well ill be damned...

http://www.abc.net.au/science/articles/ ... 044311.htm

yep, and I think the key thing is that you want the engine to go from cold to normal as quick as possible. Note that even in the BMC Handbook they have in bold "reach correct working temperature as quickly as possible"

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68 Morris Cooper S Mk1 (*ex 78 1275 LS 4th last built, 70 Morris 1500 OHC & 70 MiniMatic)

Yeap, I'd agree. It's not so much the coolant temp that you want to warm up, but the Oil. Cold Oil doesn't lubricate as well as Oil at running Temp.

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The SU carby has a 2-stage choke. The first stage (when it's out only a little) is a fast idle - it's just like holding the accelerator down a little.

The second stage (when you pull the choke all the way out) enriches the mixture for cold starts. You only need it this rich to start it, so start it with the choke all the way out, then push it back in to the fast idle.

So, if you have no choke, it's just like you're only using the fast idle. Pumping the pedal will not enrich the mixture, just allow more mixture in (and it won't need any more at 1000rpm).

I've always let the car idle for up to about 30 seconds - this is when I'm choosing a CD or a station to listen to :)

IRT warming up before I drive off - I only let it idle at 1000rpm for the time it takes to reverse out of the garage, close door, scull coffee, get something on my uniform(dirt, grease etc!!), curse for getting my uniform dirty before I even get to work, lock the front door and then I drive off (2-3 mins max). Once I have driven a kay or so, I push the choke all the way back in again as it idles properly once warm. The second stage of the choke activates/engages the cam on your SU which lowers the needle tube and lets more fuel into the bridge area of your SU. I drove from Marulan to Canberra with the choke out once and wondered why I was using so much fuel...

Have done this ever since I have owned the mini and the engine had a smidge over 300,000km on it(finally let go a bearing - intentionally trying to spin them!!)so warming it up, within reason of course, has little effect on wear really. Modern cars are designed to turn key and go from cold and my EB XR8 is turn key and drive(have an auto door now!!) .

Ahhh gotta love Canberra weather!!

Hooroo

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Rob Forsyth
Miniot!!

This is actually very interesting. nice thread!

Question to add to it. I have a garage at the bottom of a hill which is flat at the garage, steepish until about 10m away from the garage and then quite steep from 10m to the top of my driveway where the house meets the road or about 20m.

I usually start the Moke, let her idle for about 2 mins, and then its back and forward a bit to get out of the garage, then I reverse up the driveway. I do this in the Rover (auto) as well.

Am i putting huge strain on the engine/box reversing up the driveway? Should I drive up forwards? I know its a little off topic, but I am interested in the idle to warm up vs drive to warm up vs dont strain your car during warm up debate.

It'll be fine as lone as you don't try to do in in less than 0.03 seconds (I think you get what I'm driving at )

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Yeah, I think if I had a steep drive like that or you lived somewhere really cold then it would make sense to give it a minute or so idle, but as the handbook states better for it to be a nice fast idle than normal speed idle. As for forward vs. Reverse which is lower ratio or are they the same. Can't imagine a big difference anyway.

When I was growing up our neighbor would every morning start up his V8 panel van then go inside and eat his breakfast while it idled away for 5-10 minutes. Then he would come back outside and hose the dew off the car as
he drank his coffee before driving off.

That's the kind of warmup which is bad news but there is a lot of people who think that is a good thing.

As both Dr. Karls article linked above and the Mini Handbook, even though they are written 45 years apart, state the key aim is to get the engine up to normal temp as quick as possible and usually the best way to do that is to get the car out on the road.

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68 Morris Cooper S Mk1 (*ex 78 1275 LS 4th last built, 70 Morris 1500 OHC & 70 MiniMatic)