Is it normal for the radiator fan turn on and run for a while after the engine is switched off? This happens with my car even if the rad fan wasn't on while engine was running. It turns itself off after a few minutes.
I agree that is normal however there is a reason for it,what is the gauge showing ? is this happening after short or long run,like a trip up to the shops or after a motorway journey for example,if a short run you may have a blocked radiator or faulty thermostat,I had this with a badly blocked radiator which after a short time blew out after my engine swap,was amazed how much crap was in it. I did a full flush of the cooling system twice and the same crap was in the engine block !!.
On the carb cars, radiator fan after-run is triggered by the carb body getting hot through heatsoak, and tripping a thermoswitch mounted there. May be worth seeing if that wire is shorting to ground (which is what the thermoswitch does with it at temps above threshold, if memory serves).
Thanks both. Car has been sat for a couple of years and a weber carb conversion of unknown pedigree. Will check and report back
There's a photo in this thread showing the thermoswitch and its associated wiring connector on an original 2e2 carb. Pierburg 2E2 Carb sensor? | Club GTI I doubt there's any such thermoswitch on your Weber, so try to find where that black wire/connector is, and make sure it isn't grounding/earthing.
the wire is actually brown or brown/black with a black outer sheath, so look carefully at where the wire enters the spade crimp. solid black wires are generally ignition lives so dont want to mix them up (for anyone who might stumble on this and attempt to put an ignition live to the thermoswitch, this would be very bad )
Excellent point; I must admit I was surprised how thick the 'black looking' wire appeared to be in that pic.
not really an issue in this case but thought it was worth mentioning all the same. if you did put ignition live to the switch you would have a wire which only melts itself when the engine warms up
I think any ignition 12V (actually) black wires that used to go to the Pierburg are fused aren't they? Or was there a thing where on CE1 cars they weren't, CE2 were, or vice-versa? Can't remember where I used to get wiring info back in those days. The thermoswitch wire went to/came from a relay in the cabin, I think?
not all of them unfortunately, ce1 theyre all fused now you mention it though but ce2 the carb and cut off heaters are fed direct from the same feed as coil
