Whoops- there's no drain tap

[Chevron Terry]

Iam just about to drain the coolant , fit my new thermal rad switch and refill with new Antifreeze .
Big problem ! !
the tap to drain the rad is missing or broken off .
Any body got any ideas around my challenge ?
Hopefully not a new rad .
Terry .

[CitroJim]

I've used two methods in the past Terry, either pull off the bottom hose or unbolt the water pump.

If your rad has the bayonet connectors, the first method is hard to do and not recommended. The second is only really useful if you are doing a cambelt/waterpump replacement.

However, if you follow the bottom hose back to the block, it's held onto the water distribution manifold with a more normal spring clip and this is the best and easiest point to disconnect the hose. It'll be messy but then even with a drain cock, draining coolant always is.

Some aftermarket rads don't have a cock, presumably to save costs It might save costs but it's annoying...

[Chevron Terry]

Thanks citrojim .
Job is now done . but can you tell me at what temp , the electric fan cuts in ?
The engine reached 100 , and still the fan didnot cut in .
Would it be the thermostat ?
many thanks
Terry .

[CitroJim]

On a MK1 Terry, the fans should be running at half-speed at 90 degrees. Above 100 degrees they should be running on high speed.

Fan issues are very common on aircon Xantias and there have been lots of posts about the common issues. Look for posts by our Fan specialist Clogzz

One simple test to check the basic functionality of the fans is to disconnect the Bitron Sensor on the thermostat housing. This is the brown sensor. On disconnecting the plug to it with ignition on, the fans should run at top speed. If they don't suspect dirty/burned contacts on the trio of relays that live in a box between the fans.

MikeT's Blog contains a lot about his fan issues, now resolved.

Hope that helps Terry...

[dieseldoggy]

hi terry my post is still current.my ones that fan motors are playing up.we thought it was wiring after engine change.but one must have been lame then other one after running it like jim said then died but could be brought back to life by tapping/moving etc with brown plug off and ignition on.got to replace them this week.

[Chevron Terry]

Thanks for your help guys .
My Citroen is an , ZX 1995 diesel . I guess the brown sensor or possible Relay issue still applies .
Many thanks again
Terry .

[Sl4yer]

Fans should cut in soon after 90 is reached. 100 is far too much, and risks damage!

I've been through Dymock and it's a lovely part of the world BTW!

James

[CitroJim]

Terry, if your ZX is a non aircon model then it's possible the fans are controlled by a thermoswitch in the rad. Look for a hexagonal brass device on one side of the rad with three terminals on it. They do have a tendency to fail.

Some earlier vehicles had a resistor to effect the slow fan speed and this is known to go open-circuit, giving no slow speed but leaving high speed unaffected. At 100 degrees though, high speed should have cut in.

[Chevron Terry]

Hi ,
CitroJim,
Thanks for advice .
My ZX is a non A/c , and I replaced the Rad therm switch yesterday when I changed the Antifreeze .
So I guess its a case of checking the sensor s and relays by the thermostat .
Thanks again
Terry .

[Xantidote]

Hi Terry
In case you've not resolved fans problem:

My Xantia is 95 TD LX, non-aircon, with sensor in top of radiator on driver's side - maybe wiring similar to yours?

In the past, I checked fans' operation by removing the 3-wire plug from back of rad sensor, and shorting across the plugs' contacts, 2 at a time (can't recall which was earth wire). To get the fans to work at low & high speeds, I found the ignition key had to be at "ignition" position. If ign key set to "Accessories", then fans ran at low speed only. Hope of use to you

Martin