Peugeot 306 cooling system

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JR
Posts: 27
Joined: 29 Jul 2003, 01:03

Peugeot 306 cooling system

Post by JR » 30 Jul 2003, 01:43

Hi,
Ever since buying my 306, I have noticed that the cooling fan seems to work really hard, even in light traffic, it has always kicked in reguarly.
I recently had the fan switch and thermostat replaced - both had melted and stopped the fan from working. I also had the radiator flushed of all the gunky residue that had collected when the engine over heated.
The fan is now back in regular action, but as I am now more vigilant about the heating problem, I have noticed that the oil is becomming quite hot. Steam, alomst smoke can be seen when removing the oil dip stick plug.
After 20 minutes of driving the temperature reaches 105 degrees and the colling fan kicks in, keeping the temperature just below 110 degrees and continues to kick in around every 10-15 mintues.
The problem seems to be with keeping the oil cool. Are there any other parts of the cooling system that I should have checked?
Any advice would be greatly appreciated.
cheers, JR

CITMAN
Posts: 407
Joined: 02 Aug 2002, 00:22

Post by CITMAN » 31 Jul 2003, 02:00

sounds like a head gasket problem.
Does the cooling system pressurise
Is there oil in the coolant and coolant in the oil
Is the coolant dirty colour i.e. brown signifying that oil might be present
Is there water droplets on the dipstick
Does it use any water if so how much
Is there any white gunge under the oil filler cap

JR
Posts: 27
Joined: 29 Jul 2003, 01:03

Post by JR » 01 Aug 2003, 01:15

Hi,
I had the cambelt and head gasket replaced six months ago.
- There is no water in the oil, but the water is a slightly dirty colour.
- It seems to be drinking a fair amount of water and am having to top up the cooling system once a month, with 1 litre of water.
- There is no white gunge under the oil filler cap and I have bled the system, so no air bubbles present.
It seems like the temperature is not being regulated. Any other car I drive sits around the 90 degree mark and the cooling fan only kicks in on a v.hot day or in traffic.
With this hunk of junk, the temperature reaches 105 and then the fan decides to exercise itself and continues to do so every 10 mins.
any further info or recommendations greatly appreciated,
cheers, JR

CITMAN
Posts: 407
Joined: 02 Aug 2002, 00:22

Post by CITMAN » 01 Aug 2003, 15:10

First of all is the car a diesel or a petrol engine and whats its size. But it sounds like a head gasket problem or maybe a warped cylinder head or block which was not discovered when you had the head gasket changed. Because you say that its using a lot of water 1 litre in fact and thats a lot, a sealed cooling system should not lose any water at all.
It maybe that you pressure cap on top of coolant filler tank is leaking either due to the fact that its faulty and letting coolant out or maybe the cooling system is pressurising and letting the coolant out.
My advice would be have cooling system pressurised by your garage and they should be able to tell you what the problem is.
Or failing this a compression test which should tell you that its headgasket problem.
Ps if your motor is running continuously at these temps i.e. 105 - 110c then you have a problem which needs to be sorted before the engine self distructs, because excessive temp is not good for any of the engine components i.e. seals etc.

CITMAN
Posts: 407
Joined: 02 Aug 2002, 00:22

Post by CITMAN » 01 Aug 2003, 15:12

Oh does the car puff out lots of white smoke from the tail pipe even when the car is at normal operating temp

David Goddard
Posts: 138
Joined: 26 Sep 2001, 04:39

Post by David Goddard » 02 Aug 2003, 02:22

You mentioned you have bled the air out of the system. I assume you did this with some sort of extension to the filler cap, as the 306 filler can is at a lower level than the cylinder head and is impossible to bleed otherwise. Opened all three vents in turn? Thermostat housing, radiator and heater bleed screws?

CITMAN
Posts: 407
Joined: 02 Aug 2002, 00:22

Post by CITMAN » 02 Aug 2003, 03:03

Daves right to properly bleed the cooling system you need to use a header tank, as this aviods the possibility of air being trapped in the upper parts of the cooling system.
I would drain and refill the system using a pop bottle with some kind of seal at the bottom and then refill it slowly squeezing some of the hoses as you bleed the system through to get rid of all the air. But failing this im afraid it brings me back to cylinder head, block sealing problem.
CITMAN

JR
Posts: 27
Joined: 29 Jul 2003, 01:03

Post by JR » 03 Aug 2003, 03:02

Hi,
It is a 1.8xt model and has done 69k miles.
I didn't realise bleeding the system was so complex, I have already emptied the cooling system, re-filled it, and bled with the heater bleed screws, but did not do the other bits, which I will now do.
I drove the car today and when driving at 40mph an hour, it was fine, temperature sits just above 90 degrees, but as soon as I stop at a set of traffic lights or am not moving for more than 2 mins, the temperature shoots up to the 110 mark and the cooling fan struggles to get the temperature back down. Eventually the cooling fan will bring it back down, but as the temperature has got this high, it struggles for the rest of the journey.
Is it costly to have the cylinder head unblocked? Someone mentioned to me that it could also be the raditaor that is the problem, apparently these are only good for three years in a 306? If the water in the radiaor is getting too hot, then it will not be able to cool the system properly?
It's looking like a garage job, if the bleeding does not work. Are there any Peugeot specialist garages you would recommend in the London or Harrow area that you would recommend? Citman, you seem to know your suff, so please send me an e-mail if you think you are able to repair yourself.
Once again thanks for your advice, as a novice it's great to obatin this kind of info.
cheers, JR

CITMAN
Posts: 407
Joined: 02 Aug 2002, 00:22

Post by CITMAN » 03 Aug 2003, 18:12

Sounds like air trapped in the upper parts of the system. get yourself a haynes manual becuase it shows the right way to bleed the system. I have a theory that when the engine gets hot the coolant expands and therefore if air is present this will pressurise the cooling system and force water out of the cap.
my zx 1.4 identical car to the 306 apart from the body shape and interior bits n bobs is still on its orginal radiator and its 9 years old. so the theory that the only last 3 years is open to arguements.

Ben83
Posts: 19
Joined: 28 Feb 2003, 19:04

Post by Ben83 » 04 Aug 2003, 20:11

JR,
I can't offer any help, as I'm a novice myself. However, like Citman my 1995 306 1.4 still has its original radiator, with no cooling problems. Its coolant has never needed topping up. If you need to top yours up that much, don't forget to add antifreeze, even in summer, as it has anti-corrosive properties as well as anti-freezing ones.
Citman,
you wrote:
> using a pop bottle with some kind of seal at the bottom
When I read the instructions in the Haynes manual, it was this that put me off flushing my system. Can you offer any guidance on how to seal the bottle to the tank?
Cheers,
Ben.
1995 306 1.4.

JR
Posts: 27
Joined: 29 Jul 2003, 01:03

Post by JR » 06 Aug 2003, 00:37

Hi Citman,
Thanks, I will head of and buy the Haynes manual this weekend and bleed the system corectly.
One last thing, does the cooling fan have 1 or 2 speeds? If it's the latter, I have a feling that speed 1 is not kicking in and it's going staight to speed 2, which is when it is too late.
cheers, JR