MattF or anyone

[POPEYE]

I've been busy with me pencil and wonder if anyone (or matt) who knows a bit about circuits would cast your eye over the drawings i did, just to see if they'll work and if i missed anything, the first one is for the four cooling fans,
sorry there not up to proper electrical drawing standard but i understand em like this, i've been racking my brains over useing the trucks fan sensor but as it's permantly earthed and turns the fan on when the earth is broken i just cant figure it out, so i'm thinking of useing a couple of the C P C thermostat switches ( two? belt and braces) fixed to the top hose, useing two 70amp relays, one for the front fans and one for the lower fans, plus a second pair of 70amp relays so i can switch em on manually, through a 3 position switch, center "off", switch up for stat controll and down for manual "on" the stats switch (open) at 90c and reset at 75c, i've taken a feed for the led indicators as you can see so i get indicator when the fans come on,
The other two drawing are for intercooler fan and water pump, similar (but simpler) to the first drawing, the pump however i'll need to come on when the engine stat opens so i need to know what temp it opens at please,
hope to christ you can understand em and wot i'm on about, do ya think they'll work? have i missed owt?
Cheers all, Ian

In case anyone wonders WTF i'm talking about, the above was posted before the site went down, i've deleated the old drawings and and decieded to just have two fans on the front, the drawing below works just fine, if anyone wants to "up grade" their cooling back up fan you can adapt the drawing to run one fan, gives ya off altogether, auto (comes on when the engine reaches temp) or on manually, also on auto it will run on after the ign's switched off, untill the temp drop's below the sensor's setting,
Thanks to matt and the guys below for the help,

[Peachperformance]

hi, well it looks like it would work, although you could simplify it depending on how you are wanting the fans to run. It's just and idea but how about making the fans fully automatic but still having a manual override switch.

So you give your two "auto" relays terminal 85's an ignition feed. Ditch the two "manual" relays completely, and connect a second earth feed to the "auto" relays terminal 86's which runs through a standard "on/off" switch. This way the fans would run automatically (as long as the ignition is on) but you could also control them by earthing terminal 86 via your on/off switch.

The same idea would work for your other 2 circuits.

I can't help you on the fuse ratings though as I don't know the current draw of your fans.

[Apache]

Ian, with that many fans, surely you're building a hovercraft rather than a Surf!?

[nero279]

hi, well it looks like it would work, although you could simplify it depending on how you are wanting the fans to run. It's just and idea but how about making the fans fully automatic but still having a manual override switch.

So you give your two "auto" relays terminal 85's an ignition feed. Ditch the two "manual" relays completely, and connect a second earth feed to the "auto" relays terminal 86's which runs through a standard "on/off" switch. This way the fans would run automatically (as long as the ignition is on) but you could also control them by earthing terminal 86 via your on/off switch.

The same idea would work for your other 2 circuits.

I can't help you on the fuse ratings though as I don't know the current draw of your fans.

I agree, only reason not to do this would be if you want a manual override which turns them off, the only reason i can think you would want this is for wading.

Other than that looks good to me Ian. Confused as to the water pump though, is this for the main cooling system? Have you converted it to an electric pump or something? I think the standard stat is 88 degrees but it might be 82, i'm sure matt had researched them with a view to using a lower temp one from a corrolla or something.

[POPEYE]

Cheer's for the replys, Matt sent me a corolla sensor and was going to do a drawing for me but guessing he's busy and i dont want to keep asking, the corolla/surf sensor is perpantly earthed and switches the fan when it breaks the circuit (or you remove/cut the wire) and i could'nt work out a circuit useing this sensor so thats the reason for the thermostat switches from CPC
their general use switches used for any number of things from electric kettles to c/h cylinder temp control, the reason i was thinking of useing three position rocker/toggle switches is it would give me the options of off (center position) stat controll, (up position) or manual on (down position) also useing battery supplys and switched to stat (position) that would let the fans run on after the ign is switched off (like other cars), I'm as paronoid as matt used to be
The water pump is not replaceing the engine's manual pump, just assisting it (i hope), i've fitted a second rad where the AC rad used to be and with the extra pipework thought the pump might help, it's 24volt (all i had) but i tryed it in a bucket of water and it pumps good on 12volt it's all trial and error at the mo and may well have to revert to the standard rad set up, we'll see! anyway if i use another stat switch same as the cooling fans with a setting of 90c on and 75c reset that should do it, engine should'nt go under 75c too often so the pump will be on most of the time,
The extra fans may give me a bit of lift Andy, offset the weight of the bull bars a bit

[marky]

DELORION TIME MACHINE wiring diags

[wishbone]

I'm pretty sure you can use a single pole, double throw relay with the original temp sensor. It had an extra terminal so you can choose whether to have output when the coil is 'on', or output when off. Set it up so when the sensor breaks the earth, the fans come on.

Rob.

[Peachperformance]

Yeah I've been thinking about that.

Durite make a 70amp "changeover" relay. It has your normal 85, 86, 30 and 87 terminals but also has an 87a terminal.

When there is no signal feed down T85 the relay is switched to the position that whatever feed (+ or -) is on the T30, is output down T87a. When a feed is then sent down T85 the relay switches the feed to T87 (same as a normal relay).

So if you connect your output from the Hilux fan sensor to T86 and connect your fan relays to the 87a terminal, they will come on when the Hilux sensor breaks the earth to T86.