Mr Polson 10,214 Posted April 19, 2013 So I'm wiring in EF thermos in my ute on the weekend. Noticed during the week driving it without the clutch fan on, temp was fine unless I had to sit and idle for any amount of time. So this got me thinking, rather than wire it up to a sensor and do it that way, is it the same principle to wire it to a switch, where the switch just completes the circuit for the thermos, and they turn on/off. Now for the tricky part. I have a ZL dash in my ute, and part of the ZL dash is a switch for a rear demister. Utes don't have rear demisters, so I was wondering, can I use the wiring and switch for the demister? Bonus to this is the light in the dash to remind me that the fans are on. I figure all I have to do is find the wires for the demister, and add in the positive and negative to the demister circuit? Share this post Link to post Share on other sites
Thom 6,650 Posted April 19, 2013 Should be pretty easy, negative shouldn't matter as long as there is a earth on the fans and the relay, at worst all you have to do is run a switching wire to the positive side of the relay and the demister switch easy as Share this post Link to post Share on other sites
ZL. 19 Posted April 19, 2013 I wired my thermos up to a on/off switch before i got the temp switch, didn't have to run em on the highway just when i got into town,But after a couple of times of forgeting to turn it on, you soon appreciate the value of a temp switch. Share this post Link to post Share on other sites
Gav 616 Posted April 19, 2013 Is this just for the short term Polson? For the long term, go automatic function, go the thermostatic switch - you don't want to spend the time you drive consumed by thoughts of the needs of your car's cooling system - let a gadget do that for you! Share this post Link to post Share on other sites
XBTAS 76 Posted April 19, 2013 The switch you got with the thermos should do the job mate. Share this post Link to post Share on other sites
hendrixhc 10,920 Posted April 20, 2013 Manual switch is fine but why bother? Using the auto switch you dont have to think about it and it will just by itself as required. Share this post Link to post Share on other sites
Mr Polson 10,214 Posted April 20, 2013 Manual switch would let me decide when to turn them on rather than they come on when not really needed. I've been driving around all day today with no fan on at all, and no sign of overheating. Share this post Link to post Share on other sites
BBS XE 160 Posted April 20, 2013 Here's a basic diagram for what you want to do Chris. Nothing wrong with switching it yourself, just don't forget! Add a fuse between the relay and the fans for safety's sake. 1 Mr Polson reacted to this Share this post Link to post Share on other sites
Mr Polson 10,214 Posted April 20, 2013 That makes sense to me, any idea what amperage the fuse should be? Share this post Link to post Share on other sites
Ants 6,370 Posted April 20, 2013 I ran the auto switch in the ghia and it worked fine. Share this post Link to post Share on other sites
GspecZL 979 Posted April 20, 2013 In the ZH the previous owner set the thermos up with auto, manual and off functions. I would just go auto myself. Share this post Link to post Share on other sites
Crazy2287 1,886 Posted April 20, 2013 start with 35 amps... 2 Mr Polson and mcfly94 reacted to this Share this post Link to post Share on other sites
XES 859 Posted April 20, 2013 start with 35 amps... Good idea here. I had a 30 amp circut breaker in mine and it kept cutting out. Switched it out for a 35 amp fuse and haven't had any issues with it since. Share this post Link to post Share on other sites
Gav 616 Posted April 20, 2013 Ford uses a 60 amp fuse from the factory...so do I in both cars I've done this to...with no dramas. If your worried about the fans coming on when you don't want to use the Davies Craig variable switch...cost me around fifty bucks from Supercheap i think - you can set it as high or low as you want to. I set mine after trial and error and they come on the temp gauge reaches middle range. There are probably more scientific ways of setting the fans to come on appropriately...but it's a work in progress. Share this post Link to post Share on other sites
