car radiator

[nescafe1]

can anyone please help me.
how do you bleed a car radiator as my car is over heating and would like to empty the rad and try filling it up again to see if it helps.

many thanks

[NORMANTHEDOG]

why,that will not do anything for it,you dont bleed car radiators like your home ones,you have a problem if its overheating and losing water,fill the rad up with water and run the car,check there is no leaks in the rad itself and all the pipes and hoses that come off it,you might just have a split in one of the pipes,check the jubilee clips are tight,it could also be your thermostat stuck,or worse ways a leaky rad itself.

[mr rusty]

You really need to consult the relevant manual for the car-what car is it? Presumeably you think there may be airlocks in the system, and want to drain/flush/refill to see if it helps.

Here's a few general pointers: Depending on the car, the refill and bleed method differs, and can often be quite complicated.

Some cars have small bleed valves in the system (My XUD engine, for example, has two bleed valves: one in the thermostat housing and one in the rad top) and some cars require you to rig up a high level header tank (usually home made from a plastic pop bottle) See if you can spot any small valves in the cooling system (but don't confuse them with aircon access points) .

Others can only be really succsessfully bled by removing aa heater hose and running the engine until the air is expelled and water comes out (small Fiats of ye olde days)

When you've drained the system, flush it both ways with a hosepipe and also use a chemical cleaner- if you have blockages or silting this will help lots. Some cars (205 GTi's for example) were very prone to rad silting and consequent overheating, and a regular flush/clean made a world of difference.
Once you have the system clean and refilled/bled, then you can assess the problem, if any, more accurately.

[Northumbrian]

Norman mentions the thermostat. Check this first if it's easy to get to. It's not a difficult job but partly drain the system before you start.

[kwicky]

Thermostats when faulty usually stick in the open position because of hard water. If this is your problem your engine would run cold. I would suggest your problem stems from a blocked furred up radiator stopping the cold water from circulating. When the engine is hot, turn off the engine and feel near to the base of the radiator... if cold then this is your problem.

[nescafe1]

Thanks for the replies.

Sorry I should have explained in more detail.

The car is a Ford Orion LX, L reg 93-94
The temp goes up within minutes and when I feel the rad it is cold but the pipes and hoses are all really hot.

I have also noticed that there are tons of cat hair in the engine (probably from them climbing under when the weather is cold) so I am not sure if that has anything to do with it ot not.

Many Thanks

[maxximus]

waterpump impeller broken? no circulation. fill rad, disconnect top hose, run engine. coolant should flow.

[maxximus]

bleed nipples are on systems where rad is lower than engine and rad lines. it also helps to park the vehicle on a steep incline nose up when burping a rad.

[nescafe1]

Again many thanks for the responses,

I managed to bleed the rad and now it gets hot all over.
But it seems my Cooling fan don't come on and the car over heats.

Any Idea on how to test the fan to see if it works?
How to bridge the connection to have the fan going constantly?

Just to remind you, Its a L reg Ford Orion, 1.4.

Again Many Thanks

[gaz1250]

Could be the fan switch thats gone or the temp sender