31 replies to this topic

[Cerberus]

 

I'd suggest trying to find what the underlying problem is and fix that.

 

Pretty sure a standard mini should be able to cope with anything here in the UK, even the current heatwave,

 

 

I think mine needs a flush as it did go just over the normal mark (needle thickness over) the other day, putting the heater on (just opening the tap) dropped it back down again (didn't get any hotter in the car as it was already too hot, ).

 

My car has the standard rover electric fan, but it's not been working since I've had the car, tried to get it working yesterday by cleaning up the contacts, just got to see if it makes any difference the next time I go out (or if it even works, might end up just having to mod it to a switch inside if the otter switch is broken).

 

 

Put a link wire across the two spades and see if it fires up, if it does then so long as the switch is OK, it will run....if the switch is not OK, why not just replace it so you don't have to worry about manual switches.

I'm out of the dark ages now - all the vehicles I drive can look after their own cooling without my help

 

 

The fan works, did jumped the connections the other day to check it. 

 

Cleaned up the spades while they were off, and now I'm just waiting to run it up to temp to see if it works yet.  If it doesn't, I'll probably just put a switch in, as I can't be bothered to replace the otter switch, too much hassle,

The car only ever goes over the normal mark on the very hottest of days regardless of what it's doing, so won't need the electric fan most of the time anyway.

[Hunter2]

This conversation is very similar to some often repeated in North America...

My Mate's Cooper S build in Australia was very much aftermarket - BL Australia stopped making Minis there in 1978. So his Mini build was a one-off. I mentioned his one incident on a hot day in bumper to bumper weekend traffic because he had a thermostat to activate the extra, electrical cooling fan. His problem - 2/3rds of the way along a 70 day drive around OZ a connection came loose...on a very hot day...and his coolant temps spiked up rapidly.

My Mini was originally a 1980 (last year Minis were exported to Canada) Air Injected (smogged) 998 exported to Canada. When I learned from long trips into the US southwest that extra cooling measures were needed, I installed them into the 1380 build. This included a custom recore of the 998 radiator, oil cooler & extra rad and the deliberate bypassing of an automatic electrical component - thermostat & its connections - in favor of a hard wired switch on the dash. Simpler, reduced possibility of electrical fault, can be kicked in when and if needed.

I will grant that someone buying a used Japanese spec Mini with Air Conditioning (they are imported from Japan by several parties here and sold into the domestic market) will not need to be paying attention to cooling the engine since "it's cool inside the Mini greenhouse" until there's a problem and won't catch up to reality (if at all) until after the problem occurs.

All I can say after many years experience...build the simplest set of purposeful components and, as Issigonis might have noted, "don't be so comfortable that you don't notice what's going on".

[daenesh]

Hunter2 knows what hes talking about.. i have to agree with you on that.. i live in Malaysia and our day temperatures can reach 35 degrees Celsius and i consider that to be a hot day.. obviously we use Air conditioning units here as i supposed you do to in Australia rather than using a heater.. but even since i fixed the AC unit in my 998 clubby ive always notice very high temperatures as the load on the engine is immense..

 

I've fitted an Auxiliary fan which has a manual switch and its usually running non-stop to no avail.. i still find my temperatures in the 90-100 degrees Celsius bracket depending on how fast im going..usually in this case 90 degrees if im going 80-90km/h constant and 100 degrees if i go 80-90km/h and then get stuck in traffic.. my Aux fan is a 80 watt 5 blade which is really good and my thermostat a 88 degree one if im not mistaken but i have made bypass holes around as per david vizards book.. unfortunately doesn't make a difference..

 

my engine is rebuilt and was clean down to the bone and the rad was serviced and pressure tested.. after trying so hard to figure it out and was not successful i just gave up.. maybe one day ill get either and aluminum radiator or fit a second radiator.. which is weird considering its a standard 998cc with 1098 cam..  

Edited by daenesh, 26 July 2013 - 06:56 AM.

[phil hill]

The "old skool" way of adding more cooling capacity was to add a heater matrix up front.  Now the early MK1 style matrix's (matri ??) lend themselves well to this, being "fully enclosed" if you see what I mean, but the later "open frame" ones don't mount so well and need some ingenuity to mount.

 

This got me thinking about rads fitted to modern watercooled motorbikes and scooters.  They seem to be the right kind of size, plentiful and reasonably cheap.  Anyone tried one, and if so what bike rad did you try ??

 

Phil.

