13 replies to this topic

[24Seven]

Hey,

I drive a 1992 Italian Job with a mildly tuned 1275, including a heated inlet manifold (dont know wheather this is relevant to my problem)

Just got my mini back on the road after 2 months spent tarting it up and its now overheating! It was fine for the first two days back on the road but monday night i was driving home and noticed the temp needle climbing, by the time i got home and switched it off there was steam everywhere and coolant coming outa the rad cap.

There was enough coolant in it, its already had a new cap, new water pump and a new radiator in the last year and the system has been flushed.

Was wondering if maybe it could be the pipe through the inlet manifold or a blocked heater matrix?

Please please help, im having to drive my mums Mitsubishi Pinin which is slow and doesnt like corners

Any help would be very appreciated


Russ

[Sprocket]

What colour is the coolant? Have you replaced the Stat?

[24Seven]

Yeah, hav replaced the 'stat with another 88 degree as standard. Has new coolant in it, just wondered if there was a common place for the system to block up?

[fikus01]

could be an airlock in the heater system!!

[Grayedout]

Did you remove the fan and if so did you put it back on the right way round ??

[minipip]

could be an airlock in the heater system!!

we have kinda ruled out the airlock as he refilled the system and tryed again

Did you remove the fan and if so did you put it back on the right way round ??

i dont mean to sound cocky but its been running fine the past yr and the past 2 days since getting it on the road after the respray, the only thing i can think is the stat needs wearing in a bit as when we replaced mine i did a short journy, and then it decided to blow the contense of the rad all over my engine bay, but after that its all dandy now, ither that or the rad is shot?!?!?!

[Jammy]

What did you have done before the 'just two days' of driving?

You can still get an airlock after refilling it. Run the engine for a few minutes with the rad cap off to remove air.

Did you fiddle with the carb or timing? Running lean will cause a hot engine, so will the timing being out.

Also, bit of a silly one, did you check the stat was put in the right way?

[minislapper]

Thermostat wearing in? First I've heard of that!

You don't mean to sound cocky? Why do people ask for advice if they don't want to listen to it when it's given?

How have you ruled out an airlock simply because he refilled the system? The same airlock could still be present.

Try taking off one of the hoses from the heater and see if it's full of poo. There could be a blockage down one of the hoses.

[TOMMO0302]

I think 24Seven prob did want the advice....

Did you take the fan off..(i know it was alreasy asked and dismissed) but thats an option, could have been more traffic yesterday than the previous 2 days, a longer drive, higher ambient temperature, no heater on, more people in the car.....all would make that difference as to why it overheated yest and not previously.

[Sprocket]

Not intending to teach any one to suck eggs, but, Is the thermostat in the correct way up?

And, why will a blocked heater and or inlet manifold cause over heating?? Thats like saying race cars will over heat!!!

It has to be one or more of the following!!

Small impellor water pump, Pressed steel impellor water pump that has failed at the impellor, Thermostat dodgey or fitted incorrectly, Engine driven fan on back to front, Fan belt slipping, Fouling of the rad internaly, Fouling of the rad externaly, Failed head gasket( normaly spits the water out if cylinder to coolant passage), Cracked head or block ( worst case scenario)

The rad cap does not stop the coolant boiling when the engine is running, its function is to stop boiling when the engine is switched off. Boiling when running is prevented by the pressure generated in the block by the pump against the thermostat, so, if the pump aint up to it it will boil over and over heat, not necisaraly spit it out of the engine.

Edited by Mini Sprocket, 26 October 2006 - 06:20 PM.

[998dave]

Did you remove the fan and if so did you put it back on the right way round ??

which way's the right way round again? :-P

[Sprocket]

it says 'engine side' on the fan itself

[1984mini25]

which way's the right way round again? :-P

this way is

[fikus01]

blocked heater pipe could be trapping an excessive amount of air in the system!! air isnt very good for cooling an engine thats relying on water to do that job!! gives it too much room for expansion before the pressure cap will take effect!! and start increasing the boiling temperature of the water!!

yes thats right the pressure raises the waters boiling temperature!! too much air means a lot more expansion can take place before there is pressure!!

when i refill my engines i remove the heater pipe from the top of the head and fill the engine til water comes out of that then i let the waye coming out of that drizzly down the heater pipe til that fills up thne i chuck it all together!!

complicated but u cant get airlock that way!