Morris Minor Owners Club

Hi, I was wondering if anyone can help with this long term issue?

I've had my Series II since 1993 and used it as my main source of transport during University. When I finished in 1996 I decided to upgrade it and had a Marina engine put in it. However, since then it has always overheated in the traffic of London and despite taking it to the original garage (and one another) this problem has persisted.

The set up on the car is a Marina 1300 engine with a 5 speed Ford gearbox but with the original radiator. I have wondered aloud at both garages whether or not a new radiator would help but both just repaired the original one.

Has any one else come across this overheating issue or any ideas what it might be?

Thanks in advance.

Could try a 'lectric (Kenlowe or similar) fan?

I wouldn't entirely be suprised to find that if it's a mechanically driven fan you just do suffer from overheating in severe traffic. All the old mechanically-driven-non-temperature-controlled fan-cars I've ever been in have struggled in hot weather in severe traffic. The traditional fix is to stick the heater on on full blast on hot.... Which can be a bit warm in the summer...

The other old wives tale is to add a second fan blade (giving 4 blades).
I did this on my first Minor and never had any problems in 50 minute crawling commute. I had also twisted the blades a bit more to push a bit more air (well at 17 I thought twisting the blades would help because you know everything when you're that young - my dad often used to say 'it was made to be like that for a reason, so if changing it was going to help don't you think they would have done it already')

Since then I've never had any really bad commutes in a Minor so I can't comment if that really makes a huge difference or not.
On the average early 90's Eurobox it often helps to put the heater on full to give extra cooling however I've never thought it gave much benefit on a Minor as when the thermostat is fully open and the revs are at tickover it doesn't push enough water to the heater to really kick out enough heat. On my 86 cavalier (many years ago) thewaterpump must have been good, and the heater was so strong that you could see the engine temp drop from nearly red to medium in 5 minutes!

i used to have a scimitar ,they are famous for overheting ,the kenlowe really does the job quickly though, i also had a switch to turn it on manually,steve

On my 86 cavalier (many years ago) thewaterpump must have been good, and the heater was so strong that you could see the engine temp drop from nearly red to medium in 5 minutes!

On my '82 Golf it was similarly effective, and on my Yugo (the fan on that tended to forget to come on at all). The most effective was my ex's Nova. I remember sweltering hot summer days with the heater on full blast sat in a queue of traffic wishing myself anywhere else ;-)

I've never used it on the Mog, 'cos the only place i tend to get stuck in traffic is about 2 minutes from the house, mind you when the temperature gauge hit 200 degrees I did start to consider it (but it was soooo hot.... and the heater....? The heater was too hot to touch, wish it was like that in winter.).

Of couse, you should check that you don't have any problems with the usual radiator fuzz - and the pipes. I know Hebe had problems when i put the heater ON because the heater cables were completely ************!

Cheers for the information. I've used the 'heater on' method a few times with little result. The car just continues to heat up until the engine looses all power and then won't restart. Maybe the heater isn't powerful enough

I'll have a look on the net for some more information about kenlowe fan's, as that sounds like a good solution.

Thanks once again.

Hi Shiner

I have a 53 SII with a tuned 1300 in and have no problems at all with a standard radiator and single blade fan. You should have no issue with over heating as the standard radiator is far far too big for an A series.

Look at a 1275 mini or metro turbo they have radiators that a 1/4 to 1/2 the size

Check if you have an original SII radiator with heater take off at the bottom of the radiator?

Other thing to check is normal overheating things, is the water pump impellor in good condition? get a few tins of radiator flush and give the system a good clean out. Remove the termostat and drop in boiling water an check it opens..


For the 1st week of having my car on the road i suffered constant boiling and steam pooring out from under the bonnet. I changed the head gasket, water pump and swapped to a new 1000 style radiator only to discover that the raidiator cap was not sealing and after swapping it was fine..

I would look at all the normal overheating things and not worry about the 1300 being the issue!1

The car just continues to heat up until the engine looses all power and then won't restart.

Do you get clouds of steam and loud gurgling sounds?
If not then did you get rapid ticking of the petrol pump (fuel vapourisation is a common cause of running problems in traffic jams)

That's exactly what I did get with the petrol pump ticking but the garage I went to replaced the Morris pump with a larger (possibly the Marina) pump and that seemed to happen less.

What does fuel vapouration actually mean and why would it have been occuring? Anything that can be done about it?

That's exactly what I did get with the petrol pump ticking

Ah - now we're getting somewhere!

Basically when you're in traffic the engine gets very hot but there is no big flow of air through the engine bay. Therefore the heat from the engine (especially the exhaust manifold and exhaust) heat up all the surrounding components.
The petrol pipe is not that far from the exhaust / exhaust manifold so it gets hot too.


When the petrol is hot it turns to vapour and 2 things happen
1) the petrol pump doesn't pump vapour very well so it struggles to pull petrol up the pipe
2) the fuel vapour gets to the carb but in the absence of petrol fluid the car splutters or stalls and isn't happy to restart.

The float bowl on the carb also gets hot and you might get vapourisation in the carb too.

A stronger pump would be more likely to cope with it but it's not going to cure it.
There are heat shield kits available which slow down the heat transfer to the fuel pipe and the carb float bowl. With that you can sit in traffic for a lot longer without any problems. The heat shield itself is usually a piece of silvery coloured sheet metal cut and bent to a suitable shape with some fixing holes so shouldn't be hard to fit.
I think Grumpys supply them and probably someone else will do so as well.

Your description of what happens in point 1 & 2 is exactly what has been happening. I'm at work at the moment but I'll look at Mr Grumpy for the heat shield this evening.

Cheers for all the help from everyone and hopefully things should be fine for next summer.