Well from that I'm not sure John? given that I'd assume 2 meters of cable that's around 0.06 resistance, and given that that chart shows that less than 0.2 covers a range of 70-100 (30)deg, then a 2 meter length of cable = 30 / (0.2/0.06) = 9 deg C. Ok wouldn't throw figures totally out of the ball park, but still a measurable difference.
However given my knowledge of electronics and maths is limited, this could all be bollocks
as the sensors work on resistance, and its change with temperature, then the length of the wire between the gauge and the pan of hot water could offset the reading, as any wire has a resistance. https://chemandy.com/calculators/round-wire-resistance-calculator.htm But it is very low! This online calculator suggests that the Ohms in a meter of typical wiring wire (0.5mm^2)are 0.03.
So you would need to be heating the pan in the kitchen while the car was in the garage (10 meters of wire?) to get near the change in resistance of a typical sensor. See below
I like mine, which is in a combined oil-pressure/temperature gauge unit. It is accurate, responsive and calibrated in ºC. It is a bit of a pain to work with though as the whole thing has to be removed as a unit and the capillary is somewhat fragile and needs to be treated with respect. I've also never managed to get it properly backlit as the one I have is designed for external lighting and a thin (<3mm panel mount). Originally MG I think?
From what I have read the way to go about setting up the electronic (non capillary) type, is to get a couple of senders and bench test them with the gauge and a pan of water that you can bring the temperature up in, and thus find the sender that works well with the gauge. I have also read that its a good idea when doing it out of the car to use a length of wire connecting the sender and the gauge of about the right length & gauge as that in the car between the two.
Yes, thanks Nick and John for your replies.
I might go for this type of gauge on my Dolomite Sprint,
given that the feedback I have read suggests that the senders currently available available are quite hit and miss.
The one thing putting me off the idea is the probably that fitting such a gauge could make removing the instrument panel more complicated?
Also I do prefer the appearance of the original Dolomite gauges!
Can't remember which way up mine are offhand. Will shuffle out and have a look later.
I do know I had to make some longer ones to get the bonnet to sit right. There are many possible reasons for that though given the, err, varied, provenance and condition of the parts used in the build.
Ah see your confusion about 121254, Work shop manual shows slots at bottom, parts diagrams show slots at top. Have no idea which is correct, but at bottom does make adjustment easier and looks right to me.
No need to apologise about being in Exeter
The slots should go to the bottom.
NB when given a brand new factory bonnet (many decades ago) I had a similar problem getting decent alignment (and still isn't perfect today with either of my bonnets) I found I had to extend the slots to get it close (in fact I made a new set of stainless ones so had oodles of adjustment) now I find I can remove and refit or even swap between the bonnets and it drops back just about right (provided I line up the pop marks I made when I had it as I wanted it).
Just found this site - Iam in Exeter with a 1971 mk2 vitesse convertible stuck on bonnet alignment cannot obtain 5 to 8 mm gap to screen as per the manuals , with all the queries as to which way should the links 121254 be fitted slot to the top or or to the bottom fixing .
Just read you changed /fitted yours - did you get the gap correct , if so slot to top or bottom ?
Iam a member of Club T too old now to be competitor any more.