Technical 500 airlock
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Technical 500 airlock
Presumably a 1242cc petrol..
The main bleed point is where the heater pipes go through the firewall..
It's a Small Plastic screw,
You could use a flat screwdriver to undo it... But ONLY TIGHTEN WITH YOUR FINGERS
it's got an O-ring under it so will seal ok
Open it slowly 1/4 turn or so once you start the engine.. Coolant will start to dribble out once air is evacuated
Practice this with motor off and cold
Then do it when warming and running
Obviously don't do this HOT
AS RISKS of Scalding, Hot surfaces AND RADIATOR FAN!
The main bleed point is where the heater pipes go through the firewall..
It's a Small Plastic screw,
You could use a flat screwdriver to undo it... But ONLY TIGHTEN WITH YOUR FINGERS
it's got an O-ring under it so will seal ok
Open it slowly 1/4 turn or so once you start the engine.. Coolant will start to dribble out once air is evacuated
Practice this with motor off and cold
Then do it when warming and running
Obviously don't do this HOT
AS RISKS of Scalding, Hot surfaces AND RADIATOR FAN!
Run the engine so the fan kicks in ie. hot.
Probably just needs run to work the air out before bleeding.
Squeeze the pipes may help a bit. Don't get burnt
Probably just needs run to work the air out before bleeding.
Squeeze the pipes may help a bit. Don't get burnt
Yes 1242cc, thanks very much for your replyPresumably a 1242cc petrol..
The main bleed point is where the heater pipes go through the firewall..
It's a Small Plastic screw,
You could use a flat screwdriver to undo it... But ONLY TIGHTEN WITH YOUR FINGERS
it's got an O-ring under it so will seal ok
Open it slowly 1/4 turn or so once you start the engine.. Coolant will start to dribble out once air is evacuated
Practice this with motor off and cold
Then do it when warming and running
Obviously don't do this HOT
AS RISKS of Scalding, Hot surfaces AND RADIATOR FAN!
Are you familiar with the best method for maintain the coolant level..?
In dull light.. Or Dark
Shine a bright light/ torch against the sight tube on the side of the radiator
Look from the other side, you can spot the fluid level easily
You don't need to disturb the cap
That’s a good tip, thanksAre you familiar with the best method for maintain the coolant level..?
In dull light.. Or Dark
Shine a bright light/ torch against the sight tube on the side of the radiator
Look from the other side, you can spot the fluid level easily
You don't need to disturb the cap
The system is self-purging so it should sort itself out, if there is enough coolant in the header (moulded as part of the radiator).
The little bleed screw makes it easier; as above, undo it so it's loose.. run the engine at a little over idle, to get the coolant moving through the heater.. and as soon as coolant starts coming out, just do up the screw again. You can do it with the engine cold.. and watch out for the aux belt in case it tries to eat your hair/clothes/fingers etc.
Ralf S.
The little bleed screw makes it easier; as above, undo it so it's loose.. run the engine at a little over idle, to get the coolant moving through the heater.. and as soon as coolant starts coming out, just do up the screw again. You can do it with the engine cold.. and watch out for the aux belt in case it tries to eat your hair/clothes/fingers etc.
Ralf S.
Thanks Ralf, I’ll have to do it when she brings the car over again, it seems straightforward enough. She has a friend with the same car and problem after the belt and pump change and the heater isn’t working, we’ll pass the information on to them as well.
John
John
I had Fiat do our belt, even after a year you can still hear bubbles in the system not that I've tried bleeding it, I noted they overfilled the header tank probably to allow for air at first ?
If the coolant has not been bled properly in the first place air bubbles will take time to move out to the bleed point and/or expansion tank.
Bleeding thereafter, as John2020 notes is an ongoing job as air finally gets shifted.
Try bleeding a radiator in the house once air enters the system.
If the OP has limited access to the car, I'd suggest he drains in a bucket and refill properly.
Bleeding thereafter, as John2020 notes is an ongoing job as air finally gets shifted.
Try bleeding a radiator in the house once air enters the system.
If the OP has limited access to the car, I'd suggest he drains in a bucket and refill properly.
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I found with mine that the air was reluctant to shift!, remembering similar problems on my old PAJERO4x4 i drove the car half way up my axle ramps to raise the front higher than the rear, which encourages the air to rise to the system highest point letting it bubble out whist refilling the expansion bottle stroke /tank at the same time did the job.
They fill the header "high" so that the level is higher than the bleed screw.. to help it push the air out through the bleed screw. They ought to have sucked the excess out once they finished..
Ralf S.
