Classic Mini - Summer Cooling Guide

[@classicminidiy]

Great info from another commenter that I wanted to make sure got pinned here. My electrical diagram was focused on explaining the way relays work and I completely forgot to add details about adding a fuse to the circuit which is definetly required to protect your fan and your minis electrical system. Thank you very much Phil Jones!!

[@philjones6025]

No problem. Having worked with the great Sir Alex I, back in the early 80's in the Longbridge prototype build shop, UK. I would hate any of there scarce vehicles coming to any harm. Almost every other car on the roads in the UK used to be one of the original Minis (ADO 20), now if you do see one it turns heads!!, Keep up the great work Classic Mini DIY, we need to keep as many of them on the road as possible.

[@michaelgough9256]

Hey mate love your Vids. Where do you find that specific fan?

[@velocity800]

I had that kind of fan for about 3yrs already, still works like new

[@superuggero]

You have the power of reading into my future. Like for the radius arm refurbish, I was thinking about that one week before. Now, I was going to choose an electrical fan and you made the video ahahahah

[@classicminidiy]

🔮 I have a special Italian crystal ball that lets me see into the future of your car specifically. :-)

[@kevinmoody4491]

Thanks

[@classicminidiy]

Thank you for the contribution! Glad this video was helpful. :-)

[@WildBilly91]

Amen to the auxiliary fan !

[@zachpetersen2896]

you can also add a smaller 7 inch puller fan to the backside of the heater core......granted its going to be larger, but it's great to have when you're stopped also.....I usually switch the wheel fan on along with the heater and the front rad fan. Keeps it from climbing past neutral when sitting in our lovely interstate parking lot called I-35. I'll send you some photos of it in an email. Not as tidy as yours looks, but it keeps the engine cool.

[@classicminidiy]

Yeah I might add the smaller fan to the heater core and have that run on a thermostat switch, that way it can help keep the car cool automatically and have the large electric fan as a big dog backup so to speak.

[@zachpetersen2896]

@@classicminidiy That's pretty much what I do. I would be going through head gaskets all summer long if I didn't install it.

[@darryl3392]

Mmm Banana 🍌 I had a puller fan setup on my mini with a oven temp sensor (eBay) with a gas filled metal probe thing from one of those mini ovens. The probe was pushed through the core and an old rotary dail so you could set the temp and it would switch on and off only when extra cooling was required. Just got to remember to put coils into the sensor leads so the vibrations from the car doesn’t snap the lead and hide it up in the wheel well

[@classicminidiy]

That's a good idea, I really considered having mine temperature controlled and might still add that in the future but for now I wanted to get it on the car and running so that I can keep driving the mini in the short term.

[@darryl3392]

@@classicminidiythey are dirt cheap around $10 AUD delivered from china on fleaBay or around $30-50 sourced locally. Ebay: "Electric Oven 30-110 Celsius N.C Temperature Capillary Thermostat w 43mm Probe". used in conjunction with a relay to change it to N.O contacts and that way it works with the 12DC as the Thermostat is made for AC so you don't want to be pulling large DC currents through it. also protecting the capillary lead you can sleave it with some clear PVC hose that way if you end up with a longer probe lead you can cable tie it off. you can then place the probe at the top or bottom of the radiator and dial in the temp setting that's right for you based off what you dash temp displayed. pull off the knob once you have it set so its harder to turn on its own and away you go with the only thing to do is check it every summer so ensure the capillary hasn't broken due to the engine vibrations. I had this setup on my supercharged 1100 in Australia that loved to over heat in summer due to the excessive corrosion in the water passages. haven't used it with the fresh engine this summer as it didn't need it.

[@velocity800]

Yup i did that, you should buy the 9inches auxillary fan. Perfect fit

[@classicminidiy]

The 10 inch fan covered more of the opening so I opted for a bit larger one to move more air.

[@RakTheGoose]

I installed a fletcher racing 4 core radiator and mine cools perfectly in Dubai summers

[@classicminidiy]

That's awesome! I really would love to put a fletcher racing rad in mine however with that fixed shroud on the mk1 body it doesnt fit. :-(

[@tonysiebs3426]

Hey bro I just put this same fan u have on my mini because it's very hot sometimes in the Caribbean where I live and it helped it a 💯% better with cooling the engine

[@tonysiebs3426]

Thanks bro u always have great ideas at mind for the mini's

[@classicminidiy]

Oh man I bet it gets really warm down there. Thanks for the kind words!

