Peugeot Forums banner

1 - 5 of 5 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter #1
Hi all, new to the forum but have done plenty of reading and I don?t mind getting my hands dirty. I picked up a 207 1.4 verve 2009 with the 8v engine on a private sale . It losses coolant sparodically and on some investigation the loss seems to be around the thermostat housing specifically around the return where the thermostat attaches (silver pipe on the pic linked to below) due to the red staining around the area. Since this is not a gradual loss I am thinking that the thermostat is sticking causing pressure build up and it?s leaking at the weakest link which is a rubber pipe with a spring clip.
Since removing the thermostat to test will mean I will have to change coolant and go through bleeding the system I am considering changing the housing and sensor for patern parts for around £70 or possibly original for around £140
What do you think and would you advise any tests or checks before I start spending money. The housing and thermostat seem to be a common failure so changing might be good in the long run.
What I don?t understand it the electrical plug on the thermostat as I thought thermostats were mechanical with wax melting. the sensor on the housing I guess is the temp sensor which hasn?t indicated the car overheating which again is strange.

I have looked for the engine code and can?t seem to find one, there is a number on the block just above the heatsheild that is 10 digits but doesn?t match any listed codes.

This is the housing fitted to my car and there seems to be a number of designs which was confusing but this one looks identical
https://m.aliexpress.com/s/item/32468431277.html?spm=a2g0n.search-cache.0.0.7f25570fLvIbsh

Thanks

Sully
 

·
Registered
Joined
·
165 Posts
Welcome to the forum,

I was loosing coolant too from around that area, but when i investigated I found that the whole housing was weeping coolant and I removed it.cleaned up the mating faces and applied new silicone.
The hose you think is leaking contains an 'o' ring but I drew a blank attempting to get it separately from the housing.
The sensor on the thermostat feeds the ECU with engine temperature.
Getting the plug off that can be tricky and it needs releasing by pullling a release up. I wasted half a day trying to figure out how to remove it :(
the brass allen key on the housing is a Bleed for the cooling system. and this would be my first port of call as TU engines are notorious for air locks. make sure you bleed this engine correctly
easiest way to find your engine code is through your VIN number.
 

·
Registered
Joined
·
3 Posts
Discussion Starter #3
Stvstx thanks for a quick reply. Do you think bleeding code fix the coolant loss. I did open the coolant cap slowly after a steady 40mile motorway run and the coolant was on max but it started rising quick so I closed the cap again. There was a fair bit of pressure in there and I have not seen a car do this before, normally you get a hiss from the pressure release but no rising of the coolant.
Looks like the bank holiday will include so investigations

Sully
 

·
Registered
Joined
·
165 Posts
removing the cap from a hot engine is not good practice as the increase in pressure delays the boiling of the water to a higher temperature.
when you remove the cap from a hot engine the coolant will boil. and hence the increase in volume.
Air expands more than water with temperature so you could have a partial air lock causing it to over pressure. it should by design exit via the coolant cap.
bleed it a few times and see if that helps (cold engine and a suitable bottle with the base removed and upside down on the reservoir)
Filling with antifreeze and DEIONISED water only.

Note: once you have ruled out all other avenues all that remains is the head gasket.
 

·
Registered
Joined
·
3 Posts
Discussion Starter #5
I guess so but never seen anything like it on previous cars, will have a play at the weekend. Will get the local garage to do a sniff test to check for hydrocarbons in coolant. I am sure a pressure test would come up clean as the system clearly holds pressure

Will report back on my finding

Sully
 
1 - 5 of 5 Posts
Top