Aux Pump Temp Switch location 1.6jx

[robobobo]

Hello 80-90ers
My aux water pump was knackered and had been for some time. When I fit the new one it is a good pump but the switch is not activating it, works great when I earth it with a jumper from the battery.
So there must be a fault with the switch or earth wire from switch to the pump. My problem is I don't know which switch on the engine is for the pump, I tried grounding the wires attached to all the switches or temp senders I could find but couldn't get the pump to run. I assume that is because there is a fault with the wire or I have missed the switch.
Can anyone tell me the usual switch location so I can double check the wire and switch. I can trace it from the pump as far as the black relay box but no idea where it goes from there....
Mine is a 1988 1.6jx

Thanks for any advice you can give. It’s a fairly unmolested engine as it came to the family at 30k miles so I think the switch would be in its original location .

[clift_d]

The wiring diagrams for the 1.6TD JX are in the wiki here:
http://wiki.club8090.co.uk/index.php/Di ... ine_wiring

Page 83/1 covers the Coolant Circulation Pump wiring - unfortunately the wiring colour codes are not readable in the scan.

There are three coolant temp senders on a JX - one at location 2 in the pic below, and two at location 3 either side of the pipe at that location. If you've tried earthing all the various senders then it may be worth checking the relay in the black wiring box.

[robobobo]

Thanks, great help. I didn’t realised there was a relay involved, thought it was a direct ground to the switch.
Are you the Hackney Syncro man? I have the gold syncro often driving round East London, though its in the garage being restored at the mo.

[robobobo]

Checked the Wiki, all makes sense now. Sorry I hadn’t looked there first, never imagined that info would be there..... note to self

[clift_d]

Are you the Hackney Syncro man? I have the gold syncro often driving round East London, though its in the garage being restored at the mo.

One of a few - I think there a couple of other Syncros in Hackney apart from ours. I think I saw your van about six months ago in Finsbury Park?

[robobobo]

Mine’s been tucked away for a year at a little garage in Lincolnshire, should be back on the rd pretty soon.

[ZsZ]

do you have plastic or metal coolant flanges? They changed them in '88
With early metal flanges the switch should be in the flange at the side of the block (nr 2 on clift_d's photo) although I also saw really early ones with switch positioned in the end flange (pos. nr 3)
the switch itself looks like this:

https://www.brickwerks.co.uk/t3-parts/e ... early.html" onclick="window.open(this.href);return false;

with late plastic flanges it should be one in the side flange (pos 2) a black one. With plastic flanges the in the wiring harness there are additional brown ground wires that is why these senders/switches have two connectors
the switch:
https://www.brickwerks.co.uk/media/cata ... 338974.jpg" onclick="window.open(this.href);return false;
https://www.brickwerks.co.uk/coolant-te ... -late.html" onclick="window.open(this.href);return false;

[robobobo]

That’s great, thanks. It has a metal coolant flange, I’ll investigate this afternoon. I might have missed location 2 so thanks to the wiring diagram and this info I’ll be able to trace the fault. There is definitely something amiss with the glow plug circuit so the two could be related.

[dave friday]

Hi,the water has to be very hot!! Second stage rad fan on hot...and even then mine doesn't come on ( I've checked that the 105 deg c switch does work!)
To check that the switch does work you'll have to put the switch in very hot oil,water in a pan won't get hot enough!
Good luck.

[robobobo]

Thanks everyone. The wire broke off when I pulled the terminal so must have been a crappy connection, when I earthed the terminal it didn’t work but with a new terminal and bridging between the switch body and terminal it runs great. And all glow plugs changed now, starts fine too
Much appreciated