21 replies to this topic

[croc7]

Just returned from a 600 mile drive this past weekend that included climbs over two mountain passes, one at 4200', the other 5500'.  Those long climbs in unusually warm weather were a challenge to the cooling system.  If memory serves, one of the tricks to improve cooling was drill 4 to 6 1/8" holes around the perimeter of the 'stat.  Can't remember the reason for it.  Seems that doing so would partially defeat the function, allowing water flow regardless of the opening/closing of the 'stat.  Accuracy of the water temp gauge verified with laser temp so coolant temps were hovering close to 212 degrees.  Thoughts?

[nicklouse]

Holes in the stat do not improve cooling they just make getting up to temp take longer.

[nicklouse]

212F is only 100C not a problem.

[Aria Aradhea]

Just returned from a 600 mile drive this past weekend that included climbs over two mountain passes, one at 4200', the other 5500'. Those long climbs in unusually warm weather were a challenge to the cooling system. If memory serves, one of the tricks to improve cooling was drill 4 to 6 1/8" holes around the perimeter of the 'stat. Can't remember the reason for it. Seems that doing so would partially defeat the function, allowing water flow regardless of the opening/closing of the 'stat. Accuracy of the water temp gauge verified with laser temp so coolant temps were hovering close to 212 degrees. Thoughts?

If I'm not mistaken, drilling holes on the thermostat is done if you don't have the bypass hose so that some water still circulate around the engine.

[nicklouse]

 

Just returned from a 600 mile drive this past weekend that included climbs over two mountain passes, one at 4200', the other 5500'. Those long climbs in unusually warm weather were a challenge to the cooling system. If memory serves, one of the tricks to improve cooling was drill 4 to 6 1/8" holes around the perimeter of the 'stat. Can't remember the reason for it. Seems that doing so would partially defeat the function, allowing water flow regardless of the opening/closing of the 'stat. Accuracy of the water temp gauge verified with laser temp so coolant temps were hovering close to 212 degrees. Thoughts?

If I'm not mistaken, drilling holes on the thermostat is done if you don't have the bypass hose so that some water still circulate around the engine.

 

And is not actually needed. 

[Aria Aradhea]

 

 

Just returned from a 600 mile drive this past weekend that included climbs over two mountain passes, one at 4200', the other 5500'. Those long climbs in unusually warm weather were a challenge to the cooling system. If memory serves, one of the tricks to improve cooling was drill 4 to 6 1/8" holes around the perimeter of the 'stat. Can't remember the reason for it. Seems that doing so would partially defeat the function, allowing water flow regardless of the opening/closing of the 'stat. Accuracy of the water temp gauge verified with laser temp so coolant temps were hovering close to 212 degrees. Thoughts?

If I'm not mistaken, drilling holes on the thermostat is done if you don't have the bypass hose so that some water still circulate around the engine.

 

And is not actually needed. 

 

Even without the heater connected?

[Spider]

J, what Radiator and Fan are you running ?

Is the tune on the engine spot on (as in Carb needle and dissy curve) ?

 

What coolant are you using ?

 

I wouldn't be alarmed at 212F (100 for us EU followers), but doesn't leave much head room.

 

 

 

 

Just returned from a 600 mile drive this past weekend that included climbs over two mountain passes, one at 4200', the other 5500'. Those long climbs in unusually warm weather were a challenge to the cooling system. If memory serves, one of the tricks to improve cooling was drill 4 to 6 1/8" holes around the perimeter of the 'stat. Can't remember the reason for it. Seems that doing so would partially defeat the function, allowing water flow regardless of the opening/closing of the 'stat. Accuracy of the water temp gauge verified with laser temp so coolant temps were hovering close to 212 degrees. Thoughts?

If I'm not mistaken, drilling holes on the thermostat is done if you don't have the bypass hose so that some water still circulate around the engine.

 

And is not actually needed. 

 

Even without the heater connected?

 

 

I've been banking off the By-pass hose on all my Minis and Mokes going back 35+ years and goodness know how many Miles / KM. Some of these have heaters, some not. Those with heaters all have valves to shut off flow the the heaters in any case. I've never drilled the Thermostat and never had any issues from running this way. The only down side I have found is it takes a little longer to fill and bleed the air out of them. I like to let the Thermostat do it's job. Even when it's closed completely, the warm coolant will always naturally rise to it anyway.

[Ethel]

I confess I've drilled 'em, but it's just been from received wisdom. If you look where the temperature sensor is situated, the thermostat is not going to be any colder for the lack of a hole or two. The other argument is better temperature distribution in the head, but using the heater take off on the other end, or dry decking, would be a better solution. Besides, with an 88^o stat & a system that'll boil at around 120^o how much difference could there really be?

 

Do SU's do altitude correction  ???

 

 

... I think they might.

[Spider]

Do SU's do altitude correction  ???

 

Good point and actually, no they don't.
 

[croc7]

J, what Radiator and Fan are you running ?

Is the tune on the engine spot on (as in Carb needle and dissy curve) ?

 

What coolant are you using ?

 

I wouldn't be alarmed at 212F (100 for us EU followers), but doesn't leave much head room.

 

 

 

 

Just returned from a 600 mile drive this past weekend that included climbs over two mountain passes, one at 4200', the other 5500'. Those long climbs in unusually warm weather were a challenge to the cooling system. If memory serves, one of the tricks to improve cooling was drill 4 to 6 1/8" holes around the perimeter of the 'stat. Can't remember the reason for it. Seems that doing so would partially defeat the function, allowing water flow regardless of the opening/closing of the 'stat. Accuracy of the water temp gauge verified with laser temp so coolant temps were hovering close to 212 degrees. Thoughts?

