Overheating and rust in coolant

[Steve O]

Hi. Yes its me again. Ok,started up the montego today to take for a spin as weather was nice. After a short while the engine temp guage began to rise,i heard the fan come in so not unduly worried....but it kept on rising and eventually followed by a flashing red light. I about turned and took it home. On lifting the bonnet and letting it cool for a bit i checked the water in header tank. It bubbled out all over the place,but not blue or clear but brown rust coloured . Checked oil and no sign of water in it. Let car cool,topped up and took up the road again to which it then started to get hot again so took it back before it got any worse. Any idears what to check first? I'm guessing a coolant system flush is a definite? Could the thermostat be at fault? Many thanks...again Steve

[Doctordiesel77]

Petrol or diesel engine?

[Steve O]

2.0 petrol mate. 1988 Mg

[Jeff Turbo]

Petrol John
Steve , give the engine and radiator a flush out , also flush the rear water pipe and matrix pipes . Remove the thermostat and flush up and down the engine and radiator. You may only have a blockage.
when filling back up put the heater on full heat with the fan at full power and the engine running untill you get heat out if the top and bottom vents to clear any air lock

[Steve O]

Thanks jeff. I'm hoping just a blockage or air lock? Recently had it serviced as well. Whats best method of flushing ? Never done it before. Is it best to remove bittom hose and flush through top hose with a hosepipe?

[Jeff Turbo]

Thanks jeff. I'm hoping just a blockage or air lock? Recently had it serviced as well. Whats best method of flushing ? Never done it before. Is it best to remove bittom hose and flush through top hose with a hosepipe?

Remove top and bottom hose, flush down radiator then flush up, put something round the house at the bottom of the rad so it fills up then drain and repeat. Engine, if you can remove the thermostat top without snapping any of the two bolts again flush down and up so it forces water out the top through the bottom hose and repeat . Rear water pipe, remove the pipe at the rear of the thermostat housing and and both pipes into the bulkhead and flush through top and bottom again so it forces water out the top and bottom and repeat Once clear reconnect everything including a new thermostat gasket. You may also want to change the thermostat while you're at it
you say it was just serviced , did they do anything with the coolant change ?

[Steve O]

Thanks jeff. Great instructions. Looks like this weekend coming i will be busy? Hope this cures it?

[Steve O]

Quick update. Coolant system flushed and new coolant etc added. New cap, thermostat and thermostat housing. Old housing was very corroded, small pipe that takes water back to header tank was completely blocked. All running smoothly now, fan cutting in so just waiting for the next problem lol

[Jeff Turbo]

Quick update. Coolant system flushed and new coolant etc added. New cap, thermostat and thermostat housing. Old housing was very corroded, small pipe that takes water back to header tank was completely blocked. All running smoothly now, fan cutting in so just waiting for the next problem lol

Very good stuff, getting there slowly then

[Steve O]

Yes mate slowly but surely getting bits sorted. Its never going to be a concourse car but i actually dont want that. I like its war wounds,bit of rust,its patina. Still looks great though and i get looks and waves from people. For me has to be a useable classic I'm not afraid to " use" if that makes sense?