BoatBanter.com - View Single Post - Detroit 353 diesel -- aluminum block? How to tell?

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On Wed, 22 Aug 2007 21:05:57 +0700, wrote:

On Wed, 22 Aug 2007 12:27:55 GMT, "Pete C."
wrote:

Eisboch wrote:

"JohnM" wrote in message
m...

All two-stroke Detroits have a blower. It's necessary to the operation of
the engine, does the job that crankcase pressure does in a little
two-stroke. On the inline motors it mounts on the side of the block.

John

If a "blower" is defined by you as a turbo (i.e. .., device to increase air
flow into the cylinders), then you are in error. I know several people with
2 stroke DD 6-71's. Some are naturally aspirated, some have turbos
(blowers).

Eisboch

A "blower" generally refers to a direct driven super charger, not an
exhaust driven turbo charger.

The Detroit Diesel is a two stroke, diesel. The piston goes down on
the power stroke and comes up on the compression stroke. Without the
mechanical driven "blower" which simply blows air in through the
cylinder ports and through the exhaust ports at the beginning of the
compression stroke there would be no way to get a charge of air into
the engine.

If you wanted to increase the pressure and volume of this air flow you
could add a exhaust driven compressor before the "blower", But you
must have the "blower" for the engine to run.

Bruce in Bangkok
(brucepaigeATgmailDOTcom)

Neither being a two-stroke nor using diesel oil (nor indeed the
combination) requires a blower/turbo for such an engine to operate. It is
true that engines can be designed so that, were the blower/turbo with which
they are normally equipped to be removed they would not run, that would be
due to other design decisions, not to the choice of fuel, method of
ignition, and/or two/four-stroke operation.