[@minimonte1]

Im surprised you didnt simply cover changing the main fan to the 6 bladed metal fan. This one is much more efficient but is also a bit more noisy which is why the were not fitted as standard except for mini markets in hot places. In the mini suppliers they are even referred to as 'export fan'.

[@classicminidiy]

There has been a good bit of discussion and testing between the various different fans out there. The plastic 11 blade fan actually is the most efficient at moving air volume and cooling on these minis, and it's the least additional load on the engine when it's spinning.

[@fillrobs7726]

What's the difference between wiring to the relay and using an in line fuse? Also where did you get the positive feed from in the loom? Direct from alternator or starter motor or did you run a wire back to the fuse box and if so how did you do that (splice cable or double spade)? Great vid btw😁

[@timsminigarage]

Fans use a fair amount of power so you don’t want your other circuits getting overloaded. Using a relay means you can get positive power direct (eg from the starter solenoid) and then switch it using the relay. You’d also want a fuse fitted to the power circuit. If you search for “fan relay diagram” on google you’ll find plenty of examples

[@alistairb2980]

What about cooling inside the car? Must be pretty sweaty in the middle of summer...

[@zachpetersen2896]

We roll the windows down here in the South and pray that we don't get caught up in a traffic jam......otherwise we just sit and sweat.....lol

[@classicminidiy]

Lol "cooling inside the car".....

[@shriramvenu]

add a 12v electric fan to the accessory line and fit a switch. unless you have a mini with AC, traffic jams are torture otherwise

[@barnbuilds25]

Now its a jdm mini because you used zip ties hahah

[@classicminidiy]

#jdmlife

[@velocity800]

Hmm , south?? But you dont seem to speak like southern guy

[@classicminidiy]

I live in the south but I really don't consider myself southern. I was born in Florida then moved to NC when I was 9.

[@patrickf6553]

I love that you actually used zip ties to keep it in. They always have such a bad rep but honestly, they're removable, affordable, and don't require any drilling or cutting. Only real downside is that they look cheap but eh.

[@classicminidiy]

If it was super visible it’d be one thing but realistically this is in a wheel well. Hidden away. No need to be super fancy and rivnuted in or something. Zip ties are jussstttt fine. 😎

[@zaiphert]

Is the small radiator, installed at the front next to the grille, to help the engine cool down? How did you do this installation? Where does the tube to the back of the engine connect?

[@FaiscaaaH]

Hello mate I have one issue, maybe you can help me out, my radiator keeps expelling water from the his cap. I have changed it, bought a new already and it keeps happening.

[@pauloconnor7951]

Mini fan PUSHES air through the radiator.

[@classicminidiy]

Semantic difference. Pulls air from the front of the car and pushes it through a d out the inner wing.

[@stevenclarke5606]

I watched an episode of wheeler dealers , and Edd used a waterless coolant ( on an MGB GT , I think) benefits are , never needs to be replaced and able to transfer more heat whilst running cooler.

[@brummierabbitman9637]

Wouldn’t the fan get ruined by mud or water?

[@classicminidiy]

Yeah but it doesn't matter, its a waterproof automotive fan made for this type of application. When you wash your car and you're spraying the wheel wells out, its gonna get clean.

[@deathstar51]

I have cut a hole behind the radiator and have mounted the fan directly behind the radiator. I’m my situation is it better to mount the fan in the wheel well or inside the bay in front of the radiator?

[@deathstar51]

You say it’s not good to keep the fan running when at speed and better to have it on when stationary . So how to do that? By a thermostat?

[@conorbrankin6284]

I live in TX. Having overheat issues. I think k a high capacity pump might help. Thinking of GWP0134HP. Good choice? Any help appreciated.

[@troybradshaw7058]

Whats the best radiator to replace the standard one, 2 Core or 4 Core for the hot Italian summers? Same for thermostats and water pumps?

[@classicminidiy]

I would go with a 2 core radiator for a hot climate, a "deep impeller" water pump, and a thermostat that opens earlier (at a lower temp) than standard like a 74°C Thermostat.

[@troybradshaw7058]

@@classicminidiy Grazie, plan is to go with the 2 core radiator from fletcher, a high pump capacity water pump and a 88 degree thermostat. After a complete flush, will see how she runs. Ciao..

