I was warned that the engine had a tendency to overheat in
traffic, and also that the water needed filling up regularly. The previous
owner had fitted an override switch to the fan to get around the problem. He
has also removed the thermostat in case that was not opening fully. As a
result the car was very slow to come to working temperature, worked nicely while
still moving but heated up if you were stationary. I thought this was a bit
odd, as there was a thermostatically controlled switch in the radiator that
should have turned the fan on long before the override switch was turned on.
As this system was perfectly usable I left it alone
initially, filling it up every couple of weeks. It is rather an odd design in
that you fill it up via the expansion bottle. However, on 3 occasions I noticed
water coming from underneath after I returned from a trip and decided it must
have a leak somewhere. But further investigation showed the water was coming
from the overflow pipe from the expansion bottle. To make sure I installed an
‘expansion’ bottle to the ‘expansion’ bottle and ran it with the overflow tube
into the new bottle. Not one of my better plans as after about 15 minutes I saw
water cascading into the passenger footwell. Turned out the new expansion
bottle had quickly filled and overflowed as well.
It was after I had refilled it from this incident that I
found part of the problem. I had done up the pressure cap on the expansion
bottle to what felt like full tight, but on this occasion I decided to make sure
and by applying more pressure I managed another quarter turn. Since then no
water leak.
A test of the original thermostat showed it was probably
seized, so a new one was purchased off E-Bay.
I then found that shorting out the thermostatic switch made
the fan run, so decided the switch was broken. The general advice on the forum
was not to try and replace it, as apparently it was a poor design (not screwed
in, but a bayonet fitting) and incredibly difficult to seal a new one. So I
decided to buy an after-market adjustable thermostat switch and fit that.
Status: Thermostat and switch awaiting fitment.