Re: bmw-digest V9 #448

[TOMTLAM@xxxxxxx]

In a message dated 11/6/98 9:49:50 AM Pacific Standard Time, owner-bmw-
digest@domain.elided writes:

<< --------
 
 Date: Fri, 6 Nov 1998 09:21:31 -0800 (PST)
 From: bolhuijo@domain.elided
 Subject: Re: turbos, heat, & oil
snip 
 > temperatures be, BUT; remember that the oil not only lubricates the turbo
 > bearing, it cools the bearing. The bearing is integrally connected to the
 > exhaust turbine of the turbocharger, which gets *very* hot (someone who
 > knows numbers, feel free to chime in).
 
 <snip> 
 > winds up, and let it idle for about 30 seconds before shutting off the
 > engine after using the turbo (to let the turbine wind down before the oil
 > pressure goes away and to cool the bearing and housing), and you should be
 > fine.
 
  Some semi tractors have timers on the dashboard so you can dial in
 how long you want the engine to idle after you leave the truck, just
 so the turbo can cool down properly.  I doubt we'll be seeing that
 feature in any car soon though...
 
 <snip>
 
Date: Nov. 6th 1998
>From Tom Tlam  (tomtlam@domain.elided)
Sub.  Turbo cooling

I would agree with all of the above, I had a Saab 900 turbo years ago, great
car, expensive and oftened repaired.  This included replacing the turbo at 60
k because of heat destroying the oil seals.
My other "car" which I expect to have a long time is an F250 diesel which has
been turboed, wow what a diff., any way I added a post and prelube oil pump
with runs for about 1-2 min. before starting and after shutting down. This may
be over kill but so is the truck. 
All large engines and most medium speed engines use pre and post lube pumps
and run for 10 to 40 K hours between overhauls.  Figure that in miles, PS. all
marine engines are high performance engines due to the fact that they are
usally at or near fully lload. This is most unlike automotive engines even
trucks.

regards Tom

BMW CCA 158854
87 528e @ 201K

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