[AT] Oliver 990

[Steve W.]

charliehill wrote:
> You probably have Ralph and didn't know it.  They were common in tractor 
> trailer trucks in the 60's and 70's.  Often called 318 Detroits or 350 
> Detroits which was their HP rating.  There was a version of the 8V92 called 
> a 8V92TT.  It was supercharged and had twin turbochargers (TT).  It was 
> about 425 hp set up for a truck.  The RPM operating range for those engines 
> was 1600 to 2450 RPM.  Being 2 stokes they were not intended to be lugged or 
> run at low rpm and usually had at least a 10 speed transmission and most of 
> the time a 13 or 15 speed.  Once you got used to all that shifting they were 
> a lot of fun to drive.   The 13 speeds were basically a 5 speed with a 
> direct drive and a low and overdrive aux. gear on the back end of the tranny 
> that was shifted with an air valve so you didn't have to shift the lever as 
> much as it sounds like.

Add in just about every large custom fire engine built and many boats
and road equipment.
There are two easy signs that a vehicle has a 2smoke Detroit in it.

Look under it and you will usually see large oil spots (have yet to see
one that didn't leak oil)
Look near it for the 33 or 55 gallon drum of oil for it (have yet to see
one that didn't need some oil added if they were being used)

The Detroit is a fun engine but it does have one MAJOR drawback. Because
of the engine design it is possible for them to run backwards! We had
the ALF engine in service for about 2 weeks when one of out crew parked
it on a slight incline. He was trying to back it into a driveway and
lugged it down enough that it flipped.

This drawback in trucks and dirt equipment was a bonus when used in a
boat. They actually would set up one engine to run clockwise and one
counter-clockwise to negate the torque effect. Plus they could shut
down, hit a different selector and the engines would run in reverse to
allow better dock and station keeping.

The other minor problem involved the way they feed oil and fuel into the
engine. The design is OK unless a couple seals fail. Or the fuel rack
control fails. Then you get a runaway engine. In this case you hit the
control found ONLY on a Detroit equipped engine. The Emergency Shutdown
switch or lever. It closes a BIG flap in the intake and shuts off the
airflow into the engine.

-- 
Steve W.