Cooling Problems
Turbo Mini Forums

My Mini Turbo has some cooling issues, it is of the side mount radiator type. I have had the radiator recored to a 4 row, had the bottom tank slightly largenged to hold more water, taken the thermostate out, new water pump, temperature sender, radiator cap.....and my mini still runs extremely hot to boardline overheating temparatures.... heats up mainly when i thrash it or sitting in traffic for too long.

It doesnt lose or use any water

I have taken the manual fan off the water pump and fitted an electric one to the radiator and that has made a huge difference!....but on a really hot sunny day it is still useless!

Have thought about changing to a larger front mounted radiator but there is compicated work in doing this, would need to move my intercooler, oil cooler, alternator and oil filter assembly.
Have been thinking i could do away with the mini water pump and fitting an electric water pump.
Has anyone done this? if so do they work alot beter?

Thanks, Jeremy

1975 MkIII Morris Mini 1300 Turbo, 100bhp...if only it could run long enough to drive it legally!

Your pump should be fine, and assuming that your radiator is in good condition it should be up to the job also.

Personally, I'd put the mechanical fan on as well as the electric.

You say you've removed the thermostat, have you replaced it with a blanking sleeve?

You could also try using some 'water wetter' ( http://www.redlineoil.com/products_coolant.asp )or similar product, I had good results with this.

Edited by wil_h on 31st Mar, 2006.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

Thanks Wil , i will give that water wetter stuff from redline a try if i find someone that sells it over here, sounds really interesting.

Yes i have tryed having the thermostat with the centre punched out to try and keep the same flow of water...(is that what you mean by sleeved) but it makes no difference, ive found no thermostat keeps the running temp lower for longer.

Cheers

1975 MkIII Morris Mini 1300 Turbo, 100bhp...if only it could run long enough to drive it legally!

A blanking sleeve like this is what you need

http://www.minispares.com/Product.aspx?pid=36446

there are also a couple of links to articles on the page which might be worth a read.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

Have you carried out the block mod as detailed in Vizard? This is worth doing for improved water flow round the block. Also, are you using the take off at the end of the cyl head to circulate water? As this also leads to better circulation.

I suffered from some overheating problems, traced the fault to the water pump, it had a small pressed steel impeller, as opposed a large (cast?) impellers. Changed the pump to a decent one from minispares, and alls OK.

As Tom mention, its worth carrying out Vizard’s block mod, and if my memory serves me correctly, he also talks about water pumps etc.

but mine was this bad last year and tried all the above.

but first make sure she is tuned properlyon a rolling road as this made a huge difference to mine, if the ign is to far retarded and running lean she will overheat in a instant.

also the best stat to use is a 74 deg one with out any holes in. if you remove one and even fit a blanking sleve the water will flow through the rad to quick and they will be less time for the water to cool down.

but you will need to fit anaditonal rad from your heater take off and fit to the front of the car some were, heater matrixfrom say a rover or a ford works well.

or like some fit a front rad if you have the romm

always looking for them bigger bunches of bannanas

What water pump pulley are you using is it the big 4in pulley or the std 3 1/2in pulley

the 4in pulley will slow the flow down and help cool the engine

Edited by jimmy on 31st Mar, 2006.

1293 Turbo mini

Do you have vents in the bonnet?

1275 with Back Door Turbo

I've seen the future and tbh its Pie

As has been alluded to earlier in this thread, pumping the water slower will allow it more time in the rad to cool down, however I don't buy this, as by the same token it will spend more time in the engine getting hotter.

I seem to remember that the mini water pumps are most efficient at 2000rpm so anything above this is just pointless, so either pully will work when moving, but the smaller one will be better at idle.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

yeah i know what people are saying about having more time to cool in the rad, but moving the water faster would mean that the water which would have had time to cool for longer would be replaced by hotter water directly from the engine. This would keep the head differential up and aid cooling efficiency, i would have thought. I dont buy this slow moving water thing at all, in lab testing i did on a cooling system (radiator side, ignoring the pump etc) we wanted the water moving the fastest to keep the hottest possible water closest to the cores and fins. This overall means more heat going out the rad, which means more heat loss in the engine.

You'll get more loss with the smaller pulley,but idle temperatures will certainly be better.

I've seen the future and tbh its Pie

Hey,

My water pump has the steel fins on it not the cast.....is that not ok? The steel fins are decent sized not like the cheap tawianese one i fitted to my little 1000cc run about recently.
Do you think thats the problem though?

What is the Vizard's mod to the block? how do i find out some info about that?

The heater hasnt been hooked up either, have thought it maybe compromising the water circulation around the head so i will get that sorted.....also fitting a lower rated thermostats a good idea.

Yes i not sure about fitting the larger 4inch pulley, think it would be a bad move there, have changed the one on the 1000cc to a smaller 1275gt one and also on another mini i used to have.
I have found that improves cooling.

No i dont have any scoops or vents in my bonnet, i would do it if it was absolutely nessasary.... but i like trying to keep the fact that is turbo'd concealed because i get such a thrill from suprising people when driving it !

Jeremy

Edited by j_d_jag_mini on 1st Apr, 2006.

1975 MkIII Morris Mini 1300 Turbo, 100bhp...if only it could run long enough to drive it legally!

You have all got the wrong end of the stick with the pulley size, it is not to do with flow rate (or "speed" if you prefer).

The larger pulley was fitted to A+ engines to reduce the speed of the pump, this was to reduce the possibility of cavitation at high speed.