i think what kens saying means its muff time! put it this way... it's around 5 in northampton and it took lily a good 2 miles before any warmth was coming in... im putting mine one! only short journeys tho

Graham,
no need for any confusion.

Don't forget that an A series engine will work fine with ambient temperatures exceeding 30 Centigrade.

However, since there is no thermostatic control of the cooling such as can be found on other air-cooled engines, an A series engine does require the flow of cooling air to be restricted in temperatures below 'about' 10 Centigrade, otherwise its oil won't reach a proper working temperature.

Afaik, our Finnish friends will even block off the air flow through the oil cooler in sub-zero conditions...

I particularly liked the next to last paragraph in this article from a VW site.
< http://www.vw-resource.com/remove_thermostat.html >

Of course, for A series Citroens, the grille muff is as close as we can get to a thermostat.

ken

( p.s. Joe, you're missing the point completely by assuming that the length of the journey is of any significance. )

When I'm on my way to work, I drive 90% on the motorway and don't use the muff. Because of the higher revs/speed for a long time the oil gets at the right working temp.

To bad thos Acad's have a plastic muff. If they where made from the same material as de early ones on 2cv you can fold them up so they let more air through.

I thought this would set a rabbit running.

So here is my four peneth.

The main problem is the variations in temperature in the UK. Whilst you can wake up to a frost in the morning [-3 ] by lunch time you can be at +12.

If the air flow on a 2CV was thermostatically controlled, the flow would be restricted when cold and wide open at the higher temperature. In effect people should set off with muff on and take it off later in the day. How many people do that.

My issue with a muff is that people fit and forget. It would therefore be much better not to fit a muff in the UK unless a sustained cold snap is forecast where day time temperatures remain less than +5 degrees.

I have no other issues with muffs, in fact they can be good fun in the right environment

I've not fit my muff and don't normally unless it is really freezing and theres thick ice on the windows

i find once the engine has got to running temp i get more engine power with the colder air anyway

should this be in a new thread btw

A new thread all about muffs, wow

Yes please

ah a muff on your face now that is unusual

Paul,
here's Citroen's 10 centime's worth, from the owner's manual.
"Below 10 C, fit the grille muff.
Above 15C, remove the grille muff."


Fwiw and disregarding the other downsides of engines running below their correct operating temperature, I've known 2CV racers _reduce_ their lap times considerably during an event held in wintry conditions by restricting the flow of cold air through the grille...

ken.