[maccers]

I see on page 39 in this months Mini World there is a white Van feature, and has the metal rad cowl cut at the front, I can only imagine to let in more air. The engine fitted according to the article is a 998cc.

 

Would this allow more cooling?

[Captain Mainwaring]

This conversation is very similar to some often repeated in North America...

My Mate's Cooper S build in Australia was very much aftermarket - BL Australia stopped making Minis there in 1978. So his Mini build was a one-off. I mentioned his one incident on a hot day in bumper to bumper weekend traffic because he had a thermostat to activate the extra, electrical cooling fan. His problem - 2/3rds of the way along a 70 day drive around OZ a connection came loose...on a very hot day...and his coolant temps spiked up rapidly.

My Mini was originally a 1980 (last year Minis were exported to Canada) Air Injected (smogged) 998 exported to Canada. When I learned from long trips into the US southwest that extra cooling measures were needed, I installed them into the 1380 build. This included a custom recore of the 998 radiator, oil cooler & extra rad and the deliberate bypassing of an automatic electrical component - thermostat & its connections - in favor of a hard wired switch on the dash. Simpler, reduced possibility of electrical fault, can be kicked in when and if needed.

I will grant that someone buying a used Japanese spec Mini with Air Conditioning (they are imported from Japan by several parties here and sold into the domestic market) will not need to be paying attention to cooling the engine since "it's cool inside the Mini greenhouse" until there's a problem and won't catch up to reality (if at all) until after the problem occurs.

All I can say after many years experience...build the simplest set of purposeful components and, as Issigonis might have noted, "don't be so comfortable that you don't notice what's going on".

 

If a thermostat can fail, so can a switch, if a wire can drop off the stat, it can drop off the switch. As someone who designs control systems for safety critical applications, I'm well aware that if something can fail, it will, but to make a real mess of something you need a human.

If there was a known quality issue with the stat and nothing was available, then I may consider wiring a switch in parallel, but certainly not as a replacement.

 

My wife enjoys driving the Mini, but there is no way I'd leave the possibility of an issue arising because she forgot to turn the fan on, or turned it off for some reason.

 

 

Each to their own of course, but I built the car to be reliable in the conditions I operate it - both the fans work automatically and the car controls itself as it should. I think ideally you need to fix the root cause of any overheating issue.

[Captain Mainwaring]

I see on page 39 in this months Mini World there is a white Van feature, and has the metal rad cowl cut at the front, I can only imagine to let in more air. The engine fitted according to the article is a 998cc.

 

Would this allow more cooling?

 

to be honest anything over the OEM arrangement would be a bonus. At some point I'll stick a pitot and mag gauge in the inner wing and gun the thing and see just what airflows are about. At best the OEM arrangement is adequate rather than inspiring.

[daenesh]

on a clubman theres plenty of air coming from the grill. hahaha

[maccers]

Front mounted rad has got to be the best way. I dont have a dizzy but alternator in the way a bit. Could make something up.

[Dan]

 matrix's (matri ??)

 

  Matrices.

 

 

on a clubman theres plenty of air coming from the grill. hahaha

 

 People say that a lot but I'm pretty sure the open area of a Clubman grille is actually smaller than that of a regular Mini.

 

 I would think cutting away part of the cowling would reduce the effective flow, ducted fans work far better than open ones.  As for auxiliary rads made from heaters, the matrix is pretty fragile.  The ERA had an auxiliary rad that was the same size as a heater matrix but built as per a proper rad and so a bit tougher.  These were still available until a couple of years back, there may be old stock kicking about somewhere still.

 

[Hunter2]

I use a GM pickup truck heater core as the auxiliary radiator in my round nose 1980 Mini sedan. It slides into a frame held by one bolt in the top of the slam panel...can be easily lifted out and hung over the wing for servicing at the clutch end. But be careful, MkI Minis I've seen here need to use a thinner auxiliary rad as the space between the power unit and grill is reduced.

Took a new GM item to Australia in luggage and plumbed it in behind the 1973 Clubman Window Van grill...super easy (as are oil filter changes vs. the round nose Minis). This followed new radiator, water pump, hoses, belt, thermostat installed for me by the seller, as the Mini was prepared for 30,000 kilometres/17,000 miles circling Australia.

The Clubman nose allows a wider variety of possible auxiliary rads to be used. Lots to choose from in the catalogues at the parts store.

In 45C heat crossing the north in Western Australia, the Van was just fine...while the wife sweltered under a wet towel to cool.

And like oil coolers, it can be readily blocked off when not needed.

