11 replies to this topic

[DeadSquare]

Has anyone seen their Mini oil temperature exceed 150C ?

[Steve220]

With an AEM X series oil temp gauge, never seen mine go above 120c. If it was going to 150c, you've got some serious issues!

[Midas Mk1]

The replacement senders from minispares are water temp senders not calibrated for 170’deg gauges and read high, sorted mine using an mgf sender, did a bit of searching around.

For reference ran mine in hard on tuesday (new rings), a good 100+ miles of thrashing, didn’t go above 90 with my oil cooler.

Edited by Midas Mk1, 18 April 2024 - 07:17 PM.

[Quinlan minor]

Absolute motorway hammering, in the height of Summer, can get mine a little above 120°, but nowhere near 150°.

 

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Edited by Quinlan minor, 18 April 2024 - 07:22 PM.

[DeadSquare]

With an AEM X series oil temp gauge, never seen mine go above 120c. If it was going to 150c, you've got some serious issues!

Thank you.  That is encouraging, but from where in the engine is the temperature information being sent ?

[Quinlan minor]

Page 367 of the MPi Workshop Manual:

[nicklouse]

 

With an AEM X series oil temp gauge, never seen mine go above 120c. If it was going to 150c, you've got some serious issues!

Thank you.  That is encouraging, but from where in the engine is the temperature information being sent ?

 

From an orifice on the drivers side of the MPi oil filter. Which is not present on other blocks.

[DeadSquare]

 

 

With an AEM X series oil temp gauge, never seen mine go above 120c. If it was going to 150c, you've got some serious issues!

Thank you.  That is encouraging, but from where in the engine is the temperature information being sent ?

 

From an orifice on the drivers side of the MPi oil filter. Which is not present on other blocks.

 

Presumably the orifice opens off the main oil gallery that feeds the three webs, so is as cool as it is likely to get.

 

Now all I have to find out from someone like Castrol, is how much the oil gets heated by being compressed as it is being squidged between the main crank journal and the bearing shells.

[gazza82]

Has anyone seen their Mini oil temperature exceed 150C ?

Why do you ask?

[DeadSquare]

 

Has anyone seen their Mini oil temperature exceed 150C ?

Why do you ask?

 

Because it is not recommended that "Belzona", aka 'plastic metal', is used if the surrounding temperature is above 150C.

[viz139]

If I remember my physics right liquid's heat up when pressurised and cool as  pressure reduces. This would suggest the hottest point is after the oil pump which is close to where the MPi sensor sits.  You can get filter mounts with sensor holes.

https://www.minispor...itting-kit.html

[DeadSquare]

If I remember my physics right liquid's heat up when pressurised and cool as  pressure reduces. This would suggest the hottest point is after the oil pump which is close to where the MPi sensor sits.  You can get filter mounts with sensor holes.

https://www.minispor...itting-kit.html

I believe that you are correct, and that the oil leaving the oil pump will have a higher temperature than when it is sucked in, but at this stage in the oil circulation, there is quite a large volume of oil to be heated.

 

Almost at once, a proportion of that oil is dumped into the sump and the remaining oil, which will cool a little as it is filtered, won't loose the heat from compression until it has passed the surface of the crankshaft journals and escapes into the sump.

 

Apart from providing lubrication to the crankshaft, the other important thing that the oil does is to remove heat from the journals where a very small volume of oil is being compressed, as a thin film, by the pressure of the crankshaft against the main bearing caps.  It is the temperature of the main bearings, being cooled by the escaping oil, that I need to know.