Discussion
My mini is running a 103hp 1330cc engine, with oil cooler, 4 core rad and electric fan (original plastic fan removed).
In normal driving it's fine, but if used enthusiastically for prolonged periods (over 45 minutes), or cruising on the motorway (at 4,000rpm), it's almost at the point of overheating (steaming / water loss from the rad cap).
I only use the car now for an occasional weekend blast (up to 2 hours) and occasionally moving it between Leicester and London, which means that it's a problem most of the time.
What's the solution?
One of the new type 2 core radiators (or the v expensive ali ones)
Water wetter / temperature reducing agent
front mounted rad
It's in a 1275GT so space isn't as much of a problem as a pretty mini!
Any help much appreciated.
James
In normal driving it's fine, but if used enthusiastically for prolonged periods (over 45 minutes), or cruising on the motorway (at 4,000rpm), it's almost at the point of overheating (steaming / water loss from the rad cap).
I only use the car now for an occasional weekend blast (up to 2 hours) and occasionally moving it between Leicester and London, which means that it's a problem most of the time.
What's the solution?
One of the new type 2 core radiators (or the v expensive ali ones)
Water wetter / temperature reducing agent
front mounted rad
It's in a 1275GT so space isn't as much of a problem as a pretty mini!
Any help much appreciated.
James
The problem is that the electric fan is totally insufficient to cool it properly.
To keep such a powerful engine cool you need a 6-blade fan PLUS an electric fan.
Once they start to get hot it really is hard to cool them down again.
I don't think I've ever come across a Mini with a side-mounted rad that didn't have a belt-driven fan in the usual place.
Whatever you do, don't 'cook' that lovely engine.
You can get a 6-blade fan from Mini Spares off-the-shelf. It's what all the competition Mini drivers use.
To keep such a powerful engine cool you need a 6-blade fan PLUS an electric fan.
Once they start to get hot it really is hard to cool them down again.
I don't think I've ever come across a Mini with a side-mounted rad that didn't have a belt-driven fan in the usual place.
Whatever you do, don't 'cook' that lovely engine.
You can get a 6-blade fan from Mini Spares off-the-shelf. It's what all the competition Mini drivers use.
The car has run for 25,000 miles without using any oil or needing a head gasket replaced (other than the time my k&n fell apart and the retaining bolt made its way in to the head!).
Due to the build spec (276 cam, 1.5 roller rockers, stage 3 head close ratio box etc), it spends most of its time 4,000-6,200 rpm.
My understanding is that any fan is redundant above about 50mph and it actually hinders the performance of the radiator. The electric fan is about 12" diameter kenlowe mounted on a home made bracket holding it about 1/4" from the outside of the radiator, not one of the small types put on later minis to help cooling at low speeds.
The car never overheats in heavy traffic and the fan cuts in at 88 degrees I think.
It's also nice to hear the A series without a noisy belt driven fan on all the time (and revs more cleanly too). I don't really want to revert to a pump driven fan and don't think it will solve the problem.
Due to the build spec (276 cam, 1.5 roller rockers, stage 3 head close ratio box etc), it spends most of its time 4,000-6,200 rpm.
My understanding is that any fan is redundant above about 50mph and it actually hinders the performance of the radiator. The electric fan is about 12" diameter kenlowe mounted on a home made bracket holding it about 1/4" from the outside of the radiator, not one of the small types put on later minis to help cooling at low speeds.
The car never overheats in heavy traffic and the fan cuts in at 88 degrees I think.
It's also nice to hear the A series without a noisy belt driven fan on all the time (and revs more cleanly too). I don't really want to revert to a pump driven fan and don't think it will solve the problem.
Silly question...but is the electric fan pulling air the right way?
At speed in a Mini there's a slight vacuum in the wheel well. The fan (whether original belt-driven or electric aftermarket) must move air FROM the engine bay into the NS wheelwell to do any cooling. If your electric fan is trying to push air through the rad the other ay, yes it would work fine in traffic, but at speed it would not be able to keep up - or worse, stall the natural airflow through the rad. Which would result in overheating.
If that's all OK - you simply need more rad area / a better rad.
At speed in a Mini there's a slight vacuum in the wheel well. The fan (whether original belt-driven or electric aftermarket) must move air FROM the engine bay into the NS wheelwell to do any cooling. If your electric fan is trying to push air through the rad the other ay, yes it would work fine in traffic, but at speed it would not be able to keep up - or worse, stall the natural airflow through the rad. Which would result in overheating.
If that's all OK - you simply need more rad area / a better rad.
Huff said:
Silly question...but is the electric fan pulling air the right way?
At speed in a Mini there's a slight vacuum in the wheel well. The fan (whether original belt-driven or electric aftermarket) must move air FROM the engine bay into the NS wheelwell to do any cooling. If your electric fan is trying to push air through the rad the other ay, yes it would work fine in traffic, but at speed it would not be able to keep up - or worse, stall the natural airflow through the rad. Which would result in overheating.
If that's all OK - you simply need more rad area / a better rad.
It's actually a good question as I can't remember the answer, but it was about 6 years ago when I wired it up (it's a shame but I don't have the time to use it much these days).At speed in a Mini there's a slight vacuum in the wheel well. The fan (whether original belt-driven or electric aftermarket) must move air FROM the engine bay into the NS wheelwell to do any cooling. If your electric fan is trying to push air through the rad the other ay, yes it would work fine in traffic, but at speed it would not be able to keep up - or worse, stall the natural airflow through the rad. Which would result in overheating.
If that's all OK - you simply need more rad area / a better rad.
I will check this weekend.
Thanks
I run my mini with 110bhp+ at the fly wheel. It runs a standerd 4 blade fan with an mini spairs high performance rad. The thermostate has been drilled and the by pass pipe blocked off. There is a good antifrez/coolant mix. At this time the car has never over heated.
I have seen a lot of diffrent idears for futher cooling, the othere one I have done in the past is run a metro rad at the front of the car with a mondayo dizzy cap. I found it hard to keep the tempriter up.
In your case if the fan direction dosent do it, I would try changing the rad for an up-grade one(I dont remeber them beeing that much money). It can only help.
I have seen a lot of diffrent idears for futher cooling, the othere one I have done in the past is run a metro rad at the front of the car with a mondayo dizzy cap. I found it hard to keep the tempriter up.
In your case if the fan direction dosent do it, I would try changing the rad for an up-grade one(I dont remeber them beeing that much money). It can only help.
As you've got a 1275 GT use the front space and fit a front mounted Rad. A Mk1 Metro rad (thick core) will provide you with all the cooling you could wish for. Fit a Midget dizzy cap for extra clearance and install your Kenlowe for the times the car is stuck in traffic.
This is my install on my roundnose racer - No electric fan as it doesn't sit in traffic.
This is my install on my roundnose racer - No electric fan as it doesn't sit in traffic.
I have 1430 oselli built cooper with a 13" ford cargo truck fan under the inner wing with small wents in it also without belt driven fan with a 13gt 4 core rad it keeps it down but then needed larger alternator relays etc can be a nitemare was for us at the start fan runs all the time found this to be the best but souds like a massive vacum cleaner on tick over.
the fox
the fox
Gassing Station | Classic Minis | Top of Page | What's New | My Stuff