Fault Diagnosis Help...

[mike9009]

Posted in MINI forum too....

Just a little help required diagnosing a fault with my R56 clubman S (2007).

On Friday morning (commute to work) the heaters would not throw out much heat.

Saturday morning, I found the coolant low, so topped it up (I did not have time to take it for a run). Not noticed any dripping or wet patches anywhere.

This morning I took a short run (about a mile) to get some petrol. Stopped at petrol pump and fan running continually for a lengthy time. Came straight back home and fan running again. (Fan is running with engine running and then for several minutes once stopped)

I suspect the water pump?? Or maybe thermostat? Any thing mentioned give a clue to one or the other?

How much should I budget to get it fixed in a local indie?? Anything else it could be??

Many thanks


Mike

[stevieturbo]

History ?

So no sign of a leak ?

No indication of how much coolant it is losing vs time ?

No mention of rising or incorrect temperature on gauge ?

Fans will often run all the time if the ecu/engine is in a limp mode. Seeing as you dont mention about rising temperatures, this seems most likely.

So a remote diagnosis on supplied info...is impossible and certainly no way could you say water pump etc etc.

Presumably there is a functioning check engine light on the car ?

There could be either electrical, or mechanical problems. Or both.

[mike9009]

stevieturbo said:

History ?

So no sign of a leak ?

No indication of how much coolant it is losing vs time ?

No mention of rising or incorrect temperature on gauge ?

Fans will often run all the time if the ecu/engine is in a limp mode. Seeing as you dont mention about rising temperatures, this seems most likely.

So a remote diagnosis on supplied info...is impossible and certainly no way could you say water pump etc etc.

Presumably there is a functioning check engine light on the car ?

There could be either electrical, or mechanical problems. Or both.

Car has 47000 miles, but used on a daily basis during the week (just started longer commute last week (30 miles per day). Full MINI service history, last completed Nov 2014. No noticed leaks. No warning lights. No temp gauge on the R56 MINI. All lights come on during ignition start-up.

Heating worked Thursday and did not on Friday.

After the short run this morning the engine was warm to touch, but coolant in expansion tank was stone cold. No noticeable loss of coolant this morning.

Usually check coolant every 500 miles or so - no noticeable coolant loss until I noticed it yesterday. It needed about 0.5L to top up. (checked regularly due to oil usage from new on the R56 engine!)

Thanks

Mike

Edited by mike9009 on Sunday 1st March 12:46

[mighty kitten]

Change the cap , done loads of them . Cap starts leaking which lets the coolant level rise overfilling the tank on the bulkhead . You mighg see some residue on the overflow tank . As it cools it sucks the coolant back into the system minus what's been pushed out of the tank until the level drops enough to stop the heater working properly . Temp gauge will always read as normal . Around £15 from bmw and some factors carry them but I go with genuine ones . Rads do leak on early cars but I've done a lot more caps than radiators and water pumps on these

[mike9009]

mighty kitten said:

Change the cap , done loads of them . Cap starts leaking which lets the coolant level rise overfilling the tank on the bulkhead . You mighg see some residue on the overflow tank . As it cools it sucks the coolant back into the system minus what's been pushed out of the tank until the level drops enough to stop the heater working properly . Temp gauge will always read as normal . Around £15 from bmw and some factors carry them but I go with genuine ones . Rads do leak on early cars but I've done a lot more caps than radiators and water pumps on these

I am not sure whether this is the right cause? Just gone and started the car (cold again since this mornings trip). If I start it then immediately stop - the fan is running after switch off. So perhaps it is not overheating and there is an electrical gremlin somewhere?

Mike

[mighty kitten]

Where did you add the coolant ? Exp tank or the cap on the side of the motor ? Did you open the bleed screw on the top hose ?

[mike9009]

mighty kitten said:

Where did you add the coolant ? Exp tank or the cap on the side of the motor ? Did you open the bleed screw on the top hose ?

I added straight into the expansion tank.

However, I have taken it for a longer drive this evening. (having noticed the fan was switching on from cold), so assumed it was not caused by overheating. This seems to have solved it.

I imagine you will tell me I had some air lock somewhere that has cleared after a longer drive??

Heating is toasty hot again, fan not running either when cold or hot... My paranoia about toasting the engine probably kicked in. Sorry!!

Thanks for all help

I suspect the only question is where the coolant went in the first place? I will keep a close (daily) eye on this to make sure everything is food....

Mike

[mighty kitten]

Ignore all the above , just noticed the r56 bit , cap issue is the older engine . Done a couple of radiators on the later cars n/s lower corner is where they tend to go

[mike9009]

Just to complete this topic, in case others come across it.

I had a coolant leak, although it was not always obvious looking under the car. However, it was obvious, after checking the coolant level daily and topping up with about 0.5 litres.

The thermostat housing was leaking. To change it looked a right pig, so I cheated and went to BMW who changed it for £205 fully inclusive. I think they quoted me incorrectly as they charged for only one hours labour!

Mike

[Sardonicus]

Plastic bodied water pumps give loads of agro on these gland seal failure leaking coolant out of the vent hole when parked up and cool get it pressure tested