Ignoramus5626 wrote:
On 2015-09-16, Lloyd E. Sponenburgh lloydspinsidemindspring.com wrote:
John B. fired this volley in
:

I believe that the manual dampers were actually a Detroit Diesel
furnished device as they were common on engines that ran mostly
unattended like air compressors.
Yeah... I wasn't commenting on who made them, but just when, in the line of
models, they came.

They definitely were NOT on the Mk-I boats. I spent a good deal of time in
the bilges on that model.

The dampers are a relatrively recent invention, like 1970s

The dampers are common on civilian stuff.
Probably typical military BS in believing the contractor knows what they
are talking about when they said "Oh those things aren't needed"........
OR they were afraid that they could get tripped and kill the engine (and
the crew if it occurred at the wrong time)

There is one time they don't work. If the engine somehow gets started in
reverse direction of normal rotation! One of our crew did that at a
fire call. He had pulled the rig into a driveway, left it in reverse and
jumped out. He forget to pop the brakes!!! Thing was nice and warmed up
from the trip and it turned over about twice and fired up! Was dumping
exhaust out the intake boxes and gulping air up the exhaust. The driver
was freaking out. I walked over, told him to jump in, pop the brakes and
stand on the brake pedal. Then just shoved a traffic cone in the
exhaust. It died pretty quick between the gearbox and choking it.

I said normal rotation because the Detroits were built in clockwise and
counter-clockwise rotation depending on application. Plus some were both
and you shifted the racks to reverse the engine.

--
Steve W.

Garrett Fulton wrote:
On Tuesday, September 15, 2015 at 10:07:29 AM UTC-4, Lloyd E.
Sponenburgh wrote:
Garrett Fulton fired this volley in
:

? Did you not mean to check out the bearings on the blower? I
believe that would likely be the bigger problem on an old
Detroit.
No; given the relative speeds of operation, and their temperature
domain, those in the turbo are the more likely ones to fail early.
To my knowledge, we never had a Roots failure in our two divisions
of Swift boats, unless one got shot up.

They were rebuilt every time a boat went in for overhaul, but every
moving part in the engines was replaced or re-machined then.

Also, on that thing about the runaway condition -- I think it was
on the Mark II boats (real pigs in performance) that they started
putting a manual damper over the blower inlet, so if the engine
mate was fast enough, he could shut one down very quickly. Prior
to that, the only solution was a very dangerous one... he had to
jump down into the compartment (between the two engines) spin off
the injector cover nuts, and slam the rack by hand! It could have
been the Mark III boats where they began to add that (luxury yachts
compared to the Mark I boats!)

Lloyd

I stand corrected. Was a diesel truck mechanic many years ago, but
never had any close experience with the Detroits. Turbos seemed to
last forever on the Cummins engines, hence my question.

Garrett



Only time I saw a scavenger pump have issues with the bearings it ate
the rotors and locked it up. Turbos on a screamin' Detroit get a LOT
more heat than a 4 stroke.

The 2 stroke design is also why they sound like they are screaming even
at low rpm. Twice as many power strokes per rev than a 4 so it sounds
twice as fast.

--
Steve W.

On Wednesday, September 16, 2015 at 3:29:19 AM UTC-4, John B. wrote:
On Tue, 15 Sep 2015 20:20:16 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

John B. fired this volley in
:

I believe that the manual dampers were actually a Detroit Diesel
furnished device as they were common on engines that ran mostly
unattended like air compressors.

Yeah... I wasn't commenting on who made them, but just when, in the line of
models, they came.

They definitely were NOT on the Mk-I boats. I spent a good deal of time in
the bilges on that model.

Lloyd

I don't know about river boats, but we had Detroit Diesel powered
supply boats and one WW II landing craft on several jobs I worked on.
As I remember, none of them had the damper shutdown valve. But nobody
was shooting at us :-)

--
cheers,

John B.

