"Steve Lusardi" fired this volley in news:if44ms
Funny, that... When they trained us in Vallejo and when we worked on
them 'Nam, they always _told_ us we were working on 651s AND 653s.
There were a lot of older boats with them. (older being sort of relative,
since the "glass slippers" didn't last very long, but we salvaged and re-
used anything we could, down in the tippy-tip muddy end of IVCorps.
When I came back in-country and did some work on a few touring busses, I
found there were lots of 651s around.
I even have a personal anecdote where an adjustable wrench got left on
top of the blower on a 651-powered bus. After a 200-mile round-trip to
Washington, D.C. and back to the barn, the wrench never fell off...
The 1271s were that smooth, too, if they were in half-way decent shape.
Gunner Asch fired this volley in
The 12V71s had a reputation for the rack jamming (actually, the governor
link) and running away. Our machinist mate told me (but I never saw it
happen) that he had something like 15 seconds to lift the hatch, jump
down in between the engines, pop the rack cover, and manually jack the
rack to OFF.
I think I'm glad I never did see it, as that engine had a max working RPM
of 2450 on the boats, and supposedly red-lined at about 3600.
My DD353, there is a intake shutoff, just pull on it lightly and all
intake is stopped.
I lifted the engine yesterday (on blocks). The pan has a small leak, I
put a plastic tub under it.
I ordered a gasket, when I reinstall the oil pan, I will be sure to
have a shutoff hooked up for easy shut down.
that motor on some APCs and those are very rare.
in-line 53s is very true. Many of the parts are
53T motors is that they use a blow through blower, as
that use twisted rotors. When the turbo boost
pressure to shift an internal bar in the rotor against an
drilled holes in the rotors. DD stated that relieving
DDAs were very high tech motors and way ahead of
Back when I was growing up in Elmira Ontario there was a guy ran a
small excavating business - basically a back-hoe service - and had a
late 50's GMC dumptruck with a 6-71 and a hi-hoe with a 3-71. The 6-71
"talked" through 2 staight pipes about 5" diameter up the back of the
cab, and when Ibra opened that thing up going up the hill out of town
towing the 'hoe it was music to a motorheads ears!!!
Having the 3-71 and 6-71 meant he only needed to keep one set of
spares to service both units.
Same oil filter, same fuel filter, most of the gaskets, etc.
He dug wells with that 'hoe and would often have it so far down in
the hole you couldn't see the boom, and he'd crab it back out on it's
own, using the bucket and hoe.
Agreed re: runaways. I was told a story about a LARGE marine
engine where the teller's farther was the hero; everyone else
fled and he rammed a bale of cotton waste into the air intake,
stopping the engine. It too had an air cutoff door, but the
runaway just ate it & kept going.
I ran into this with a VW Rabbit a friend owned. Not good.
Burning SAE 10W-40 vs #2 melts the glowplugs as well as not
stopping when you need it to.
I like the CO2 idea; just be sure it's not a dry power
extinguisher when you grab it.
If dry powder is all you got, it will probably work in a pinch and would be
better than letting the engine blow apart. I wouldn't want to predict what
damage the powder would do to the engine though.
In preparing to extinguish a small engine room fire caused by a welder I once
had a Chief MM snatch a dry powder extinguisher out of my hands before I could
trigger it. He quickly replaced it with a CO2 unit which made a lot less mess
than the dry powder would have.
That powder is VERY corrosive inside a running engine... Most insurance
appraisers will declare the engine SCRAP, if it was stopped with a Dry
Chemical Extinguisher, or require it to be IN-Framed before they would
insure it on a Machinery Policy, again.... Just say'en....
It better be a BIG CO2 extinguisher though. A 671 wound up is 750cfm
at 3000 RPM at atmospheric - at least double that through the blower,
so you need a good 1500 cu ft of CO2 to be sure you are going to bring
it to a halt - and a runaway g71 will be a lot more than 3000 RPM -
more like 6000, so at least 3000 CU ft of CO2 available to the intake.
Thats something like 400 POUNDS of CO2 (based on 556 cu meters per
tonne at 70F and 1 atmosphere)(15012 cu ft/tonne)(6.23 cu ft/lb)
Based on information from
OK, so you don't need 100% CO2 charge to stop the engine - but suffice
it to say a 25 pounder isn't going to cut the mustard . The engine
will progressively slow down, inhaling less CO2 as it slows down, so
I'd say a 50 lb or 2 25lb extinquishers would be MINIMUM to have
available if you are counting on killing a runaway 6-71 (426 cubic
inch displacement 2 stroke)
Besides the mess, a standard dry chemical extinguisher is not going to
be nearly as effective as a CO2, and will definitely require an engine
teardown (adviseable after a run-away in any event - but a lot messier
when filled with powder.)
I've seen a pair of coveralls go through a runaway deisel before the
chunk of steel plate slapped over the intake finally did the job.
It was a six cyl turbo deisel - not sure of the make or model as it
was something like 30 years ago.
Powder makes a terrible mess, but less so than toasted corpses do.....
it really is magic for burning liquids such as fuel oil/gasoline/etc.
CO2 extinguishers are downplayed by firefighter types...they
don't work well at all outdoors, etc.