1972 100GL 1.9 - Sticky thermostat or temp sender?

[j0hn]

Hi,

I've just got myself a 1972 100GL with the 1.9l engine.

The temperature gauge readings seem to be a bit erratic at times - sometimes after 5 minutes of driving the needle will be right up to the red mark, and will creep up ever so slightly when sat in traffic - but it's never boiled over etc. Other times the temps will gradually rise as normal up to the mid point and never go above that - it will reduce if travelling at cruising speed on dual carriageway etc.

Is this likely to be the thermostat or a dodgy sender? Even when it's playing up the gauge still moves about depending whether you're cruising or around town. Sometimes it will be up in the red until I stop and shut off for a while, then when I get back in the gauge goes back to normal.

Any thoughts/advice greatly appreciated.

Cheers,

John

[missfire]

Hi, don't know but you can check both in a pan of water, bring the sender up to temp. gradually measuring resistance, and themostat also, check if it's openng correctly/enough, compare to whatever the spec. is. I'd think more likely electrical related as thermostats tend to jam open when dodgy don't they?

[j0hn]

Originally Posted by missfire

Hi, don't know but you can check both in a pan of water, bring the sender up to temp. gradually measuring resistance, and themostat also, check if it's openng correctly/enough, compare to whatever the spec. is. I'd think more likely electrical related as thermostats tend to jam open when dodgy don't they?

I've had a couple of short runs out in it this week, and it seems to be behaving itself now - it may just've been some gremlins from not being used very much for so long. I'll keep an eye on it and test the sensor and 'stat if it starts playing up again.

Cheers,

John