Re: How to drive a turbo

[rsco@lubrizol.com (Robert S. Cohen)]

Alan Callery asked-
>Al Powell said
>
>> [snip]
>>
>> Hey - if you can get a turbo, GET IT.  It's a stronger car and those
>> on THIS list know how to use synthetic lubes - and will instruct you
>> in how to drive a turbo so as to extend its service life - if you
>> don't already know.  Enjoy.
>>
>
>Could we create a "Top 10 List" on "How to drive a Turbo so as to extend its
>service life"?
>
>Thanks
>

OK- lets start with a top 3

1- Let it run for a little while before you drive it hard.
2- Let it run for a little while after you drive it hard.
3- Watch your oil carefully.


Turbos spin incredibly fast (the one in my Colt was spec'd to something
like 130k RPM or so). The speed at which they operate requires the bearings
to be well lubed. Letting the car run a while before hard driving (the kind
that would 'spin-up' your turbo) ensures that oil will have had time to
reach the bearings in the turbocharger. Letting the engine run a while
_after_ the turbo has been in use allows it to 'spin-down' from those
ridiculously high rpms with oil pressure maintained in the bearings. If you
just shut off the engine, the oil flow would stop while the turbo spins
on.....ouch. Also, the flowing oil removes some of the heat from the
turbocharger.

They also operate in the hottest portion of your engine, just downstream
from where combustion takes place. Turbochargers can get _very_ hot. This
heat can turn your oil into a goo that will clog up the passsages in the
turbo, kinda like a stick of butter in an artery. This is bad, and will
result in reduced oil flow. Turbos can be hard on oil. Running the engine
gently after a hard run will keep oil from stagnating in the turbo while
it's at its hottest.

I think I saw a post that said that Audi turbos were water cooled. Even if
this is the case, this does not affect the need to get oil into the turbo
before spinning it up, nor the need to maintain oil pressure while the
turbine spins down.

_____________________________________________________________________________
Robert S. Cohen

NewMedia Inc., 503 E 200th Street, Cleveland OH  44119-1545
voice 216.481.7900  fax 216.481.1570

The Lubrizol Corp., 29400 Lakeland Blvd  MS 228, Wickliffe OH  44092
voice 216.943.1200 x 2012 fax 216.943.7215

Email: rsco@lubrizol.com   rsc2@po.cwru.edu   cohen@nmedia.com
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