[@snakeplissken2148]

Hehe, the zip ties. Once i installed an additional oil cooler into my polo. I said to me "mmh lets just put it with zip ties for a test and see how its performing..." That was now 5 Years ago...

[@leum2007]

Instead of wiering it to a toggle swit h could you wire it to the brake pedal. Whilst sat in traffic I generally have my foot on the brake so if I only need the fan on when sat still it makes sense to me to make the brake pedal or even the handbrake the switch.

[@farside87]

My concern is driving thru a small puddle and the front wheel throwing water onto this fan. Being a cheap fan, I don't think there is any water proofing. can't see it lasting too long. However, I do like the idea of adding an extra fan to the cooling system.

[@Kevinspizza]

Thank you for the awsome information , reduced my temp gauge from 95 % heat on the gauge to a cooler temperature

[@raychambers3646]

Could you add a small fan to aux rad?

[@classicminidiy]

Definetly. Would be a great way to help move more air while you’re sitting still.

[@jimmyd7071]

We have a Radtech aluminum with both mech and electric, a festa rad in the front in series, another elec fan in the right wing. The most important part you left out is an expansion tank plumbed to the suction side of the pump. An expansion tank is not an overflow bottle hooked to the radiator cap.

[@miker252]

Flipping the fan won't change the air flow direction. The pitch of the blade will still be in the same angle relative to the rotation. You would need to reverse the motor electrically or physically.

[@classicminidiy]

That's a good point only swapping the polarity of the leads will change the direction the fan is blowing by reversing the fan blade spinning direction.

[@user-du8cs8sn2v]

Correct, and look at the rotation when he connected it to the 9v battery, it's incorrect. He got the polarity correct for the desired airflow direction, but the blade should have been flipped.

[@milesborg9812]

Hey, nice video, very helpful. Why have you painted the interior of the mini black? Is there any specific reason? Looks awesome.

[@classicminidiy]

I painted it black back when I had the car painted because I actually didnt know they were supposed to be body color. So its just been black since then haha.

[@jrobpat0154]

A better way of connecting the second radiator (heater core) would be to connect it in parallel with the heater hoses using tee piece joiners. The existing method connecting it in series with the heater means that there is only flow when the heater is on which is in cooler weather when it is probably not needed

[@flatinsixth]

I have attached my fan direct to the rad using those two piece zip ties and soft pads. It does mean the inner wing slats need to be removed and the fan split from the rad (new zip ties needed) when any rad or need to remove it is needed. Works well though in standing traffic for the 3 days of hot weather we get in the UK....

[@SamHocking]

I've never really understood why the mini mechanical fan pushes the hot air surrounding the hot engine through the radiator? In turn, this electric fan is simply doing the same. Why not pull the cooler air from the wheel well in the first place and then when travelling at speed, the air through the front grill will do its thing anyway?

[@jrobpat0154]

If you are moving and the engine is running hot and you turn on the fan you would have two air flows opposing each other, making the situation worse

[@franciscomelendez3894]

I heard of a race Mini, that did just that, change fan direction, but had to block the front grill. I thought of doing that too... 🤔

[@adamzimmerman9459]

great job so helpful continued success! Adam

[@classicminidiy]

Thanks 👍

[@cal844]

I use an engine driven fan and the 12volt fan to pull the air through the rad. By the way your mini isn't a mark one mini 😉😉 you might want to check the vin isn't In the scuttle ..... You dont need a relay for the fan, I run mine on a switch in the dash and have a fused supply from the white wire on the fuse box.

[@classicminidiy]

Lol why do you think it’s not a mk1? 🤔 I have the heritage certificate and everything. Everything matched aside from the engine as that wasn’t original.

[@cal844]

The fresh air ducts are in the wrong place, amongst a few other items, but each to their own, keep making the videos as you do a good job

[@TairnKA]

I was thinking you may consider adding a temperature sensor and a three way switch (on/override, off, auto) so it automatically turns on when it gets hot while stopped but as you've indicated it can reduce the efficiency of the cooling. Ok, let's get complicated and have the "auto" setting also connected to the brake (and parking/emergency brake) sensors so if the temperature is high, when the brakes are applied, including parking/emergency brake the fan turns on. The "on/override" switch setting is for cooling while parked but turn it off to prevent battery draining. ;-)

[@shriramvenu]

i use a radiator plug with built in 85C thermostat which is wired to the relay that drives my aux fan. That way the fan only comes on when the engine gets too hot, so that you arent over cooling the engine. most of the time however the fan never comes on even when idling. it does come on briefly if you rev the engine a bit at the lights, but then goes off again after a few seconds. this is proof that i have a healthy cooling system.

