sorry, 2008 car question - coolant bleeding

[rapidyellow]

have asked on peugeot forums but nobody wants to answer

two weeks ago I had to take the radiator out of the Mrs Pug 308 HDi, to get better access to the front of the engine, cat/dpf was also removed, I noted that the AC rad was holed [its not worked for months], so have bought a new one, anyway after I done the job I was in there to do, put the radiator back and filled with coolant, and all good, heat in heater - yes.

yesterday I dropped the rad out again, and put the new AC Condensor in [yet to have it gassed, - next couple of days], put Rad back in and filled with coolant, this time I am not getting any heat through the heater. One thing I did note was that when I filled it this time I didnt have the heater set to hot.

there are two small bleed points, one on top of G/B, the other on the top heater inlet [or could be outlet] where it goes through bulkhead, not possible to see it with actual eyes so it was a case of feel for it, I think I can feel coolant coming out when opened, have tried letting engine run at a constant 1500-2000rpm to see if it clears, or needs more coolant, I have certainly not put in as much as what came out.

so it obviously has an air lock, what am I best doing?

coolant is circulating the engine and thermostat opens ok at temp.

of course no heat is required at the moment, it will continue to be driven but coolant level checked.

should I drain it down, and try refilling again?


any advice would be welcomed.

[Rich]

Make a funnel from a big container or bottle and a section of old radiator hose that brings the water level way above the bleed points and try again. Draining and refilling isn’t the fix here. The heater assemblies on these are a blend door so the matrix has full flow 100% of the time so that also isn’t the issue. With the engine running with a good head of water above the tank try re-bleeding, starting at the block and head bleed point and when that runs bubble free move to the heater hose bleed.

[BritBrick]

It's been a long time since I had my hand up a 306, but have you found all the bleed points?

There is a service tool that extends the neck of the coolant tank upwards for filling and bleeding or, as Rich says, you can bodge one out of a plastic bottle.

Or...

Give the neck of the header tank a good wipe clean, place your lips round it and blow gently while opening the bleeding nipples. That will work, but is a bit gross.

[rapidyellow]

thanks

have found a bit of old rad hose, and have cobbled something together that will push into the header tank with a large upturned bottle acting as a upper filling thingymibob

next chance to have a look at it will be monday afternoon

might take battery off as I will then have a better view of the rearmost bleeding point.

[mk2cossie]

Easiest way I've bled Peugeot engines over the years, is with the bleed screws out and the engine idling.

Keep topping up the coolant til you get a steady stream from either bleed screw, wind in the screw and wait for the next one to stream, and repeat 👍

[rapidyellow]

not winning

bled the rear bleeder this afternoon, coolant coming out with a good stream, but still no heat at the heater set to hot.

I drained it down again and refilled it slowly with bleed points open, run engine [peugeot tech doc says it can be run at 1500rpm while bleeding the matrix bleed point, the bleed cap is literally a tyre valve cap, it was pushing hot coolant out, and the bleed point for the matrix is on the OUT side [top] of matrix, so coolant is going through it.

See system pic




The pipe I have marked [IN RED] A is getting hot, this goes to the IN of the matrix, and you can see the bleed point on the OUT [top] of matrix [no matrix in that pic, but you can see where it goes]


When I originally drained the system the other week, it has the correct coolant in, was clear with no silting. And as coolant is going through the martix, hot both sides, WHY THE F!! is it blowing cool!

Have ordered a stepped barb adapter so I can join it to Pipe A with a hosepipe, just to prove to myself there isnt a blockage.

Just fuming right now.

[lebowski]

Broken diverter flaps under the dashboard? Meaning it's blowing cold air from outside rather than air through the matrix.

[rapidyellow]

no can mechanically feel and hear they are ok and there is a change in temp and air flow when adjusted to either hot or cold.

the hot is "barely warm"

[edwagon]

Are you sure that the engine is coming up to temp fully? and that the thermostat starts off closed, then opens correctly?

Like from cold, the top hose gradually gets hotter and hotter while the bottom hose is stone cold, and then just when you're starting to worry that the top hose feels too hot for too long, the thermostat opens and the bottom hose suddenly gets warm?

Sounds like the heater hoses are a pain to access, but do they feel hot?

If you sit in the car and hold the rpm a bit higher (say 2k) can you hear bubbling or gurgling in the heater matrix?

[rapidyellow]

Are you sure that the engine is coming up to temp fully? and that the thermostat starts off closed, then opens correctly?
yes, its definatly coming up to temp just like it always has

Like from cold, the top hose gradually gets hotter and hotter while the bottom hose is stone cold, and then just when you're starting to worry that the top hose feels too hot for too long, the thermostat opens and the bottom hose suddenly gets warm?
yes

Sounds like the heater hoses are a pain to access, but do they feel hot?
the rearmost hose with the bleed cap on, is a pita! its a full arm length away under the bulkhead behind the airbox, cant see it, can only feel where the cap is, remove it to let coolant out, and put it back on single handed. After a few mins of engine running it does get hot. To the point where its making my fingers hurt and then its case of pu the cap back on and give up, the "cap" is the same as a good quality car tyre valve cap, so tiny/fiddly and easy to lose - done that, but found it.

If you sit in the car and hold the rpm a bit higher (say 2k) can you hear bubbling or gurgling in the heater matrix?
no, cant hear that.


this morning I have been out to check it, the coolant level had sunk slightly from yesterday (I marked its level) , I open the rear bleed cap at the matrix and some air did bubble out, I then run the engine to get more to come out but it was just a stream. The Mrs is out in it this afternoon on a dual carriagway so some good revs and running, will check it again in the morning when its cold again.

[rapidyellow]

a closing update

the heater matrix is in the lowest part of the dash just underneath the centre console, youtube videos show that its easy to get out, after removal of a kick panel

HA

a serious amount of industrial words and a lot of sweat got the matrix out of the car, it was clogged with stuff that looked like sand, I got it running cleanly and put it back, HA whoever designed those clips that hold the coolant pipes to the matrix is mental! what a £$!%! of a job! I don't think the clips are designed for a second use but I had no option and one of them was suspect. But its holding so I have everything crossed it doesnt ping off and give me a footwell full of coolant.

coolant back in, bleed it up, run engine, HEAT.


not my video