I was an engineman on the USS Mars (AFS-1), AKA 'Ichi Bon Benjo Maru', from '68 to '71. We had slanted 6-71's under the rear decks of the OMB & gig.. Output was forward thru a F-N-R Allison transmission to a vee-drive. These engines were probably made around 1960 or so.

They just had an intake 'silencer'... a flat metal box directly on top of the blower with intake grills at both ends... maybe 8" x 2" (?) each. We were told that if we had a runaway, grab two foul weather jackets, life jackets, or whatever else came to hand and stuff them over the ends of the intake boxes. I never had that experience, and I'm just as glad.

Our big 7-cylinder opposed-piston Fairbanks-Morse (2071 cid, IIRC) emergency diesel generator had a spring-loaded shutoff flap in the intake tract before the blower. It was operated by an automatic overspeed trip on the engine's governor, backed up by a big polished aluminum panic button that also operated the linkage to release it manually. We tested the overspeed shut-off (in theory) every 6 months during PMS by cranking up the speed dial on the governor. In reality limited manpower let us actually test it about every 12-15 months. But it was friggin' awesome to choke that huge mass of moving metal down from just over 3600 rpm to zero in seconds... shook several adjacent compartments.

Jim H. "The Navy: It's not just an adventure, it's a ****in' dirty job!"

Gunner Asch on Mon, 14 Sep 2015 17:37:12 -0700
typed in rec.crafts.metalworking the following:
On Mon, 14 Sep 2015 17:34:00 -0500, Ignoramus29663 wrote:
On 2015-09-14, Gunner Asch wrote:
On Mon, 14 Sep 2015 06:40:12 -0500, Ignoramus29663 wrote:
On 2015-09-14, Ignoramus29663 wrote:
On 2015-09-14, Gunner Asch wrote:
On Sun, 13 Sep 2015 21:39:38 -0500, Ignoramus32337 wrote:
[...]
That optical comparitor went for some serious money. Similar ones
sell here in California for about 1/3rd of that
Gunner
What comparator?
Lot # 98
http://www.bidspotter.com/en-us/auct...a-a4f7014d0d9e

I do not see the price on it, how did you find out how much it sold for?
Oh, the auction has prices, sorry, they usually do not provide that inf
$4,124, with 134 bids, as I recall.
Even on Ebay..thats high as hell.
Gunner
I consider all comparators to be garbage , buy them only for garbage
prices.
Why do yo consider a very useful device to be garbage?

Doesn't know how to use one?

Last one I bought for $50 and sold for $700.
Doesnt sound like they are garbage if you can make that kind of
markup.

Kind of reminds me of one of the Freewheein' Franklin Freek
stories. Seems he was down in Mexico, and realizing he was unlikely
to be able to hitch a ride north with long hair, he divests himself of
his stash, and tuck his hair up into his hat. Up pulls a pickup with
camper, and stock blue collar type character (buzz cut, white tee
shirt) driving. After assuring the driver that he did not have any of
that pernicious maryjuwanna on him, Franklin gets a ride. After they
cross the border, 'Buzzcut' apologizes for possibly being unfriendly,
but the camper is just stuffed full of pot, and he didn't want to be
stopped. Franklin thinks to himself "How can this be? He doesn't
seem 'hip' maybe I can score a little," and asks "So, what do you plan
to do with all of that stuff?"
Well, Mr Buzzcut then explains the going rates in various cities
around the country, which causes Franklin some dismay - the man is hip
to the market. Then Mr Buzzcut says "You seem to be the sort who
might be able to answer a question I have about this stuff. Namely -
what is it that you all _do_ with it?"

tschus
pyotr
--
pyotr filipivich
"With Age comes Wisdom. Although more often, Age travels alone."

On Wed, 16 Sep 2015 07:56:22 -0400, "Steve W."
wrote:

Garrett Fulton wrote:
On Tuesday, September 15, 2015 at 10:07:29 AM UTC-4, Lloyd E.
Sponenburgh wrote:
Garrett Fulton fired this volley in
:

? Did you not mean to check out the bearings on the blower? I
believe that would likely be the bigger problem on an old
Detroit.
No; given the relative speeds of operation, and their temperature
domain, those in the turbo are the more likely ones to fail early.
To my knowledge, we never had a Roots failure in our two divisions
of Swift boats, unless one got shot up.

