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MG Midget and Sprite Technical - Electric fan switch temp

I have fit a electric cooling fan with a adjustable fan temp switch which has a sensor in top hose but it comes on to early, temp not even at N on gauge so i am going to fit a switch in the top hose they have 2 switches 95 deg and 88 deg but not sure which to get for a 1500
mark (1977 1500 Midget) Preston Lancs

Gday Mark
So even at it's highest setting the "adjustable fan temp switch" comes on too low?? It may be faulty, it should be adjustable to at least 95C IMHO.
I fitted a fixed 185F (85C) switch in the rad near the overflow pipe. It comes on as a matter of routine when warmed up (winter) when I pull up at the lights. My thermostat is a 185F. I'll probably go up, say to 92C, for summer. 95 is a smidgeon to close to boiling for my liking. HTH If you want a picture just ask, I can post this say later today local time. Cheers Rod
R W Bowers

have a look at this site, http://www.cbsonline.co.uk/search,b.html?q=fan+switch they have a good selection..
ive got the 87/82 deg one, .. makes contact at 87deg, then breaks at 82deg... works well for me..
however mines a datsun engine, the temp you chose will also be effected by your thermostat, you need the fan temp switch to operate at higher temperatures than your thermostat.
Andy Phillips (frankenfrog)

Mark,
I'm with Rod if the switch is adjustable then it should be within range and need setting just a bit higher temp

I wouldn't worry about the temp on the gauge getting exactly to the 'N' on the gauge as long as it's fairly near as the gauge may be inaccurate

on the 1275s the needle on the gauge often is well before the 'N' when moving

if your 'water' cooling is good you should also consider that if you have an oil cooler fitted then this is often over cooling your oil unless you have an oil thermostat fitted
Nigel Atkins

it is set at full and comes on before the gauge reads N keeps it mid way before the N .I have an oil cooler with a thermostat fitted
mark (1977 1500 Midget) Preston Lancs

your first post (like most of my posts at anytime) I found a little confusing as to what you intend to do but that's me

(on my 1275) I've got a Revotec fan kit with the thermoswitch spliced into the top hose, the numbers are far too small to see so I can only say it's set to a gnat's whisker before 6 o'clock and keeps my temp gauge showing just below N when it cuts in and well before N when it cuts out

I could have the switch cut in a lot earlier or lot later
Nigel Atkins

Hi Mark, a postscript, I fitted my thermo switch away from the top hose/thermostat area (next to the expansion hose) to prevent early triggering. The aim is to switch the fan on when the water in the radiator, not the top hose, reaches the set point, which works fine for me. HTH Rod

R W Bowers

Choice of fan switching also needs to relate to which thermostat you are using.
Guy W

I am trying a 92 deg switch and will see how that is fitted in the top hose, thought about fitting in the side of the thermostat housing where there is a blanked off hole on the left hand side .
mark (1977 1500 Midget) Preston Lancs

This thread was discussed between 16/06/2013 and 23/06/2013

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