Coolant Temperature Guage Fault

[Ian Hulley]

I was wondering if some kind person could tell me where the earth is for the coolant temp. guage is (1989 late DG) ?? One day it works the next it doesn't .... then recently nothing AND then the other day the low-level light flashed even though the header tank was full (and the top-up tank was still on 'max' too ) . Made me think it was an earth issue ?

IF it's the one on top of the left bank of cylinders then I replaced it yesterday with no result Perhaps its the sender itself that's up the duff ? The engine's not getting over-hot or anything but I'd like to sort it.

Cheers,Ian.

[BiC]

Ian,

I've recently bought a 1989 T25 deisel 1600cc van with exact same problem. The good folks on here have suggested many diffrent things as its quite common. Here's a link:

http://www.club80-90.co.uk/forum/viewtopic.php?t=7203

Anyway, I cleaned the contacts and the sensor in the top tank (by the battery, in the engine bay) to no avail. The water was on max level on the top-up tank, behind the rear number plater but the lamp still flashed whenever it felt like.

Eventually realized that the sensor needed to pass through the water to form a circuit - the water level was too low in the top tank so I poured a cup full in and hey presto, problem solved.

Now, guys, is it OK to do this i.e. top up the level in the upper (engine bay) tank?

[Ian Hulley]

Hi BiC (and welcome to the club) the DG (and by the sound of it the diesel ?) has a top-up tank which 'should' feed the header tank by pressure/vacuum,it's not uncommon for the caps to be duff. It's the sensor or earth on the thermostat housing that's (possibly) tatered on mine,I think

Cheers,Ian.