If I'm not mistaken, drilling holes on the thermostat is done if you don't have the bypass hose so that some water still circulate around the engine.

 

And is not actually needed. 

 

Even without the heater connected?

 

 

I've been banking off the By-pass hose on all my Minis and Mokes going back 35+ years and goodness know how many Miles / KM. Some of these have heaters, some not. Those with heaters all have valves to shut off flow the the heaters in any case. I've never drilled the Thermostat and never had any issues from running this way. The only down side I have found is it takes a little longer to fill and bleed the air out of them. I like to let the Thermostat do it's job. Even when it's closed completely, the warm coolant will always naturally rise to it anyway.

C, I'm running a four blade metal fan with a three core radiator, 194 degree 'stat.  Probably should install one rated at 180.  The engine has been bored out to 1360, using a BDK needle with the AFR adjusted on the rich side, low 13's at idle and low 14's at cruise.  Distributor has been modified by Ac Dodd and timed in a 10 degrees BTDC, vacuum advance disconnected. 

 

The cooling system on a mini has always been a puzzlement to me.  Blowing hot air from the engine compartment through the radiator seems backwards.  

[nicklouse]

 

J, what Radiator and Fan are you running ?

Is the tune on the engine spot on (as in Carb needle and dissy curve) ?

 

What coolant are you using ?

 

I wouldn't be alarmed at 212F (100 for us EU followers), but doesn't leave much head room.

 

 

 

 

Just returned from a 600 mile drive this past weekend that included climbs over two mountain passes, one at 4200', the other 5500'. Those long climbs in unusually warm weather were a challenge to the cooling system. If memory serves, one of the tricks to improve cooling was drill 4 to 6 1/8" holes around the perimeter of the 'stat. Can't remember the reason for it. Seems that doing so would partially defeat the function, allowing water flow regardless of the opening/closing of the 'stat. Accuracy of the water temp gauge verified with laser temp so coolant temps were hovering close to 212 degrees. Thoughts?

If I'm not mistaken, drilling holes on the thermostat is done if you don't have the bypass hose so that some water still circulate around the engine.

 

And is not actually needed. 

 

Even without the heater connected?

 

 

I've been banking off the By-pass hose on all my Minis and Mokes going back 35+ years and goodness know how many Miles / KM. Some of these have heaters, some not. Those with heaters all have valves to shut off flow the the heaters in any case. I've never drilled the Thermostat and never had any issues from running this way. The only down side I have found is it takes a little longer to fill and bleed the air out of them. I like to let the Thermostat do it's job. Even when it's closed completely, the warm coolant will always naturally rise to it anyway.

C, I'm running a four blade metal fan with a three core radiator, 194 degree 'stat.  Probably should install one rated at 180.  The engine has been bored out to 1360, using a BDK needle with the AFR adjusted on the rich side, low 13's at idle and low 14's at cruise.  Distributor has been modified by Ac Dodd and timed in a 10 degrees BTDC, vacuum advance disconnected. 

 

The cooling system on a mini has always been a puzzlement to me.  Blowing hot air from the engine compartment through the radiator seems backwards.  

 

It can’t move it any other way and get rid of it. Hence the mechanically driven fan. And it is not really hot air as it is still coming from the front of the car. The only issue is in stationary traffic. Hence why the last side mount rad cars had the electric helper fans in addition to the mechanically driven fan.

 

back to yours. The 4 blade fan ain’t up to much. The standard plastic fan is better. But the export 6 blade is said to shift more air. I found the standard fan fine.

[Aria Aradhea]

Do you have the electric fan fitted? For my usage, I have a JDM-spec Mini with a 1293cc with a 6-blade fan, standard radiator, and the electric fan. I disconnected my heater and run without a thermostat but fitted the thermostat blanking sleeve. Where I live, ambient temperature is never below 25°c and road temperature is on average around 30-35°c and I always turn on my air conditioning on the road. So, basically, a hillclimb situation all the time... 😄

The 6-blade fan combined with the electric fan is effective enough to keep the temp gauge around the halfway mark (probably around 88-95°c) and when in traffic it went a little above the halfway (so around 100-ish°c same as yours). Bonus heat if it was a scorching day out.

So, I'm going to say yours is fine. You can fit the standard 11-blade fan for more air flow and it's a bit quieter too.

[croc7]

I confess I've drilled 'em, but it's just been from received wisdom. If you look where the temperature sensor is situated, the thermostat is not going to be any colder for the lack of a hole or two. The other argument is better temperature distribution in the head, but using the heater take off on the other end, or dry decking, would be a better solution. Besides, with an 88^o stat & a system that'll boil at around 120^o how much difference could there really be?

Do SU's do altitude correction ???


... I think they might.

I’ve heard the term but don’t know what ‘dry decking’ is.

[nicklouse]

 

I confess I've drilled 'em, but it's just been from received wisdom. If you look where the temperature sensor is situated, the thermostat is not going to be any colder for the lack of a hole or two. The other argument is better temperature distribution in the head, but using the heater take off on the other end, or dry decking, would be a better solution. Besides, with an 88^o stat & a system that'll boil at around 120^o how much difference could there really be?

Do SU's do altitude correction ???


... I think they might.

I’ve heard the term but don’t know what ‘dry decking’ is.

 

Blocking the waterways between the head and the block and machining the head so you can then connect a hose between the clutch end of the block and head. So the water flows through the block and out and then back in to the head before going to the rad.

 

it does nothing to reduce the operating temp of the engine. All it does is even out the temp across the head.

[sonscar]

The thermostat has no effect on the water temperature,it only affects how hot it gets until it opens.Once the coolant is above the opening temp then that is it.Fitting a cooler stat will not make the engine run cooler.Or this is just my understanding.Steve..