
you can replace separate but all Chinese parts are garbage
its better to get used original Mercedes fan controller from
junkyard or eBay and those are usually sold with the fan. It’s not your water pump it’s the fan Controller
I once used Benzninja with the STAR software to check my fan. Had overheating issues with other car.
He was able to spin up the fan through the software and it sounded like a helicopter taking off. Fan was fine in my case.
If you can get the software you will 100% know if the fan isnt spinning fast enough.