They were rebuilt every time a boat went in for overhaul, but every
moving part in the engines was replaced or re-machined then.

Also, on that thing about the runaway condition -- I think it was
on the Mark II boats (real pigs in performance) that they started
putting a manual damper over the blower inlet, so if the engine
mate was fast enough, he could shut one down very quickly. Prior
to that, the only solution was a very dangerous one... he had to
jump down into the compartment (between the two engines) spin off
the injector cover nuts, and slam the rack by hand! It could have
been the Mark III boats where they began to add that (luxury yachts
compared to the Mark I boats!)

Lloyd

I stand corrected. Was a diesel truck mechanic many years ago, but
never had any close experience with the Detroits. Turbos seemed to
last forever on the Cummins engines, hence my question.

Garrett



Only time I saw a scavenger pump have issues with the bearings it ate
the rotors and locked it up. Turbos on a screamin' Detroit get a LOT
more heat than a 4 stroke.

The 2 stroke design is also why they sound like they are screaming even
at low rpm. Twice as many power strokes per rev than a 4 so it sounds
twice as fast.
And produces roughly twice the power ith the same displacement at the
same speed.

On 2015-09-16, Steve W. wrote:
Ignoramus5626 wrote:
On 2015-09-16, Lloyd E. Sponenburgh lloydspinsidemindspring.com wrote:
John B. fired this volley in
:

I believe that the manual dampers were actually a Detroit Diesel
furnished device as they were common on engines that ran mostly
unattended like air compressors.
Yeah... I wasn't commenting on who made them, but just when, in the line of
models, they came.

They definitely were NOT on the Mk-I boats. I spent a good deal of time in
the bilges on that model.

The dampers are a relatrively recent invention, like 1970s

The dampers are common on civilian stuff.
Probably typical military BS in believing the contractor knows what they
are talking about when they said "Oh those things aren't needed"........
OR they were afraid that they could get tripped and kill the engine (and
the crew if it occurred at the wrong time)

There is one time they don't work. If the engine somehow gets started in
reverse direction of normal rotation! One of our crew did that at a
fire call. He had pulled the rig into a driveway, left it in reverse and
jumped out. He forget to pop the brakes!!! Thing was nice and warmed up
from the trip and it turned over about twice and fired up! Was dumping
exhaust out the intake boxes and gulping air up the exhaust. The driver
was freaking out. I walked over, told him to jump in, pop the brakes and
stand on the brake pedal. Then just shoved a traffic cone in the
exhaust. It died pretty quick between the gearbox and choking it.

I said normal rotation because the Detroits were built in clockwise and
counter-clockwise rotation depending on application. Plus some were both
and you shifted the racks to reverse the engine.


This was a really funny story, though I am sure that it did not look
funny in-person.

i

Here's a picture of this generator.

http://igor.chudov.com/tmp/Detroit-Diesel-6-71.jpg

i

On Wed, 16 Sep 2015 07:55:49 -0700 (PDT), "Jim H."
wrote:

On Wednesday, September 16, 2015 at 3:29:19 AM UTC-4, John B. wrote:
On Tue, 15 Sep 2015 20:20:16 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

John B. fired this volley in
:

I believe that the manual dampers were actually a Detroit Diesel
furnished device as they were common on engines that ran mostly
unattended like air compressors.

Yeah... I wasn't commenting on who made them, but just when, in the line of
models, they came.

They definitely were NOT on the Mk-I boats. I spent a good deal of time in
the bilges on that model.

Lloyd

I don't know about river boats, but we had Detroit Diesel powered
supply boats and one WW II landing craft on several jobs I worked on.
As I remember, none of them had the damper shutdown valve. But nobody
was shooting at us :-)

--
cheers,

John B.

