hotting up

[tomk]

My 325 touring temperature gauge has recently started to creep up over the half way point when in traffic up to about three quarters. It seems fine on open roads.

Is it time for a new radiator (the existing one looks very tired)or is it some other problem?

I've flushed the system and the original water looked all clean, not rusty etc.

Any ideas?
Thanks

[bobbin1982]

water pump maybe

[tomk]

Thats a possible, hasn't been replaced for 50,000 miles. But the radiator is even older!

[Brianmoooore]

It's normal for the temp. to go up slightly in traffic, but not by much.
When driving at normal speeds the forward motion of the car provides sufficient airflow through the radiator, but in traffic this function is taken over by the engine driven fan.
This fan is coupled to the water pump by a viscous coupling which normally allows the fan to free wheel, but locks up when it detects hotter than usual air coming from the radiator.
This lock up doesn't seem to be happening in your case, so the viscous coupling has probably failed.

[tomk]

Thanks Brianmoooore, Will have a look in the Haynes manual as need some more info.
What's required to replace?

[Brianmoooore]

One viscous coupling and a 32mm open ended spanner.

[daimlerman]

Fan unit has a reverse or left hand thread....to remove it belt your spanner the opposite way to normal!
Draper make a special 32mm spanner correctly shaped for this job.

[tomk]

brilliant thanks guys.

[mrLEE30]

if your water pump is 50,000 miles then your timing belt will be of similar age most likely, while you have the fan off i would change the cam belt, waterpump and tensioner, can be done with average home tools and average home mechanic

[TPS]

I did the job once, so it must be simple!