FAN TEMP SENSOR POSITION

[NonMember]

9 hours ago, johny said:

I think if the electric fan is set up to run on after engine stop the thermosyphon effect will be considerably increased at least until the wax thermostat closes

Correct. You will still get heat soak but it won't be as pronounced.

[johny]

Yes I'm quite pleased by the way the temperature rise after stopping the engine is controlled now. It certainly helps a lot with a hot restart as the fan running reduces under bonnet heat build up as well....

[Guest]

I have the electric fan on my Vitesse set-up to run on after the ignition is switched off - should circumstances dictate.

On occasions I will open the bonnet after a hot run and that usually cuts the fan running time by a half, which certainly indicates the level of heat being trapped within that confine. 

[NonMember]

When I bought my Vitesse, it had a Kenlowe fan controller with the probe in the top hose. No ignition control so would run after engine stop. On evening, after I'd parked up at a mate's house for a band practice, I went back out to fetch something from the car, and the fan was still running an hour or so on. The coolant level had got a bit low and the fan was having no effect on the (now dry) sensor. I needed a jump start.

[Guest]

That's interesting Rob, I have never been able to fathom why Kenlowe employed that capillary sensor / bub set-up in to the top hose; with their know-how I always thought the company could have done something better. On the flip side they sold thousands of these fans - obviously worked and car owners were happy with the product.

I like the dial sensor they used, but the bulb - no !!

Regards.

Richard.

[Clive]

I think the bulb idea was a "simple solution" and required nothing except the proper little insert that nobody can ever find, and I found some sealant helped too. 

I recall another company using a sensor shoved into the radiator fins? Again, a simple answer.

Indeed, inline hose adaptors with a sensor hole are the best answer. Though I have always been intrigued by the MGB (and other cars) solution of a simple hole in the header tank, a grommet and a sensor push-fits. My Dad had an MGB with that setup, and it definitely worked, didn''t leak and the sensor was indeed easy enough to pull out and refit. I have never been brake enough to try it on another car though.

[johny]

+1 for the push in rad fins sensor

[NonMember]

I used a push-in-the-fins sensor on the OTT variable speed controller I replaced the Kenlowe one with. Worked great until the other week, when it didn't seem to be seeing any heat, but that might be the condition of my radiator fins...

[johny]

Hmmm sounds like new rad should be on the shopping list and if the budget is tight I really recommend an ally chinese Honda Civic one even though it does require a bit of fettling. Also is your controller powered up all the time to allow the fan to run on?

[NonMember]

There's a new rad in the loft waiting to be fitted.

The controller has a permanent power feed to allow fan run-on but it switches itself off once cold or after a timeout (quiescent draw is less than a microamp).