I was an engineman on the USS Mars (AFS-1), AKA 'Ichi Bon Benjo Maru', from '68 to '71. We had slanted 6-71's under the rear decks of the OMB & gig. Output was forward thru a F-N-R Allison transmission to a vee-drive. These engines were probably made around 1960 or so.

They just had an intake 'silencer'... a flat metal box directly on top of the blower with intake grills at both ends... maybe 8" x 2" (?) each. We were told that if we had a runaway, grab two foul weather jackets, life jackets, or whatever else came to hand and stuff them over the ends of the intake boxes. I never had that experience, and I'm just as glad.

Our big 7-cylinder opposed-piston Fairbanks-Morse (2071 cid, IIRC) emergency diesel generator had a spring-loaded shutoff flap in the intake tract before the blower. It was operated by an automatic overspeed trip on the engine's governor, backed up by a big polished aluminum panic button that also operated the linkage to release it manually. We tested the overspeed shut-off (in theory) every 6 months during PMS by cranking up the speed dial on the governor. In reality limited manpower let us actually test it about every 12-15 months. But it was friggin' awesome to choke that huge mass of moving metal down from just over 3600 rpm to zero in seconds... shook several adjacent compartments.

Jim H. "The Navy: It's not just an adventure, it's a ****in' dirty job!"

The simplified inlet "filters" seem to fairly common of marine
engines. I had assumed because the design team thought there was no
dirt on a boat :-)
--
cheers,

John B.

John B. fired this volley in
:

I had assumed because the design team thought there was no
dirt on a boat :-)
--


Well, John, actually, there's not a LOT of free-flying particulates in
the bilges of your typical all-metal boat. There's just nothing down
there that can generate such airborne waste.

In addition, except for the odd insect, there's not much in the way of
particulates floating around over open water in non-industrialized
countries, like 'Nam was.

I cannot remember ever seeing an engine damaged by airborne matter,
except for airborne shrapnel and bullets.

Lloyd

"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote in message
. 4.170...
John B. fired this volley in
:

I had assumed because the design team thought there was no
dirt on a boat :-)
--


Well, John, actually, there's not a LOT of free-flying particulates
in
the bilges of your typical all-metal boat. There's just nothing
down
there that can generate such airborne waste.

In addition, except for the odd insect, there's not much in the way
of
particulates floating around over open water in non-industrialized
countries, like 'Nam was.

I cannot remember ever seeing an engine damaged by airborne matter,
except for airborne shrapnel and bullets.

Lloyd

Snow blower engines don't usually have air filters either.
https://answers.yahoo.com/question/i...1051205AAfJehh

-jsw

On Thursday, September 17, 2015 at 9:17:27 AM UTC-4, Jim Wilkins wrote:
"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote in message
. 4.170...
John B. fired this volley in
:

I had assumed because the design team thought there was no
dirt on a boat :-)
--


Well, John, actually, there's not a LOT of free-flying particulates
in
the bilges of your typical all-metal boat. There's just nothing
down
there that can generate such airborne waste.

In addition, except for the odd insect, there's not much in the way
of
particulates floating around over open water in non-industrialized
countries, like 'Nam was.

I cannot remember ever seeing an engine damaged by airborne matter,
except for airborne shrapnel and bullets.

Lloyd

Snow blower engines don't usually have air filters either.
https://answers.yahoo.com/question/i...1051205AAfJehh

-jsw

Our OMB & gig 6-71's air intake boxes were simple 'silencers', with just enough baffling to (try to) minimize air flow noise. They also served to keep idiots' inquisitive fingers out, I suppose.

Jim H.

On 09/17/2015 08:18 AM, Jim Wilkins wrote:
Snow blower engines don't usually have air filters either.
https://answers.yahoo.com/question/i...1051205AAfJehh

The other factor to consider for those is that there _is_ a lot of
blowing snow (Gee, I wonder where that came from.), and that can
clog up an air filter real quick.

--
Bob Nichols AT comcast.net I am "RNichols42"