Dougalo 0 Posted January 25, 2006 The oil temp on my 91 valver rarely shows even after a long journey - even then it never gets above 60. Also the normal temp gauge never goes up as far as it should - usually sitting no more than 70. Are these connected? and what is it likely to be? Cheers Quote Share this post Link to post Share on other sites
flusted 0 Posted January 25, 2006 my water temp is always low this time of year,but even with an oil cooler,my oil reads 70 in about 10mins Quote Share this post Link to post Share on other sites
bcstudent 0 Posted January 25, 2006 My 1.8 16v runs at 90 degree water temperature all year 'round. Like flusted, I see 70 degrees oil temperature after a short time and a max. of around 100 degrees (with no after-market oil cooler). As far as I can see, the only link between the oil temperature and water temperature senders is the earth. I suspect that the senders operate with a negative temperature coefficient (resistance decreases as the temperature rises), meaning that extra resistance introduced through a poor earth connection would make the associated gauges read low. It's just a theory, but it seems reasonable enough. Plus, cleaning up earth connections in the engine bay is free! Quote Share this post Link to post Share on other sites
davidwort 0 Posted January 25, 2006 My 1.8 16v runs at 90 degree water temperature all year 'round. Like flusted, I see 70 degrees oil temperature after a short time and a max. of around 100 degrees (with no after-market oil cooler). As far as I can see, the only link between the oil temperature and water temperature senders is the earth. I suspect that the senders operate with a negative temperature coefficient (resistance decreases as the temperature rises), meaning that extra resistance introduced through a poor earth connection would make the associated gauges read low. It's just a theory, but it seems reasonable enough. Plus, cleaning up earth connections in the engine bay is free! wobbly earth connection on head gave wacky high readings on mine??? Quote Share this post Link to post Share on other sites
Dougalo 0 Posted January 25, 2006 where is the earth connection on the head? excuse my ignorance! Quote Share this post Link to post Share on other sites
STORM 2 0 Posted January 30, 2006 where is the earth connection on the head? excuse my ignorance! is it next to the rear engine mount? I'm notsure ...anyone? Quote Share this post Link to post Share on other sites
Dougalo 0 Posted February 6, 2006 where is the earth connection on the head? excuse my ignorance! Anyone? Quote Share this post Link to post Share on other sites
ardandy 0 Posted February 6, 2006 Under the bonnet! That about sums up my mechanical knowledge. Really should do a course! Quote Share this post Link to post Share on other sites
STORM 2 0 Posted February 8, 2006 The oil temp on my 91 valver rarely shows even after a long journey - even then it never gets above 60. Also the normal temp gauge never goes up as far as it should - usually sitting no more than 70. Are these connected? and what is it likely to be? Cheers both the wire from the oiltemp sender on the oil filter housing and the wiring from the water temp sender on the head thermo housing run TOGETHER to the cylindrical loom just heind the aux water pump. A common problem with age is a leaky aux pump. When it leaks it can get into the cylindrical loom and cause a LOW/ --- MFA OIL TEMP and crazy water temps. So check this large cylindrical connector for corrosion. Quote Share this post Link to post Share on other sites