[Engine] 2hdi engine temp issue

[Roadie]

Hi,
I have an issue with my Partner 2hdi, the engine temp gauge reads approx 82c most of the time but will drop back to 70c for 10mins or so & then back to 82c.
Occasionally it will suddendly jump into the red & the stop light on the dash comes on, then within 30 seconds it'll fall back to 82c. Once when this happened I stopped ( engine off ) quickly to check, the top hose was warm & the rad fan was running, then the top hose got hot & on re-starting the temp was 82c.
The water pump was replaced 4 weeks ago along with the timing belt when I first bought the van, so don't know if this was happening before that.
I've replaced the thermostat but that hasn't made any difference.
I wondered if it may be an air lock, but I can't find any advice on bleeding the cooling system, opening the bleed valve on the thermostat housing releases coolant but no air.
The heater works OK.

Any ideas ?

Many Thanks.

[polar]

could be an air lock - need to find the bleed points usually on the heater pipes as they go though the balk head.

could also be the temperature sender telling lies - i have a known them to do this.

[ddb]

Top hose should be far too hot to grip if fan is running.

[Jed Clampit]

The other thing you need to check is the radiator it self also the cap on the header tank for seal

[Roadie]

Thanks for your ideas, I'll have a play this week-end if I have time.

[Roadie]

Thanks for your ideas, I'll have a play this week-end if I have time.

I bled the cooling system using a temp. header tank extension ( pop bottle ) to increase the height of the coolant level, a little more air bled out & I thought this had fixed the issue.
Then 2 days later the problem re-occured.
I've now replaced the coolant temp. sensor & it's been OK for a week, but I have used the van only a few times, however once warmed up the gauge sits at 82c & stays there, so far so good.

[Roadie]

All Sorted ! 

It was the coolant temp. sensor.     [Image: biggrin.png]

[polar]

Was the hosing plastic of aluminium?

[Jed Clampit]

Good to see it sorted ant not to much money  the kind i like to see happy day's