gerg 10,871 Posted April 20, 2013 Better check what alternator you're running too. You don't want to overload it, particularly at idle when you need the fans on but it charges the least. I ran mine on a dash switch for a while and it gave me the shits. Trust me, a temp switch means one less hassle while driving your beast. Share this post Link to post Share on other sites
Mr Polson 10,214 Posted April 20, 2013 For now a manual switch would probably be temporary, or only last as long as the xflow is in there. Alternator at the moment is standard, I have a higher amp carby one and an EFI xflow one. Guess I'll see which one copes the best. Share this post Link to post Share on other sites
hendrixhc 10,920 Posted April 20, 2013 You could always use the circuit above and parallel an auto switch with the manual switch. This would allow them to run automatically and if you required them to run for any particular reason you could manually bypass. 1 Mr Polson reacted to this Share this post Link to post Share on other sites
Mr Polson 10,214 Posted April 20, 2013 That's a good idea, would also mean I can easily add in the auto switch later. Share this post Link to post Share on other sites
BBS XE 160 Posted April 21, 2013 Sorry I didn't reply sooner re the fuse amps, I'd start with 35 amps as said above. Share this post Link to post Share on other sites
Mr Polson 10,214 Posted April 21, 2013 Got them wired in today, just hooked up to the manual switch for now (running via the demister as I wanted), will look at adding a temp sensor a bit later on. Also managed to get them in without having to chop up the thread for the original clutch fan from the water pump. Wiring at fans Relay looks almost factory No interference from clutch fan thread 1 LTD083 reacted to this Share this post Link to post Share on other sites
adrianphu123 73 Posted April 21, 2013 This thread kind of got me thinking of doing this conversion myself. What about something like this? http://www.ebay.com.au/itm/PAINLESS-WIRING-FAN-THOM-II-ELECTRIC-FAN-RELAY-WITH-THERMOSTATIC-SWITCH1-PW30103-/181092254994?pt=AU_Car_Parts_Accessories&hash=item2a29f08512&_uhb=1#ht_2834wt_1205 Share this post Link to post Share on other sites
Mr Polson 10,214 Posted April 21, 2013 This thread kind of got me thinking of doing this conversion myself. What about something like this? http://www.ebay.com.au/itm/PAINLESS-WIRING-FAN-THOM-II-ELECTRIC-FAN-RELAY-WITH-THERMOSTATIC-SWITCH1-PW30103-/181092254994?pt=AU_Car_Parts_Accessories&hash=item2a29f08512&_uhb=1#ht_2834wt_1205 Don't see why it wouldn't work, but imo is a bit pricey... I paid $50 for my whole conversion (thermos and relay switch). Then I paid $15 total to get a normal relay rather than the temp one that came with the thermos, and for an inline fuse holder for the 12V direct feed from Autobarn. Used wiring from an old wiring harness that was lying around, and to connect two wires into one and vice versa the factory splitters that are in utes for towing wiring. Share this post Link to post Share on other sites
BBS XE 160 Posted April 21, 2013 This thread kind of got me thinking of doing this conversion myself. What about something like this? http://www.ebay.com.au/itm/PAINLESS-WIRING-FAN-THOM-II-ELECTRIC-FAN-RELAY-WITH-THERMOSTATIC-SWITCH1-PW30103-/181092254994?pt=AU_Car_Parts_Accessories&hash=item2a29f08512&_uhb=1#ht_2834wt_1205 Yeah that's too dear, be cheaper to buy the parts seperate. Get most of it at Jaycar cheaper. Share this post Link to post Share on other sites
gerg 10,871 Posted April 21, 2013 Polson those white connectors wouldn't happen to be scotch-locks at all would they? If so, banish them to hell! They are the root of maybe 90% of all problems on trailer wiring. They are pure evil. 1 Ando81 reacted to this Share this post Link to post Share on other sites
Mr Polson 10,214 Posted April 22, 2013 Polson those white connectors wouldn't happen to be scotch-locks at all would they? If so, banish them to hell! They are the root of maybe 90% of all problems on trailer wiring. They are pure evil. Umm, maybe? They're only temporary, it was all I had lying around. I'm yet to have trouble with them in my trailer wiring Share this post Link to post Share on other sites