[@sam._.buswell8181]

I’m in England and even in traffic jams they always used to overheat these new electric fans are significantly better than the engine driven ones

[@hosrow]

What relay did you use. Did you experience bad air flow during drive with the fan on? It's counter intuitive!

[@shriramvenu]

yea without a proper shroud the additional fan may just make it harder to push air through the radiator, as opposed to pushing air around the radiator, when at speed

[@SuperLEEEDWARDS]

That is 1 sweet mini you have there , I have had my share of minis from the age of 14-15 to racing the first 1 on a proper track at 18 then life and girlfriends move on but now at 47 I still have the bug and would love another 1 cheers for the vids keep them coming especially about suspension set-ups camber-castor would be great cheers SCOOBS UK.

[@pavandeepchadda9360]

Hey , could you make a video on all the cables and hoses and everything that should be connected to a engine. I got my mini sprayed and the spray guys left everything unplugged and all non engine engine parts are in a box (radiator, heater, windscreen wipers and motor, and a lot of cables) so i'm not sure what to do.

[@pavandeepchadda9360]

I know this is a lot to ask, but maybe also spark plugs, speedometer and basically everything in the engine bay if possible please. I have no idea what to do

[@Jagmandave1]

It get's hot here in Kansas too, I found an inexpensive aluminum radiator off Ebay did the trick.....my car used to get hot on long highway drives as well as stop go driving in town. Now it runs exactly where the thermostat is set. I also use the Evo style water pump.

[@yvonnelee6799]

Such a timely video for me! I've been driving my 1994 for just a few weeks and overheated two days ago. I'm new to the Classic Minis so I was a little concerned that I might have gotten a dud. I'm glad to hear that it's not uncommon. Being American living in Japan makes it a little difficult to communicate with the Japanese Mini owners for advice. Thanks so much for the detailed video!

[@cal844]

Make sure the engine is actually overheating as the guages are junk, so inaccurate. My 1980 Clubman Estate is at 83.5°c thermostat temperature and the guage is at 3/4 lol

[@snakeplissken2148]

@@cal844 the whole electricity on the mini is a snakenest of wiring horror. But yeah, i think mini owners found the charm of this shit. I actually have a mini in my shop for maintenance work. i replace the temp gauge with a vdo and the oil pressure with an electric sensor. Really, this tube from engine to oil gauge is just rediculous, because it is not venting itself.

[@RobinTheMini]

I live in Spain. If the cooling system is in good condition, there is no need to install any additional fan. The difference between a Mini in the UK or in hotter countries is solved just with the proper thermostat (74º, 82 or 88ºC available)

[@milesborg9812]

Agreed. Most Mini heater problems are solved by returning the cooling system to original and proper maintenance.

[@張博倫-r2j]

Agree, the Mini was designed with the Australian market in mind and in 1963, 20,900 minis were sold. Australian summers often have days over 41 degrees or over the old ton in the old measurement. In fact the Mini was more reliable in the heat than several other English cars sold in Australia, such as the Hillman Imp and Vauxhalls

[@callumaustin284]

Hi Cole, great vid, was just wandering how you covered up the big hole behind the centre speedo in the bulkhead? My mini just seems to leave this completely open to the elements, Thanks

[@classicminidiy]

I used a piece of sheet aluminium that I trimmed to shape, painted black and covered with foam on the back side. Then I bolted it to the bulkhead. Works great!

[@vasilisleo100]

hello my friend. great video again can i ask you? i want to change the steering in my mini 79. did u have something to recomment for me? were to order and what type is better for 10 wheels?

[@scottderuyter3812]

Fan blade on backwards too

[@classicminidiy]

Thats not correct, the fans is installed properly. Thanks for the concern though!

[@scottderuyter3812]

Just meant it’s another reason for possible over heating

[@classicminidiy]

Ohhh totally misunderstood what you were saying. 👌🏼 I thought you were telling me my fan was backwards.

