MG Metro engine cooling

[danoldo]

Hello,

I am currently in the middle of installing an MG Metro engine into my 1985 mini, which I have been re-building / restoring.

The engine is a 1275 MG Metro (with +0.020" rebore), Metro heated inlet manifold, 1 3/4" HIF44 carb, maniflow exhaust manifold and 1 3/4" twin box exhaust system, Minispares 2 cores radiator.

Firstly the usual problem - no by pass hose in the head. From reading other posts I noticed that one way round this is to drill small holes in the thermostat, although this way of doing things seems to get mixed opinions. I understand there may be a way round this using a cooper or SPI thermostat housing with the sandwich plate and bypass outlet underneath - is this correct? and if so what sort of Bottom hose do I need with this set up?

The next problem is with the heater take off, which I have drilled out. I have read a number of times people recommending this as it ensures cooling of the number 4 cylinder area. But, as I understand it, the only way to take water from this is to have water flowing through the in-car heater all the time. Is there a way round this? perhaps another type of valve or something?

Also, I have the metro oil cooler (water cooled) is it worth using this and if so, which is the best way to plumb it into the cooling system!?

If anyone has any cooling diagrams / photos, it would be a good help!

Look forward to hearing your ideas and thanks in advance.

Dan.

[JimexPL]

There are guys on here with far more knowledge than me, but thought that my experience might be of use.

My 1330 has run without a bypass hose and a drilled thermostat for 10 years/20,000 'enthusiastic' miles without a problem.
The headgasket has been replaced once when the top end was dismantled to retrieve the retaining bolt for the K&N!
It has overheated twice (on both cases when the electric fan didn't cut in due to a loose connection - I don't have a pump driven fan).
I don't have any oil guages so cannot comment on the oil temp, but the water temp used to read very close to hot when cruising down the motorway at about 4,500rpm for more than 30 minutes; with an oil cooler (aftermarket mocal type) on this came down to a more sensible level. For mixed driving it was fine without the cooler.

The heater take off is a new one on me, but presumably you could create a loop from the outlet to the inlet and have a 't' and one of the later type in line heater valves to control the flow to the heater. Having said that, not much heat comes from my heater when in the 'off' position, so I don't know how much of an issue this really is in our climate!

[danoldo]

Thanks for the info.

What I was trying to get away from is having to have the heater on (water running through it) all the time.
Your suggestion might be the answer, I wonder is this how the later mini's worked perhaps? with the other type of in-line valve.

[guru_1071]

danoldo said:

Thanks for the info.

What I was trying to get away from is having to have the heater on (water running through it) all the time.
Your suggestion might be the answer, I wonder is this how the later mini's worked perhaps? with the other type of in-line valve.

just plumb it up from the valve, through the heater, back into the bottom hose.

if it really bothers you, run one of the hoses through the heated inlet.

then just drill a couple of holes in the thermostat, though i normally replace it with a blanking sleave once the weather gets warmer.

i never run with the heater off in a mini, the heater fan yes, but the flow of warm air is never really hot enough to bother about when the motor is turned off.

to run the later spi or hif carb cooper method involves expensive bottom hoses, pipe convertors, different heater valves and is a load of messing that fills the engine bay full of heater hoses - not worth it to get rid of a luke warm draft around your ankles!!!