Radiator cooling problem.

[jameshearn]

Hello.
Can anyone advise please?

The temperature on my 1996 smiley 2.5di has been erratic in the last year or so - although never hitting the red zone.
Prior she always sat in the middle of 'normal' - so I know the change and movement of temp is a sign of something.

Anyway, I am not losing coolant and the fan works fine.

I have changed the thermostat in the last week, thinking it was that - I am also flushed the coolant about 3 weeks ago.

Now, the engine heats up and sits about 3/4 - so around the 'A' & the 'L' of the normal range i.e. not in the middle.
And to be fair it stays there, but it's not how it used to operate and leads me to think it's operating at a higher temp than it should.

The hose from the thermostat housing to the radiator is very hot, as in the right side of the radiator (as you're looking into the engine).
The left hand side of the radiator and the bottom hose are very cool, nowhere near the other side and hose.

Is this the reason for the higher than normal temp?
Is there is blockage/air lock in the left hand side of the radiator?
Do I need to flush the radiator?
Do I need to flush the cooling system again, seeing as I changed the thermostat recently?

The blowers in the can blow hot air as normal, so that's fine.
The coolant level does not drop, there are no visible leaks.

Any advice would be valuable and I am scratching my head and thinking of flushing/replacing the radiator.

Many thanks.

[Jim Archer]

Take it for a drive enough to get it fully up to temperature, then feel the left side of the rad/bottom hose. It should be hot-ish, and will cool suprisingly quickly at idle. At idle the outlet hose will always be cold compared to the inlet unless is blocked in the rad - then you can feel which tube runs are doing the work.

There is a gauge check/calibration (I think) using a resistor, but the easy way is to just ground the wire to the sender and see the gauge reads Max. I think there is also a way to check the sender, but don't quote me.

As a engine, DIs do like to run nice and toasty hot.

Jim

[jameshearn]

OK thanks for the reply Jim.
I felt the bottom hose yesterday after the van had got up to a driving temp and it is was very cool - but the bizarre aspect was that the whole left side of the radiator was cool also and the right side hot, or is that normal also?
I am pretty sure the temp sensor and gauge are working fine though, because the gauge rises steadily upto a driving temp and a little beyond based on previous experience of owning this van.
And if I were to turn on the cab fans, full heat, then the temp gauge starts to decrease slowly.

I am tempted to flush the system again, take off the rad, flush that with a hose pipe several times and then reattach and refill.
My gut is saying the ad is blocked.

But I am not experienced enough to know.

I don't like hot running engines, I fear for the head gasket!