Replaced the thermostat on my '09 Clubman on Friday. The next day I check the overflow and it's low. For the next couple of days I repeat the process of refilling coolant [shop is closed on the weekends]. Then I notice a pattern where the coolant is leaking overnight, previously it only leaked when driven.

Took it back in today and the tell me it's leaking [bad] where the coolant transfer tube connects to the water pump. They said they checked the water pump during the previous inspection / install but said it was fine.

I know the two parts have a tendency for pre-mature failure but the timing of the two seem questionable. I suppose it could just be bad timing, given the track record, but is it possible they broke something during the thermostat install? The owner is on vacation, when he returns I bring it to his attention.

 

I don't know what you expect us to tell you. Of course it's possible they broke something during the install. More likely, it is just a coincidence. Cars have thousands of parts and components on them, they won't all break in neat little intervals.

 

When they touched the water pipe it might have cracked. it happens,

https://www.northamericanmotoring.co...rmostat-6.html

 

^^ Thanks a lot for the link. Obviously I have no idea what happened but I just found it odd that I was only losing coolant when driving and then after the thermostat install the leak was much worse - as noted in the thread where the guy broke the coolant transfer tube during re-install of the thermostat.


"Mine was really stuck and was a huge nightmare separating."... "The hardest part for me was getting the old thermostat to separate from the water pipe going to the waterpump."... "common failure"... "One thing to note. I broke the water pipe on my car where it goes into the water pump. It sounds like this is a pretty unusual failure. I noticed it because after replacing the thermostat I now had a much worse leak".


When I asked the mechanic he said they checked the water pump and it was fine or they would have brought that to my attention and suggested a replacement ATST. And now three days later they diagnose the water pump as "failed".

The owner is on vacation and I'm taking it back in Monday morning but I'm going to ask the lead mechanic to check if it's just the transfer tube that needed replaced. I'll bring up the other issue with the owner.

 

Welcome.

Yea, i did the water pump right after , same time , because i pressurized the thermostat and then the plastic water pump leaked, all in our thread linked.