Okay guys and gals. The ‘06 R50 started overheating about a month ago. I decided to start with the basics. Changed the thermostat, didn’t work. Realized the fan wasn’t working, checked all the fuses and relays, didn’t work. Changed the fan, fan is now working but still overheating after about 5 min of driving. I’ve opened both purge valve to get any air out but I’m stuck. I was going to pull the thermostat again in the morning to be sure I didn’t do anything wrong there. Other than that, I’m stumped. Any thoughts?

 

When was the water pump last replaced?

How about the expansion tank and cap? Is it leaking?

 

Not sure on the pump. I just replaced the serpentine belt and the water pump seemed fine at that time. The heat fan is working doesn’t that require a functioning water pump? No leaks at the expansion tank.

 

The water pump is driver off of the supercharger. If I remember right, there is a little plastic gear that drives it. Maybe the gear got tore up?

How did you check the water pump out when you changed your belt?

 

R50 with SC? I can be wrong because of my reading incomprehension. To OP, make sure you install the thermostat correctly, and not to flip it 180 degree. And you are exactly right that no cabin heat if the pump is kaput.

 

Sorry, I guess I missed that part...thought it was an R53.

 

If you are replacing the t-stat, replace the housing as well. I had an R50, took me a long time to troubleshoot my overheating problem. Housing was bad and the gasket just crumbled when I took it off. Make sure to properly bleed the system and only fill to recovery tank to the fill line.

 

My most recent overheating issue was simply the expansion tank and cap ... I have a stock of them, a couple of years ago they went on sale for like 60% off ... I got four.

The time before that was a bad fan resister, I got stuck in traffic and sitting on the highway waiting for an accident to clear I noticed steam rising from my hood and saw the temp had shot up, High-speed fan was not coming on. Luckily I was aware of the issues related to the problem and was able to avoid doing damage to the car while I waited to get moving again.

Best of luck.

Motor On!

 

My most recent overheating issue was simply the expansion tank and cap
I don't know if you've had an R50, they don't have pressurized expansion tanks, not to say the tank doesn't have a leak, they just are not pressurized.