[@scottderuyter3812]

Great vid, just trying to help with another possibility

[@paulbrenton939]

My Mini was used as a donor for a Banham Sprint, It has a forward facing RAD on a 998 cc engine. It use to run HOT until I changed the small WATER PUMP for the larger 1275 cc model

[@newuk26]

The only thing you need to watch with the zip ties is if they’re plastic, heat from the radiator can melt them

[@gaaldonat]

So what’s with the banana? That’s my only question.

[@paulhotson5820]

What about a 3 or 4 core radiator and change the thermostat .

[@classicminidiy]

I don't have the ease of swapping out for larger radiators on my car due to the space available with the mk1 radiator shroud on the body. However that said a good aluminium radiator is a must if you have space and should be adequate enough to cool most minis.

[@thebluep0tat0]

Couple points here that may need to be clarified from my experience. Leaving this same fan on while driving does not make things worse. Second, I tried shroud and no shroud and didn’t see massive differences in efficiencies. Third, you didn’t do any data logging around the temp differences....I did this for a few weeks. Having this fan set up the same way you do, only stabilizes the temps from going up when at say a stop light in HotLanta. I have a new 1293 with a larger rad so doing all the right things....I just needed to stop the heat Creep in the summer and solved it with the same placement as you and no shroud . You should data log your temps as well when you do a video like this...it’s the end game, the proof point. Otherwise, why even put the fan on to begin with?

[@mikemc7704]

Nice little talk about the fan connection. You have made it simple.

[@harow69]

Hey mate unless you run an electric water pump there is no need to run the fan when the motor is off. There is no circulation to cool.

[@classicminidiy]

Good point thanks for the info!

[@philjones6025]

Anyone looking at making this modification PLEASE DO NOT copy that electrical drawing shown. there are no fuses so if there is a fault with the fan, say it stalls it will try and draw excessive current from the battery, thus potentially causing a fire. you MUST add a fuse in the feed from the battery to the relay!!!!! also there is potential if you forget to open the switch when you leave the car of flattening the battery, you may wish to consider taking an ignition switch feed to the new switch so that when you switch the engine off the fan will stop. the circuit you ned for this is a green wire. (this also feeds circuits such as wipers, brake lights, turn indicators), if you have a later model where the key switch is on the steering column better still you may choose to use the Aux position ( ie the radio feed) this is a light green with a white trace. also remember that if in traffic and you turn the engine off because the temperature is high the fan won't help that much as you need the engine running to keep the water pump going. something else you may wish to do is to remove the cooling system thermostat, this is designed to open at approx 88 deg c. but even when open this does have a restriction in the water flow thus effecting cooling. not a problem where ambient temperature is lower but in federal markets, every little helps!!!

[@classicminidiy]

Phil thank you so much for calling this out. I was so focused on explaining the way relays work I completely forgot to add a detail about adding a fuse to the circuit. I have added a pinned comment so this detail is not lost to other people reading the comments. Thank you again.

[@classicminiworkshop]

Nice video Cole

[@classicminidiy]

Thank you!

[@classicminidetails8887]

Great video mate, really enjoyed it. Still not impressed enough to become a patreon. Love you.

[@classicminidiy]

OH YOU!!!

[@laughcorner7550]

Great videos pal you wouldn't believe that i built a 1293cc with your videos.

[@classicminidiy]

That's so cool! I am happy that they have helped you out. Are you enjoying the 1293?

[@laughcorner7550]

@@classicminidiy yeah I'm enjoying man thank you so much, I did almost everything by myself, all the way from South Africa but shipping mini spares from UK was expensive.

[@craigharmon7738]

Good info! I'm running a stock setup on my '67 Cooper S (including fan shroud) AND the "hot-climate" 6-blade fan. Knocking on wood, the system is working well to sufficiently cool the 1275 even in stopped/traffic summer heat (95F). Except for the winter months, I run a 20% antifreeze-to-water ratio vs. 50/50. Water has a better cooling capacity than antifreeze. I also run Redline's Water Wetter in the mix. This recipe is working well for me - recommend to others.

[@HFigueira]

Awesome, Cole! I've been thinking about adding a fan to my Mini as well. Where I live, it gets super hot during summer, so it would be an awesome thing to have. Just not sure if the 13x7 wheels will touch it when turning 😅but since my car doesn't have that extra cowl around the radiator, I'll probably attach it to the radiator. Thanks for one more awesome lesson! 🙏🏼