Well not necessarily. I personally have worked on several mini's that have been running around with the fan on back to front. I can't actually remember if any were to do with a cooling issue but i do remember at least 2 times i've taken a motor out and started stripping it down to notice the fan on wrong and has been so for some time.

Are you sure you have the right temp sensor in it?

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Ryan Filippi
Minis In The Gong
[email protected]
www.minisinthegong.com.au

oh whoops, I got confused and thought you'd written about putting the thermostat in upside down - reading your post again, you talked about the thermostat, then the fan as separate paragraphs, but I merged them in my mind..... weird

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did I tell you that I won a trophy?

The thermostat is either a 72 degree or a 74 degree, I can't remember which.

Today I checked the fan, it is pulling air from the engine bay and pushing it out the vent into the wheel arch - so it seems correctly fitted.

I also used some radiator flush and cleaned out the cooling system but all the coolant coming out looked fine.

If the overheating is caused by it running rich, wouldn't the temp drop when it was left to idle?

No, I'm not sure. I have tried other temp senders but they have either indicated much hotter or much colder.

Is there a way to check the sender is correct?

Uncommon but your running out of options so...

One of my brothers had a problem with over heating on there car. What they figured out was his gearbox pretty much didn't have any fins on it. So the oil wasnt cooling and was getting very hot which flowed on to affect the temperature of the motor. He hooked up an oil cooler and it helped a lot.

So what are your fins on your gearbox like?

Do you have an oil cooler on hand that you could just test to see if it makes a difference on your car?

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As per the first reply, lean mixture makes the engine run hot. Rich runs cool. Lean mixture can also make the car backfire (on my last car it would backfire the most when coasting down a hill in gear)

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If your car has the plastic fan Just double check again if you have it fitted correctly using this "how to"

http://www.ausmini.com/forums/viewtopic.php?f=25&t=72688

The fan will still push the air in the right direction if fitted incorrectly BUT the fan is more efficient when correctly fitted due to the curved design of the individual blades and where they sit relative to the shroud. It's a common mistake because the "neat" side of the fan centre actually goes toward the water pump, not toward the radiator as you would expect.

May not be the whole answer to your problems but when it comes to cooling every little bit helps.

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68 Morris Cooper S Mk1 (*ex 78 1275 LS 4th last built, 70 Morris 1500 OHC & 70 MiniMatic)

The fins on the gearbox look perfect, like everything else on the car, it is brand new

I don't have an oil cooler handy, but maybe I need to buy one anyway?

How hot is the oil now?

Don't fit an oil cooler, fix the overheating problem.

but is there actually an overheating problem????????!!!!!!!!!!!

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did I tell you that I won a trophy?

Have you tried another gauge ? Can you get hold of a good capillary gauge to compare readings ?

How do we know there is an ACTUAL overheating problem?
Could the gauge be showing artificially high due to an increase increase of say 10 degrees air temp?
I was under the impression the original sensor moves from med to 3 quaters hot with a difference of around 10-15 degrees.

As I said, I had the same problem and was stressing about it. I was advised to fit a Capillary temp gauge which has a solid tube of eytha (from memory) and that reads accurately.

For example a gauge like this:

http://minisport.com.au/prod986.htm

Link automotive in melbourne carry a Pricol branded one for about half the price, but it's not Smiths

agree with talfox- measure the temp/ test gauge first to see if it is misreading

Or you could just fit an oil cooler and a tropical fan like everyone else.