Any reason semis do not use diesel-electric engines?

anumber1 wrote:

>
> Most north American locomotives do not use anti-freeze compounds in the
> engine's coolant so it is important to drain a locomotive of coolant if
> it is to be left shut down in sub-freezing temperatures.
>
> Al G


Isn't that a by-product of the fact that the old EMD 2-stroke diesels
are so prone to weep coolant into the crankcase around the
cylinder-to-case junction, and while water will just evaporate
antifreeze mixed with oil turns abrasive? And isn't it also true that
the newest engines (EMD 4-stroke "H" engine and both the GE GEVO v12 and
7HDL v16) do recommend the use antifreeze?

Steve wrote:
> anumber1 wrote:
>
>>
>> Most north American locomotives do not use anti-freeze compounds in
>> the engine's coolant so it is important to drain a locomotive of
>> coolant if it is to be left shut down in sub-freezing temperatures.
>>
>> Al G
>
>
>
> Isn't that a by-product of the fact that the old EMD 2-stroke diesels
> are so prone to weep coolant into the crankcase around the
> cylinder-to-case junction, and while water will just evaporate
> antifreeze mixed with oil turns abrasive? And isn't it also true that
> the newest engines (EMD 4-stroke "H" engine and both the GE GEVO v12 and
> 7HDL v16) do recommend the use antifreeze?
>
Yes, in EMD's case, the 567 and 645 were prone to leak in the manner
described and yes, the water (with a an anti-corrosive package added to
"sweeten" the coolant) would just evaporate from the lube oil, making
the seepage acceptable in the long run. I believe the problem was cured
with the design of the 710.

None of the newest locomotives are using anti-freeze at this point but
employ instead self start systems that cycle the engine on and off to
maintain engine temperature above freezing. I would imagine that they
are in fact designed to accommodate anti-freeze now but the railroads
are quite slow to adopt non-electronic new technology.


The two foot wide exhaust stack is still the primary ingress of water
into the engine however. Many of the shortlines get around this by
capping the stack, using electric engine block heaters powered by
commercial, land based power and rigging self draining mechanisms should
all else fail.

anumber1 wrote:

>
> The two foot wide exhaust stack is still the primary ingress of water
> into the engine however. Many of the shortlines get around this by
> capping the stack, using electric engine block heaters powered by
> commercial, land based power and rigging self draining mechanisms should
> all else fail.

The local shortline has (had? haven't seen it in a while) an older
non-turbo GP with the "liberated exhaust" mod (4 stacks instead of 2
rectangular stacks). But since it sits idle a lot, each stack had a
chimney flue style weather cap. Darn thing looked like it had 4
wood-stoves inside the hood!

Very interesting post, thanks

Yep. For all these reasons, I'd expect to see hybrid and possibly
diesel-electric drives on local delivery vehicles first.

One additional advantage of all electric drive that can be achieved by
placing motors in the wheels is a flexible chassis design. By
eliminating the driveline, differential and solid axle, one could build
something like a step van with a lower floor. Of course, for small vans,
front wheel drive gets you the same thing.

--
Paul Hovnanian
------------------------------------------------------------------
Entropy: When your shoelace comes untied, you can't fix it
by walking backwards.

"Paul Hovnanian P.E." > wrote in
:

> Yep. For all these reasons, I'd expect to see hybrid and possibly
> diesel-electric drives on local delivery vehicles first.
>
> One additional advantage of all electric drive that can be achieved by
> placing motors in the wheels is a flexible chassis design. By
> eliminating the driveline, differential and solid axle, one could build
> something like a step van with a lower floor. Of course, for small vans,
> front wheel drive gets you the same thing.
>

But with motors in the wheels,it increases the unsprung weight;not a good
thing WRT handling and suspension(heavier components cost more).

and the motor bearings get a beating.

--
Jim Yanik
jyanik
at
kua.net