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I was having some overheating troubles with my mk1 850 mini, but after a radiator service it is not smoking all over after 1 or 2 miles. Still i carry a bottle of water to pour some into after a long distance trip. Yesterday, after the longest trip I have ever took it to, I saw this rusty color clayish spill all over the sorrundings of the radiator, could anyone please tell me if ir means something worth to attend?

thanx

Hmmm,,,,, not good there mate.

Looks like there is a lot of rust and sediments for the water you have been using. That greatly affects how well the cooling system can work. It actually acts like a wool blanket - a thermal insulator!

Looking at how extreme it appears to be, I'd suggest seeing a radiator shop who can hot flush your entire cooling system. You can buy Radiator Flushes off the shelf, some are OK, but I haven't found any that are brilliant.

Once you eventually get it clean, be sure to use a good quality coolant that also has an inhibitor in it. Not all coolants do!

Also, be sure to change your coolant about every year or so.

Check your cooling fan is on the right way round. I didn't and had similar problems 3 years ago. All sorted once blades faced the right way Cheers. Mark

How long is the pipe on the back, how did the water escape? Through the cap...?
That radiator seems to be an early one. Is that a late cap with a short neck?

Hi Ricardo, the hose is a little bit longer than the radiator. It came with a 14 libs rad cap, but I bought a new 7 libs one with long neck, because it's suppose to be the correct one. I really don't know where the spill leaked, but the hose is facing downwards to the tire, and I think the cap seals correctly the mouth of the radiator cause otherwise I guess the car would smoke all over the place.

thanx

Give the cooling system good clean, make sure the radiator isn't blocked up, check that it isn't running lean at the top end.

I would be inclined to try a stronger cap too, My S had a 7lb cap which wouldn't hold the water in, I know yours is an 850, but might be worth a try.

As for fans, I have heard people say that they fitted their fan the wrong way round, and it sucked air instead of blowing it!
This is impossible, they blow air in the same direction whichever way they are fitted!
On a Mk1 the fan may work more efficiently fitted one way than the other, but I can't see it making much difference.

J

I can guarantee the way the fan is fitted WILL make a difference. My car kept gobbing water out over the bulkhead and on to the wiper motor (which then shorted out). The picture looks very similar to how my car looked albeit with less rusty water. Once the fan was turned around the problem disappeared. Car drove fine overall although I did not sit in traffic. The problem lay with the collant level dropping and the mess. Sorry to disagree so strongly but I speak from experience. Cheers. Mark

Hi Mark,

Which fan do you have, and which way round do you fit it?

I'm sure you agree that it blows air the same direction, whichever way it's fitted!

James.

Plastic 16 blade yellow fan. Mustn't move enough air is my take on it. Seems so insignificant I know but definitely did the trick. Cheers

100% the plastic fan has to be fitted the right way round

it makes a huge difference to its performance.

i see probably one car a week thats had the fan fitted back to front!

guru_1071 wrote:100% the plastic fan has to be fitted the right way round
it makes a huge difference to its performance.
i see probably one car a week thats had the fan fitted back to front!

Given that they even have "Engine Side" written on them, how do people manage this?


As well as this, the metal inserts are pressed in and have a large flange on the side
which should end up under the bolt-head. I would say that it ought to be pretty obvious
which way round the fan goes.

Maybe those radial bars have something to do with the performance variation....

Another thing to check is that the water pump is OK: Many years ago I had a cooling
problem and eventually checked out the pump. It was one where the rotor assembly
was made of pressed steel, rather like an alternator fan. Well, basically, all the "blades"
had rusted off and the resultant 2-dimensional star shaped "impeller" was not really up
to the job of pumping water....

Has the OP tried fitting an expansion tank?

Maybe the head gasket has "gone" and combustion is blowing into the water system?

I am one of the dorks who fitted the fan on the wrong way (once upon a time). Had a look and I can't see engine side written on any of the plastic fans I have????

Just on this subject it's amazing what a clean acid dipped block can make to the cooling system, my last block was dipped and what a difference.

rolesyboy wrote:I am one of the dorks who fitted the fan on the wrong way (once upon a time). Had a look and I can't see engine side written on any of the plastic fans I have????

The factory originals had it on there but I've noticed the replacements don't.

Just be mindful guys that these things wizz around pretty quick and while I've not heard of it in regards a Mini (but seen some big damage none the less), I have heard of people being seriously injured (and in one case a bloke died) from a broken fan blade being flung out while they were poking about under the bonnet.

When ever you have your fan off, have a look for crack and check the blades still flex OK. If in doubt, replace it.

When fitting them (plastic ones) think of the bolt bosses as having built in washers and you can't go wrong when fitting.

rolesyboy wrote:Had a look and I can't see engine side written on any of the plastic fans I have????

It's not exactly big writing, but this is what you are looking for... (Compare the size of the writing with the size
of the screw hole)

I have never had one without the writing on, so all of mine must have been "Genuine"...

Note the non-flanged side of the inserts.

Top Tip:
If you throw one of these fans away, remove and keep the inserts. I cracked one recently, probably due to
over-tightening... It was very easy to "borrow" an insert from and old fan that I had in the junk box. I made
a puller out of an allen screw, but it would have probably just punched out OK with a hammer and drift.

ianh1968 wrote:Given that they even have "Engine Side" written on them, how do people manage this?

the same people who fit the front calipers upside down, thats nearly as common as the fans been the wrong way...

guru_1071 wrote:the same people who fit the front calipers upside down, thats nearly as common as the fans been the wrong way...

I came across this just last week, a friend of mine couldn't get a pedal on his restored S, he thought the M/cyl was at fault, until I spotted the bleed screws at the bottoms of the front calipers...

So... standard Mk1 metal fans.... Which way round?

J

Hi James,
The metal fans go with the reinforcing arms towards the radiator and I've seen a few fitted the wrong way.

Al

Look at the end of the blade, its like an aeroplane wing, only works one direction.

Not quite true. They work better in one direction than the other but they have enough angle of attack on the blades that they will still work. Whether it makes much difference at road speed is debatable. I'd argue that if you are relying on the fan being on the right way round then your cooling system doesn't have enough spare capacity.

I'm pleased to say that the 1330 in my Moke can stay happy even when driving uphill on a 42°C degree day. My cooling system is nothing special, but its all fairly new so there's no silt in it.

Tim