the expansion tank on2006 mcs was empty and i am trying to figure out the cause. i undertand the termostat is a suspect, but could not find where it is. can someone send me a pic to show where the thermostat is?

thx

 

You could go to www.realoem.com and look at the diagram for the engine:cooling. It's on the right side. I'd think you'd be able to find it if coolant was leaking there.

If you are losing coolant, it should be obvious where it is getting out at, unless it is leaking into the oil internally. Check the dip stick for evidence.

The earlier coolant bottles were known for losing the seal between the upper and lower halves and the coolant would leak down the heat shield to the ground. I replaced mine for this problem and the new reservoir has lasted longer the original.

Best of luck searching.

 

It is on the driver's side of the engine. Right and left when describing a car is confusing. Is it right or left when looking at the front of the car or the rear? Of course I am making the assumption that this is a car made for the U.S.

 

yes it is a us mcs 2006. the engine bay is so crowded that it is even difficult to trace the coolaqnt lines. it appears that the coolant tube going to the bottom of the radiator is on the driver's side ( left side) so i guess the thermostat is also onthe same side of the engine bay. a pic would really help.

 

Do you have small puddles of a blue oily substance under you car on occasion? There is a known problem with the thermostat housing & gasket leaking and it is VERY hard to see and trace. I park my MCS in the garage and it was easy to see this stuff on the floor. This problem plagues the R53 Mini and is covered under warranty. I had the housing and gasket replaced 2 weeks ago at the dealer under warranty after getting diagnosed in these forums.

Check out:

https://www.northamericanmotoring.co...d.php?t=157424

HTH,

Good luck...

 

I recently had the '05 MCS thermostat replaced under the extended warranty... my expansion tank was empty and the motor temp would go to hot when sitting at a stop light. My mechanic noticed the leak while performing a safety inspection.
Apparently the thermostat is a common failure item. Good luck.

 

Car descriptions are generally based as if you are sitting in the car. Right= passenger side; Left= driver side (US) or vice versa if right hand drive car.

 

Sorry, I stand corrected. I generally describe it based on me standing in front of the subject with tools in hand.

Good luck banyan.

 

i found the thermostat but it is bone dry. i could not really see under the part but was able to slip my hand under it but no wetness as I can observe. I do not think I have a thermostat leak problem. any other suggestions?

 

You will have to bring it to someone to have dye put it and have it pressure tested.

It is strange that you are using up the antifreeze in the reserve and there are no puddles anywhere as evidence.

Did you confirm that the reserve does not have the leaky seam?

 

When my thermostat housing leaked it was difficult to determine because it would seem to only leak at night when the engine was very cool. It did not seem to leak when the engine was warm. I could not get my hand around the thermostat housing well enough to feel any coolant. I did see a little white residue (dried/cooked coolant) near the housing. The only other indication I had was a puddle in my garage, every once in a while. The leak eventually got bad enough that I got a puddle every night. If you park in different places each night or somewhere were the coolant will not puddle (slight hill or porous surface) you might not see the leaking coolant.

 

My experience was the exact same as quikmni. It was a $2 gasket to blame.

 

looking from under the car with the skid plate removed, it appears the coolant leak is coming from the water pump area. it is very difficult to see the source as it is very tight in there. is there any common issue with water pump leaking?

 

My MCS also had the water pump replaced under warranty as well.

If your car is still under warranty you should make an appointment and bring it in for service. Make finding the problem their issue instead of crawling around under the car with a flashlight like I did! It is a PITA to get the car to the dealer, but the job gets done without any guessing. Unless the diagnoses and repair are on your dime...

 

Good day i just had mine replaced thermostst and gasket which resolved
the problem .I was informed that the gasket has been upgraded as a result of
many of us having this problem .The housing was ok . Since i had the service manger in a good mood i brought up the subject of mushrooming
He advised the from end is just to heavy .I advised him of my fix.Pull it down from the inside and use the m7 stb .He advised that is what they do as well pull down from the inside but that is it .They will advise the plates or the stb but that is it .He also advised the run flats don't help the situation .