[Tahiti Joe]

Find all this talk about cooling kinda funny, as good as all these auxiliary rads and different cooling modifications are, a regular installation of a system with readily available components will work very well.

I'm using a Minispares 2 core radiator, along with a 6 blade metal fan and the smaller water pump pulley. I have a wing mounted electric fan but it is currently not connected. I'm typing this from Southern France, today it has been 37 degrees, the car has never got worryingly hot even in slow moving traffic. 2 days ago I was stuck in traffic in Lyon for over an hour in 35 degree heat, again the temp gauge went up to just over half, and stayed there. Heater was off too.

[Captain Mainwaring]

Find all this talk about cooling kinda funny, as good as all these auxiliary rads and different cooling modifications are, a regular installation of a system with readily available components will work very well.

I'm using a Minispares 2 core radiator, along with a 6 blade metal fan and the smaller water pump pulley. I have a wing mounted electric fan but it is currently not connected. I'm typing this from Southern France, today it has been 37 degrees, the car has never got worryingly hot even in slow moving traffic. 2 days ago I was stuck in traffic in Lyon for over an hour in 35 degree heat, again the temp gauge went up to just over half, and stayed there. Heater was off too.

 

I also think it can be achieved too. What I get puzzled about is the 120 HP monsters that get created, but what happens to the cooling systems?

 

We know that pretty much a fixed proportion of engine power (for various outputs on a given block and head size) goes to the cooling system - so by definition a standard mini @39 bhp needs 1/3 the cooling capacity of these 120 bhp monsters. so really it should be simple to take these guys components and bolt them into a standard car and see the gauge sitting well below N at all times.....well either that or these things can make 120 bhp for 5 seconds or so, then blow all their water out....maybe the second scenario is closer to the truth....

 

What we can say is that from fan affinity laws and what we know about heat transfer is that something must be 3 times bigger than the standard setup, just to keep up.

Edited by Captain Mainwaring, 27 July 2013 - 04:33 AM.

[daenesh]

i find it hilarious.. because i notice that people who use standard 1275 engines (as compared to 998s) have less heating problems due to reduced load achieved by a higher cc.. so obviously with a well maintained cooling system it can be achieved and especially if you live in a cold country or use a heater matrix..which essentially blows the hot radiator air into the car.. which is turn cools a little bit at the same time..

 

try using a 998cc and fitting an A/C unit and you will see the load on the engine.. even with a well maintained engine and cooling system there will be notice of higher temperatures especially in humid heats of 35-37 degrees Celsius.. so i would say it depends on conditions and the setup up of your car as compared to every mini being the same.. the side mounted radiator doesn't promote extreme cooling like front mounted radiators do..

Edited by daenesh, 27 July 2013 - 05:22 PM.

[phil hill]

 

Find all this talk about cooling kinda funny, as good as all these auxiliary rads and different cooling modifications are, a regular installation of a system with readily available components will work very well.

I'm using a Minispares 2 core radiator, along with a 6 blade metal fan and the smaller water pump pulley. I have a wing mounted electric fan but it is currently not connected. I'm typing this from Southern France, today it has been 37 degrees, the car has never got worryingly hot even in slow moving traffic. 2 days ago I was stuck in traffic in Lyon for over an hour in 35 degree heat, again the temp gauge went up to just over half, and stayed there. Heater was off too.

 

I also think it can be achieved too. What I get puzzled about is the 120 HP monsters that get created, but what happens to the cooling systems?

 

We know that pretty much a fixed proportion of engine power (for various outputs on a given block and head size) goes to the cooling system - so by definition a standard mini @39 bhp needs 1/3 the cooling capacity of these 120 bhp monsters. so really it should be simple to take these guys components and bolt them into a standard car and see the gauge sitting well below N at all times.....well either that or these things can make 120 bhp for 5 seconds or so, then blow all their water out....maybe the second scenario is closer to the truth....

 

What we can say is that from fan affinity laws and what we know about heat transfer is that something must be 3 times bigger than the standard setup, just to keep up.

 

Yep, well that's kinda my situation.  My 1293 track car isn't quite 120hp, more like 100hp, cast impeller water pump, 2 core rad, large pump pulley, mech fan and electric fan to boot.   It doesn't blow it's water outta the overflow and it's held it's headgasket all the way to 110 deg C (before the electric fan was fitted).  It's ok on the move, but gets hot when stationary, I guess because of slow pump/fan speed caused by large pump pulley.  The electric fan has brought things back under control when in traffic, but on a hot trackday ??  Hence the questions about auxillary rads !!  

 

Phil.