mikerowe Wrote:
=======================================================
> Your faithful servant has beeen working the past
> few weeks on D&S #7's sister engine, #4, at the
> Colorado Railroad Museum (see photo, below). Dead
> batteries were the initial complaint (lack of use
> more than anythign else). I have been changing
> fuel filters (and oil and oil filters soon) and
> diagnosing and fixing a hard start problem on
> engine #1. Phil Johnson from the Loop has dropped
> in and worked on balancing the air throttles so
> the gensets load more or less equally. Someone
> else (name?) is installing a "train air" brake
> system in the locomotvie; #4 came to us equppied
> only with "straight air" brakes for the locomotive
> only. #4 will become the mainstay for the new
> monthly "Riding the Rails" operating days third
> Saturdays, but only when steam isn't scheduled.
>
> #4 and #7 are rather interesting n.g. locomotives,
> designed for use by the steel mill industry to
> haul "bottle" cars about the mill grounds,
> transporting molten steel to various parts of the
> plants to be made into different products;
> alternately, they would haul slag cars from the
> furnaces out to the dumps.
>
> These locomotives were more or less standard
> 44-tonners ballasted up to 50 tons with steel deck
> plates that are close to 3" thick. Each truck
> extends out from under the front/rear of the
> locomotive to house a larger-than-normal traction
> motor geared to the outer axle; the inner axles
> are chain driven from the outer axles. Yours
> truly is a little surprised at how fast the D&S's
> #7 was moving down the track, because these
> locomotives are sloggers, not racers.
>
> Drop by the CRRM on any third Saturday which does
> not have a steam special event scheduled, and you
> will likely find #4 on the point of the train.
>
> PS. Guys around the museum have taken to calling
> #4 "the bus." Why? Because #4 is equipped with
> two Detroit Diesel in-line 6-71 engines. Those of
> us of a certain age will remember when the 6-71
> was almost ubiquitous in city transit and
> interstate buses, and a lot of commercial trucks
> too. And indeed, when the #4 revs up, by golly,
> it sounds just like a bus! The 6-71 is a
> two-cycle engine, with exhaust beats coming with
> every cycle of the piston, not every other cycle.
> So they always sound like they are churning at a
> furious rate, when in fact they do not turn any
> faster than any other type of mediun-duty truck
> diesel engine.
>
> Mike
>
>
I remember 6-71's well. The 6-71's I was around had blowers or super-chargers to clear exhaust and push new air into cylinders vented with holes at bottom of stroke. I think GM also made them maybe earlier than Detroit Diesel. Drive shafts for the Super-charger blower was a big failure issue at least on the earlier versions.
Are the engines on the #4 Super-charged with blowers also or they aspirated?
