407 sw overheating

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trevor.kirton
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Joined: 04 Jul 2016, 12:40

407 sw overheating

Post by trevor.kirton »

Hi,

I have a 407sw HDI 136, i have had the usual challenging Peugeot problems.

in the last week the Water Temp has gone above the 90c and fans working as they should. there are no visual leaks and the coolant level is correct.
On my way home yesterday the temp went in the Red and the car showed STOP The car Now due to temp.
Before i spend an absolute fortune has anyone got suggestions to what it could be , mine is the Thermostat. Is there any way of testing the water pump is correctly working? ( I CANT PUT THE HEATERS ON DUE TO THE OTHER PEUGEOT PROBLEM)
Any suggestions would be very grateful.

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EDC5
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Re: 407 sw overheating

Post by EDC5 »

Sounds like a bit of a nightmare. Do you feel all of the hoses getting hot under the bonnet such as the radiator top hose and heater matrix hose? this could indicate if there is any water flowing. If your top radiator stays cold then perhaps your thermostat is stuck shut.

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white exec
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Re: 407 sw overheating

Post by white exec »

That's a good check to do on the large top hose to the radiator.
The top hose should not get appreciably hot until temp gauge gets towards 85-90C though, which will be around its opening temperature.
An indication whether the water pump is doing its stuff can often be judged by looking into the expansion tank (when not piping hot!), when you should see some swirl/circulation.
If the thermostat is of unknown age or original, just replace it anyway. Not expensive.
Also bleed the cooling system, in case there is an air trapped, which can cause overheating and erratic operation of both 'stat and sensors.

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CitroJim
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Re: 407 sw overheating

Post by CitroJim »

I once knew of a 407 overheating and the cause baffled us for a while... None of the usual suspects...

It turned out to be the water pump... The plastic impeller had fallen off the shaft! The pump was effectively not pumping!

Worth checking if all else seems OK...

trevor.kirton
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Re: 407 sw overheating

Post by trevor.kirton »

UPDATE.
After a lot of cursing at the weekend, we changed the thermostat. Thankfully this looks to have been the problem.
All running at correct Temp.
Many thanks to all that replied with help and suggestions.

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white exec
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Re: 407 sw overheating

Post by white exec »

\:D/