Club 80-90 Forums

Hi All!

My temp needle usually sits dead centre when up to temp, however, after a long run today it is currently sitting just after the white marker as per the photo:



The heater in the van is working normal too - nice and hot. I've tried putting the fan on full when the lever is both on hot and cold but it doesn't really make any difference to the needle position.

I changed the sensor about a year ago and as said, temp has read perfectly normal until today.

Any ideas appreciated.

I had the very same thing, and as you said it was stuck open. New stat required

I could be talking from my rear, but I suppose it could be a poor earth, or another electrical issue?

The temp gauge is fed via 10v from the voltage regulator, and then depending on resistance to earth via the sensor, the gauge moves.
So if the path to earth is not `good` then the temp could read cooler than normal.

I assume the fuel gauge reads as expected? If so, the voltage regulator will be OK.

Something to think about if the stat proves ok, anyway.

Many Thanks for the replies chaps - fuel gauge works fine although I have had another thought. She's been running a little lean and have just sorted the timing and co2 on a gas analyser as it was running at 1.2 and is now 2.7. Do you think it's possible the leaness could have caused it to run slightly hotter and that it has gone to around the correct level now that's been sorted?

Just thought I'd throw that one out there!

300CE wrote:Many Thanks for the replies chaps - fuel gauge works fine although I have had another thought. She's been running a little lean and have just sorted the timing and co2 on a gas analyser as it was running at 1.2 and is now 2.7. Do you think it's possible the leaness could have caused it to run slightly hotter and that it has gone to around the correct level now that's been sorted?

Just thought I'd throw that one out there!

No faulty guage or thermostat IMO.

Nice one cheers for confirming Paul

Can it cause any problems whilst it's waiting to be changed?

1.2 isn't particularly lean, and it's only at idle. Mixture at revs/under load isn't adjustable (except by changing jet sizes) so it won't be that affecting temp gauge reading. More likely is slight corrosion on connector to sensor causing higher resistance.

300CE wrote:Nice one cheers for confirming Paul

Can it cause any problems whilst it's waiting to be changed?

Unlikely.

your stat oens at about 85 degrees C, this is uncomfortable to touch, get it hot open the hatch and feel the pipes in and out of thermostat housing.
Best temperature guage you can find are your trained fingers, if you can hold your hand on something for a while its no more than about 50 deg C.

Thanks again gang - will try the feel test Paul. Thermostat is about 3 years old so will get it changed and will also check and clean the prongs on the sensor too.

I'm going to go for a dodgy sender.
I have had to replace mine 3 times in the last four years or so.
Not sure why, I ain't buying cheap nasty JK ones either.
Fixes it every time.
Worth checking the stat isn't stuck open though.
Mind you, you can tell if a stat is stuck open because it takes considerably longer for the gauge to start to move up.

I'm guessing 1986 is a late cooling system like mine with plastic thermostat housing?

To test the wiring , could the OP just pull off the connector and short both wires the watch needle go over to hot?
That should at least prove the circuit ( apart from the temp sender )

ghost123uk wrote: Not sure why, I ain't buying cheap nasty JK ones either.
.

Probably because nothng is made to last 30 years anymore.
Mine is origional, as is the thermo switch.

Some people replace stuff thats not broken just because they think new is better, it's often not.

Cheers for the input everyone - i'll try the easiest first and provide an update once it's all back to normal