Can't Find Coolant Leak
 

I am finding a coolant puddle on the garage floor in the mornings. I have inspected the top side and underneath. I can only find small amounts of coolant on the bottom of the drivers side rear sub-frame. I can't find any coolant on any cooling components. Last night after driving about 100 miles I did an inspection. No coolant leak is visible from the top side and I jacked up the Mini and inspected from underneath and could not find any leaks. This morning there is a puddle and a small amount of coolant on the bottom of the drivers side rear sub-frame by the control arm bushing. I had to add about 8oz of coolant to the tank. Anyone have any thoughts on what to check? Mileage is right at 70k.

I just went thru something similar on my '08 Hatch. Driver's side leak - although closer to the front. Mine was a bad radiator I got replaced and it's holding fine now. Took me a while to figure out where it was coming from, since sometimes the leak would appear to be further back and then others more to the front. My thinking is that the leak traveled on some of the body hardware downhill/downstream to a low spot. Anyway, the problem was found when the dealer did a pressure test on the system. Frankly that's about the only way to know for sure so you don't just start throwing random parts at it. Mine had 122k miles, BTW.

andy

Its might be pooling on top of the transmission housing , which make it a little harder to find. Then when it overflows , it drain down the back and can hit parts of the lower sub frame. Check the thermostat housing on the bottom of it. Run you hand and check for leak and liquid , when the engine is cold of course. Linked to other locations to check.

https://www.northamericanmotoring.co...g-coolant.html

http://c1552172.r72.cf0.rackcdn.com/401887_x600.jpg

Thanks

Thanks guys. I took the Mini for a drive tonight to get the engine up to operating temp. parked in the garage, popped the hood and noticed coolant on top of the drivers side transmission. Looked underneath and saw a steady drip of coolant hitting the floor. The water pump for the turbo was running and when the pump shut off the drip slowly stopped. I jacked the front end up and inspected underneath. I am not certain yet, but it looks like maybe the inlet hose is leaking on the pump. Since the drip only occurs while the turbo water pump is running could it also be a thermostat housing as well?

My money's on the T-stat.

" popped the hood and noticed coolant on top of the drivers side transmission" I called that one. :)

I would do the main water pump and the T stat at the same time,. If the water pump is plastic on the outside. Change it and get the new design metal housing. Did both of mine while I was there and gtg now.

Thanks

Well, indeed it is the thermostat housing. I let the engine get to operating temperature and then did an inspection and I discovered coolant leaking on the top of the neck where the water pump pipe attaches to the housing. Just my luck it happened 2 days after my pre-purchase inspection. Sure glad I was not out of town while my wife was doing her 100 mile round trip daily commute to work or it could have been costly.

Thanks for the feedback gang pointing to the suspect. I replaced the thermostat in her 02 Mini and had to remove the battery box and the air box to get to it. I think I should be able to do this one in about half the time on the 02.

+1 If you can, replace them both at the same time and save yourself the headache. My car is still under warranty and although it was done for free, I was back at the dealership for the water pump maybe about two months after the thermostat was replaced.

Glad everything worked out

I am glad you found the link and all of us could help. Again doing both the T stat and the water pump at the same time helps down the road. Everything is linked above. Post up when you get rolling again. :thumbsup:

I have the same thing, I found it . look on the driver side it the thermostat housing there is a vent Bleed screw and temp sensor. after you have driver for sometime. take your flashlight look in that area . you will here the steam hissing and see the bubbling. if you do not understand this at 203-530-4568 Will Smith ant time

I ordered the T Housing from ECS this morning and should have it Friday. This is my first parts order from ECS and I checked all my online sources and I must say you guys are very competitive. I checked the water pump and it is Black, so I assume it is plastic. I will have to do that job in a few weeks and will order from ECS.

Thanks again.

Awesome,

Thanks , not only is it pricing but I am here to help and explaining what to check. :)

Black main pump is plastic, I would change that out also.

Thanks again.

I also have had great success with ECS. Great service. Good pricing. Only issue is duty while shipping to canada, but that's more UPS. Service and knowledge is great.

You are welcome. Thanks

Received the TSH last night and installed early this morning. Not a bad job at all. It took me about 1 1/2 hrs. There is a good video on YouTube. A couple of things. It is easy to get the clip out of the connector on the hose from the water pump to the TSH if the air box is removed. I didn't have to take the cover off of the wiring harness that covers the TSH housing. Inner hose clamps are easier to get off if the outer hoses have been removed. The lower hose to the turbo-leave the hose on the metal pipe to the turbo and when you have everything disconnected from the housing you can pull it out of that hose to the turbo. I used a 1/4'' drive ratchet with an extension to remove the three bolts and did not need a swivel for the bottom bolt. Easier job than I anticipated.

Glad you were able to DIY it. :) Hopefully my diagrams helped.