406oc.co.uk

How do I get read of an air lock? I left it running for a good half an hour on idle (850rpm) with the lid off the expansion bottle and with the blue screw totally out on the Thermostat housing and the heating on full with the blower on max. The temp was still showing blue in the car.

In the engine bay the bottom hose was fairly warm......top hose that goes to the Thermostat was cold. I saw another little looking bleed screw that lives very close to the bulk head, I undid this and coolant came out with no troubles.

The only time I managed to get any air out of the blue screw on the Thermostat housing was earlier when the temp was showing 70 and this took me a 5 minuets of keeping the revs at 3,500-4000. Then when I started pushing the hoses listening to the air escaping all was good but the engine was at idle which then it went back down to blue, this only took a few minutes. Really don't know what is wrong or what to do?

ps...... I replaced the thermostat earlier

Any help would be great.

leave the car running with the coolant cap off

keep pressing firmly the rad pipe i use the thick one that goes to the thermostat housing

i press this firmly squeezing with both hands, also i do it with the engine off after about 2 minutes doing it with it running, you can feel the air in the pipes if there is any in

also i never use them bleed nipples waste of time if you ask me

i did mine today , replaced 4.5 litres of coolant for pure anti freeze

saying that tho, driving round the temp neele does stay low in winter and rises in traffic to about 90

i wouldnt say you had an air lock, usually it will overheat if you have an airlock

Thank you mate

Mine is the opposite.......

It rises very slightly whilst driving, just above the blue and when in traffic/standstill it drops back down to the bottom of the blue?

Mastiff wrote:How do I get read of an air lock? I left it running for a good half an hour on idle (850rpm) with the lid off the expansion bottle and with the blue screw totally out on the Thermostat housing and the heating on full with the blower on max. The temp was still showing blue in the car.

In the engine bay the bottom hose was fairly warm......top hose that goes to the Thermostat was cold. I saw another little looking bleed screw that lives very close to the bulk head, I undid this and coolant came out with no troubles.

The only time I managed to get any air out of the blue screw on the Thermostat housing was earlier when the temp was showing 70 and this took me a 5 minuets of keeping the revs at 3,500-4000. Then when I started pushing the hoses listening to the air escaping all was good but the engine was at idle which then it went back down to blue, this only took a few minutes. Really don't know what is wrong or what to do?

ps...... I replaced the thermostat earlier

Any help would be great.

On the 110 HDi the best procedure is this....

Open the plastic screw on the radiator (it's a 17/19mm round screw on top of the radiator).
Fill the system with coolant mix and continue filling until coolant flows out the hole where the screw is, continously.
Tighten up the screw and unscrew the black plastic bleed screw on the heater pipe close to the bulkhead leave it open until coolant comes out.
Run the engine until coolant floods out of the black screw then tighten it until the engine warms up,then open it until hot coolant floods out.
When you have hot water in the heater pipes undo the blue screw until water floods out (thermostat will be open) then tighten it up.
Check for a completely hot radiator and heater with the engine revving.

What about ye olde coke bottle?

Never used one or needed to.
You pour the fluid in with the radiator screw open, air is expelled, that's what the radiator screw is there for.Then you bleed out the air from the heater pipes, finishing with the blue screw on the thermostat housing.

Mastiff wrote:How do I get read of an air lock? I left it running for a good half an hour on idle (850rpm) with the lid off the expansion bottle and with the blue screw totally out on the Thermostat housing and the heating on full with the blower on max. The temp was still showing blue in the car.

In the engine bay the bottom hose was fairly warm......top hose that goes to the Thermostat was cold. I saw another little looking bleed screw that lives very close to the bulk head, I undid this and coolant came out with no troubles.

The only time I managed to get any air out of the blue screw on the Thermostat housing was earlier when the temp was showing 70 and this took me a 5 minuets of keeping the revs at 3,500-4000. Then when I started pushing the hoses listening to the air escaping all was good but the engine was at idle which then it went back down to blue, this only took a few minutes. Really don't know what is wrong or what to do?

ps...... I replaced the thermostat earlier

Any help would be great.

As i posted on pug306, coke bottle will sort any air locks.

I thought the problem was the expansion tank is lower than parts of the engine, the only way to get the air out is either park it on the kerb so the tank is higher or use a bottle stuffed into the expansion tank to raise the level that way.

I done a Wiki once http://www.pug406.com/wiki/index.php?ti ... _System%29 (hmm, it'll do I guess)

Btw I changed my antifreeze last week, it was -4 and I didn't think the engine would ever warm up Didn't take so long to cool down again though.

Thanks guys

Going to go out and give it a go in a moment. My Saph Cossie on idle keeps her temp, my 406 110 HDI drops her temp when on idle.........She needs to be either revved for 5 mins at 3,500-4000rpm to get her to just budge above the blue. My Cossie......I leave it running for a few mins on idle and its like toast, engine temp is upto normal.

The bulkhead bleed screw flows well with no worries, its the blue one that is a sod! The top pipe does not get hot and when it did after keeping her on 4,000rpm for 5 mins it squirted a little bit out and then I had to press the top pipe which started to get warm......result!! One trouble, my car was now on idle and I had about 2 mins to work on this top pipe as before I knew it the temp was on blue and no water coming out of the blue bleed valve

Going to try the bottle although it is only the blue bleed screw that is holding back the air. I will run her to temp via the 4,000rpm warm up with the bottle in the expansion tank with half a litre of coolant...........hopefully this should push any air out? I will have the blue bleed screw totally out whilst doing this..................

Sound good??!

Water/air will only flow out of the blue bleed screw with the thermostat open.....it's on the thermostat housing above the thermostat so the thermostat has to open and let coolant flow into the housing to be able to bleed it.

The coke bottle will only help when filling the system from empty.

The 110 HDi has a proper radiator bleed screw on top of it................


I give up

There's a lot of places higher than the bleed screws - the top hose goes up from the thermostat housing so forms an air trap, I think there's also one in the top of the radiator above the level of the bleed screw. When I was doing mine, once the thermostat opened I squeezed my top hose (how do I say this without ending up as someone's sig? ) with both hands half a dozen times and it cleared (no more bubbles rising in the bottle).

Before I cleared it I noticed if I revved it the level in the bottle dropped slightly (say 10mm), this has to be air still in the system being compressed. Once it doesn't move (or only slightly as the pipes expand) I reckon it's a good sign that there's no more air.

I didn't rev mine much but you could pull the retaining clip out of the throttle cable outer and move it along a bit to hold the throttle open. Also, make sure the cabin fan is off.

Bluddy HDis taking months to get warm

Just to give jasper some moral support here mastiff; he's a mechanic by trade and has worked on quite a few of these!
Chin up John, people do listen chap

Edit: The filler thread!

Here's the real thing from Pug: http://petrila.net/peugeot/Service/406d ... gi0ik3.htm

Hey, I always listen, but for those of us without heaps of experience I reckon this way is idiot-proof

Btw anyone else ever had to bleed a domestic c/h radiator above the level of the expansion tank?

Done guys.......Thank you all

I put 700ml of coolant/water in the coke bottle then turned the engine on. Lovely squirt from the bulkhead bleed valve then I undid the top rad screw........nothing, then my levels went from 700ml to about 200ml in the coke bottle and it started flowing out of the top rad screw as well as the blue bleed screw........Result!!