Warming your engine . . .

[Chris <chris@xxxxxxxxx>]

Hello all!

So here it is, a little discussion on the how and why, to warm yer
engine.

"wendy wood" <dammwood@domain.elided> wrote: .>
.>You've got to be nuts.
Well not always . . .  :)

.>It takes a full minute for the oil to get to all parts of the engine
on the first start of the day, so driving immediately would have
negative implications at the same time.

I agree, but that wear and tear is nothing in respect to when leaving it
idling for ten minutes.
And ok I didn't mean drive off _immediately_  (what I do with my Alfetta
is: pull handgas (no, no choke) crank it, let it idle for about 20
seconds, till all cylinders fire and then drive off, this practice
helped me through 180.000+kms without problems) but of course, this is
an old engine . . . .

.>From what I know of cats is to remove HCs from the exhaust. I
believe that you would produce fewer at idle than at 3000 rpm even
driving
gently so the cat would get more abuse while driving cold.

Not true!
Well, ok, partially true.
When the cat is at it's _operating temp_. ie 98 celsius, it does the
work it's supposed to do, BUT when leaving your car idling for ten
minutes, the cat NEVER gets to it's operating temp and therefore doesn't
do anything for the environment.
AND a cat never gets abused, well with ledded fuel of course, but
there's no more around (sadly enough)

AND, if you drive of "immediately" the cat will get to it's operating
temp *sooner*, thereby lowering "dangerous" outputs than when leaving
your car idling...
BTW, did you know that a cat that isn't at operating temp produces H2S?
I'm sure you've smelled it before!
Just drive behind a car that just started up . . . now WHO FARTED!


.>Assuming your car is in fair condition I don't understand where all
the standing water and fuel is coming from over night.

Indeed, you don't understand.
When a 4-stroke engine fires, it burns fuel. (and a little bit of oil,
when it concerns alfa's)
This was not new to you was it?
But what you (apparently) don't know, is that an engine "leaks", i.e.
when fuel gets into it, it burns some of it, the burned gasses get out
of the exhaust (some of them). The rest goes into the, ... ehhh ...
welllll... we dutch call it "carter" I believe you call it "sump", and
there get mixed-up, dangled with, and dissolved in.... the oil you got
there!
Only when the oil reaches operating temps, it'll evaporate all the nasty
things in it.
And there's my statement, "drive off . . . your oil will like it."

.>This would seem even more important with wet
liner engines as the steel liners and the aluminum engine block and head
will all be expanding at different rates. I could understand how the
different rates would release some of the pinch on the head gasket. The
thermal stresses of going from -30C to full combustion temps in the
thousands is seconds and then driving makes my mind swim with
possibilities. My two cents.

All engines should be "warmed" properly.
The Alfa boxers for sure, and they're not even "wet-liners"!!
The thing with the aluminum blocks is this: when revving up when the
water's not hot, you'll crack the block, why? 'cause the liners "grow",
with their "growth" they lift up the head, which in it turn cracks the
block where it's studs are placed . . .

"And that's how you wreck an engine, lesson 1"

Your 2cents are donated to my: "Help me get my Milano back on the road"
fund, THANK YOU!

:))

Cheers!

Chris Piepers
The Netherlands

'81 Alfasud Sprint Veloce (for nostalgic reasons)
'83 Alfetta Q'Oro (daily driver, since the Milano is waiting for it's
new heart)
'86 75 2.5V6 (Milano)
(I just LOVE those transaxles)

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