Pug 405 - how do I drain the coolant? - GeordieGuy
Tried to drain the coolant in my wife?s diesel 405 TD ?96 today. However, nothing will come out ? not even a drop! Coolant is clearly there in expansion chamber ? have opened bleed valve, left expansion chamber top off and even run engine to try and pump the old coolant out. The rad is fairly new, so I?m sure it?s not bunged up with sludge. This one?s stumped me ?. Ideas, suggestions and thoughts welcomed ? as always. Thanks in anticipation.

{Subject header amended to make less vague - DD}
405 'Magic' Coolant - Armitage Shanks {p}
Have you looked for a drain plug in the bottom the radiator core? Otherwise why not diconnect the hoses and drain it that way. For a guess I'd say that if you are having that much trouble getting the water out you may finish up with a lot of airlocks when you try to re-fill it. Take care!
405 'Magic' Coolant - GeordieGuy
Thanks ... as a last resort I will remove hoses, though these then often seem to leak for me when re-fitted, so reluctant to do so. Drain plug is open, so gravity should be doing the trick with everything else open, even with air-locks??
I know how overheating can quickly crack the heads in these Pugs, so I guess I need to sort asap.
Thanks for your thoughts!!

405 'Magic' Coolant - Armitage Shanks {p}
As it is a '96 = 10 years old might a new set of hoses not be in order?
405 'Magic' Coolant - GeordieGuy
Yes, you're probably right regarding new hoses. The car is still with us as, in every other respect, it's a brilliant (if aged) piece of kit - shame I can't say the same about myself!
405 'Magic' Coolant - Pugugly {P}
Thermostat closed (a guess ;-) )
405 'Magic' Coolant - GeordieGuy
Thermostat closed .... what are the implications of this, please??
405 'Magic' Coolant - Pugugly {P}
I was hoping you wouldn't ask. If the engine was cold, certain parts of the cooling system would be shut off for water circulating around the system, especially near the radiator so possibly no water would come out....well very little. No doubt now I am exposing my minimal knowledge and will get a severe verbal bashing as this thread progresses.
405 'Magic' Coolant - jc2
Poke a piece of wire thro' the drain plug hole;even if the thermostat blocks part of the system,water should drain the other way round the circuit-ie. back thro the rad.
405 'Magic' Coolant - GeordieGuy
Thanks to both of you. Heh, Pugugly, your understanding is way, way beyond my limited take on things ? your reply is appreciated! Still baffled, but I'll try the wire thing!
405 'Magic' Coolant - Hamsafar
Can you give the expansion tank the kiss of life with your mouth? You can put cling film over it first with a hole in the middle.
405 'Magic' Coolant - GeordieGuy
Thanks Ashok .... have tried this also, though without cling film!! Will use this next time. Didn't make any difference. Perhaps I need more puff!
Again, appreciate the reply .....
405 'Magic' Coolant - Edward
From what I remember, the expansion chamber is not the highest point in the system. Therefore, when you do finally get the coolant out be vary careful to go through the correct bleeding procedure when refilling, otherwise you will end up with an air lock which on these engines often leads to overheating and headgasket failure.
405 'Magic' Coolant - sierraman
From what I remember, the expansion chamber is not the highest
point in the system.

If so can the tank be dismounted and raised above the level of the cooling system?Remember doing this on old Renaults with the glass bottle expansion tank,it was held in place with rubber straps so that it could be unclipped easily,then hung on a hook on the bonnet.With the top off coolant would flow with the bleed valves open.
405 'Magic' Coolant - braindead
as i remember on them motors the only way to drain it is to turn the car upside down as the airlock situation means you cant drain it dry upright !!
all you can do is to undo lots of hoses but be very carefull to bleed it correctly
there can be up to 6 bleed points on french cars
405 'Magic' Coolant - GeordieGuy
Thanks for the last two replies! Still can?t get the radiator to drain but, if it ever happens, I?ll certainly be careful regarding re-filling this, re potential for air-locks. The expansion chamber is actually an integral part of the radiator itself so I won?t be able to lift this above the height of the engine block ? unfortunately. Any/all suggestions welcomed, as I?m still scratching my head over this one.
Open or Closed - Pug 405 Drain Cock - GeordieGuy
Thanks for all your helpful replies, re my query on draining a 405 radiator ? which won?t! (See previous thread). I?ve given up on this. However, with my neighbours having all come across to do their own bit of fiddling, I can?t recall which position is off or on! OK ? I?m a real dipstick, I know. There are only two positions: half-past and quarter past. The Haynes manual pictures a totally different twist drain cock. I think closed is half-past. But, as no water comes out in either position, I don?t know!! There?s a lesson here ? somewhere! Thanks for your patience.

{Moved to exisiting thread as relevant to it - DD}
Open or Closed - Pug 405 Drain Cock - AndyT
Usually a plumbing fitting would be closed with the lever at right-angle to the pipe / flow. Think of a washing machine isolating valve, where with the lever in-line = on.

Can't you poke a small screwdriver up the draincock to feel when it's open / shut?
Open or Closed - Pug 405 Drain Cock - GeordieGuy
Thanks AndyT - will get the car on a ramp and see whether the wire thing works. I blame the neighbours for twiddling all the knobs. Have run the engine until hot and the fans all kick-in accordingly, so assume coolant is doing its job. I guess I'll have to sort asap or, in theory, the coolant could starting spewing out on the next long journey.

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