Re: Oil Change Frequencies

[Pearson-Franks Family <pearsonf@xxxxxxxxxxx>]

Hi, Steve.

Well, how much choice do you have?  It is my contention that
the frequent oil changes will far outweigh the startup 'dry'
risks.  Oil change is the only way I know of to remove the
tiny (technical term, I know ;~)  ) contaminants that make up
blowby and other 'bad' things.  And, the polymers in your
oil, whether dino originals or Man's Best Synth, break down
at some point in time.  Cheap enough to change it out,
recycling, of course!

It is my presumption that you are doing the oil change
hot, or at least warm, to get the oil viscousity down so it
drains in a reasonable length of time.  This will assure that
the oil passages have been recently filled with oil.  So the
startup wear picture is considerably brighter than the every
morning crankup from cold.

On my M30 motors, it is useful to prefill the oil filter cannister,
but I don't believe you have that luxury  :(.  You mention the oil
condition after X miles, which has a long and glorious thread on
the Digest, and I'm not gonna go there!  ;~)

Totally random:  where did 'MUDSCOW' come from?!?  I smell a story . . .

In longevity, Larry F.

>Date: Sat, 26 Dec 1998 14:28:56 EST
>From: MUDSCOW@domain.elided
>Subject: Re: Oil Change Frequencies
>
>It's time for my 3000 mile oil change again. However, someone who was recently
>sharing his formula for engine longevity pointed out the fact that each time
>the oil is changed, the engine is starved for oil on restart while the new oil
>is pumped into the system.
>I know this to be true since this is the only time the oil pressure light
>stays on for more than a second on start-up.
>
>How much wear occurs during this re-filling of the lubrication system with oil
>(con for frequent oil changes)
>vs
>How bad is the oil after 3k,4k,5k..10k
>(pro for frequent oil changes)
>At what point does the pro exceed the con? Benefit > Harm?
>
>Steve H
>89 325iS
>(standing by with oil, filter, and welding gloves at the ready...)
>Questioning the gospel...
>

Larry Franks
Issaquah, Washington
'86 535i x 2
'83 245 GLT (Swedish iron)

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