Technical help. draining/refilling cooling system uno
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Technical help. draining/refilling cooling system uno
remove the bottom hose on the radiator, allow to drain then refit, add your antifreeze 1.5l, and top up with water, then run the engine upto temp and keep your eye on the level refit expansion bottle cap, take for a spin then recheck. if a load of gunk comes out of the rad might be an idea of a coolant flush, make sure the heater control on the dash is on hot to empty the matrix Ant!
(CZ)enda
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I found it more practical to drain the system via the hose from the radiator which ends up at the heating matrix junction. Unclamp it from the plastic eyes which attach it to the bodywork, release the clamp on the end of the hose, put its end to the 5-l plastic bottle used for e.g. mineral water, then lower the bottle below the bottom edge of the radiator. Have the radiator cap unscrewed. All of your coolant should be caught in the bottle.
Disconnecting the lower radiator hose, although efficient, results in annoying spillage. Especially if your neighbor is looking at what you are doing on the car
.
Disconnecting the lower radiator hose, although efficient, results in annoying spillage. Especially if your neighbor is looking at what you are doing on the car
.
One other tip from me. When filling the system, find the small black plastic tap (about 15mm in diameter) near the radiator top hose, on the radiator itself (beside the expansion tank that's attached to the radiator).
Remove the tap and fill the expansion tank until coolant flows out of the hole (left by the removed tap), then refit the tap.
Look for a similar tap in the heater hoses at the back of the engine bay, behind the carburettor/injection system. If you find a tap there, remove it and keep filling until coolant flows out, then refit this second tap.
Doing this will bleed most of the air from the system, but you should still run the engine until warm with the radiator cap removed, keeping it topped up to a few cm below the top. Then allow to cool and recheck a final time.
The worst problems I've had when filling Unos have been when the heater valve is seized closed - can be really difficult to bleed air out if this is the case - so if your heater wasn't turning on/off properly, it may be a good time to fix this before you refill
Incidentally, good work in changing the coolant... people seem to forget the important anti-corrosive property of coolant, and then wonder why they have troubles later on with blocked heaters, failed water pumps...
-Alex
Remove the tap and fill the expansion tank until coolant flows out of the hole (left by the removed tap), then refit the tap.
Look for a similar tap in the heater hoses at the back of the engine bay, behind the carburettor/injection system. If you find a tap there, remove it and keep filling until coolant flows out, then refit this second tap.
Doing this will bleed most of the air from the system, but you should still run the engine until warm with the radiator cap removed, keeping it topped up to a few cm below the top. Then allow to cool and recheck a final time.
The worst problems I've had when filling Unos have been when the heater valve is seized closed - can be really difficult to bleed air out if this is the case - so if your heater wasn't turning on/off properly, it may be a good time to fix this before you refill
Incidentally, good work in changing the coolant... people seem to forget the important anti-corrosive property of coolant, and then wonder why they have troubles later on with blocked heaters, failed water pumps...
-Alex
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Remember to refill after thermostat opens to let coolant into the engine.
Morten.
Morten.
