99 2.0 petrol cooling system - Help Please - Phil T
Intend to replace the coolant in my 1999 (i.e. new spec) 406 2.0 LX petrol this weekend. Had a quick look over it to know what to expect before I scooted off to buy the antifreeze. Bedamned if I can find the cylinder block drain plug or the thermostat housing bleedscrew.

Haynes don't cover this vehicle yet - anybody out there know where they've hidden the drain plug and how many bleedscrews there are (I can only find the one on the heater outlet)?

Maybe I'll have to go to the (quick intake of breath...) dealer :-(

Cheers

Phil T

Edited by Pugugly on 28/02/2008 at 20:33

Re: 406 Cooling System - Help Please - james S
To drain you may have to undo the jubilee clips on the hose at the bottom of the radiator. Don't know about bleeding. I usually end up squeezing the flexible hoses for ages until it sorts its self out.
Re: 406 Cooling System - Help Please - Phil T
Thanks James - This will only drain the rad (in fact there's a natty little drain plug with an attachment for a length of tubing), surely there must be a drain plug for the cylinder block somewhere?

Phil T
Re: 406 Cooling System - Help Please - Keith Stockdale
I bet the Haynes manual for the older models will give you an idea.

A 309 I once owned had a number of air bleed valves. Make sure you find them all or it could be trouble!

Many cars dont have a drain plug for any part of the cooling system.

I'm really lucky. My Mondeo has coolant that you never need to change - a funny orangey colour I think.
Re: 406 Cooling System - Help Please - JohnD
Hi Phil - I think you'll find the block drain plug on the back of the engine. To reach it you'll probably have to remove the splash guard under the engine. You may have a drain plug at the bottom left-hand side of the rad. If so, you only need loosen it, not remove it. If there's no plug, you'll have to undo the bottom hose clip. Bleed screws are situated on the heater hose at the bulkhead and on the top of the thermostat housing. Some vehicles also have one on the top of the radiator. When refilling the system it is advisable to use a header tank. This can be a plastic bottle with the bottom cut out and suitably sealed around the expansion tank. All the best!
Re: 406 Cooling System - Help Please - alvin booth
Phil, Modern cars appear to be far more difficult to refill satisfactorily after a drain down. There has been many posts regarding the Peugot (PSA) diesel engine regarding this. In some cases I recall reading of air locks resulting in damage. I don't know if this applies to your petrol model but someone can perhaps advise if there are any particular problems.
alvin
Re: 406 Cooling System - Help Please - Richard P
Might be worth asking the dealer as to how much it costs. I had a cooling system flush and a new anti-freeze mixture for £35 all-in for my 2000 Vectra turbo diesel recently as part of it's 30K service. Quite reasonable I thought and this included a full cooling system check with a 6 month warranty on all parts of the system included also. See what Peugeot charge!
Re: 406 Cooling System - Help Please - Phil T
Thanks all for your responses. I do have the Haynes manual for the earlier model and it does tell me how the system *used* to be drained down (as per John D's post). However, things have changed on the new model - most notably in relation to the location (or absence) of some of the bleedscrews - The thermostat housing is completely different on the 138bhp engine.

If no-one's got any first hand knowledge of the 1999 variant I think I'll entrust this job to my friendly local independent PSA specialist. Whilst I don't object to paying him to do a professional job, it's frustrating that I can't do a relatively simple task myself due to lack of technical information. Maybe Haynes will be reissuing the 406 workshop manual soon - I did send them an enquiring email, but no response :-(

Thanks again

Phil T