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Un-Related Submarine Diesel Engine Question

jon_allen

Regular Contributor
Hi Guys

I have a question which is not related to this forum.


There are some very, very knowledgeable people who contribute to this forum who likely have the answer.


Question:

When viewing old movies and footage of diesel subs at sea, the motors have the valvetrain exposed (no valve covers) and crewman are manually oiling the valve train. Why is this?

Clearly, pressurized lubrication and valve covers were being utilized in automotive applications during this era.


Thank You

Jon Allen
 
There is a totally different mind set here.--------# 1 is you can see if anything is going wrong.-----Fix it without having to remove covers.------Reduce cost.-----There things were designed to be reliable for a short duration.-------And they did dot have to pay the crew either.
 
.................
Question:

When viewing old movies and footage of diesel subs at sea, the motors have the valvetrain exposed (no valve covers) and crewman are manually oiling the valve train. Why is this?

Jon, I was actually given a chance to look at an old diesel marine engine once.
I don't recall what year is was, and it was not a submarine engine.

These were huge diesel engines that turned very low RPM.
I believe that the valve train components were exposed because of how large these components were, and for easy access.
The oil system for the valve train was not pressurized.
Each friction area had an drop sight oil feeder (aka drop sight gravity feed oiler) above it that dripped a pre-determined amount of oil onto the friction areas.
(yes, I Googled that for the proper names)

The oil drop sight feeder required periodic re-filling, so when you saw a crew member oiling these, he was likely re-filling the oil chamber.














Clearly, pressurized lubrication and valve covers were being utilized in automotive applications during this era.

I'm not sure what automotive era aligns with this submarine engine.
Many of the first gasoline internal combustion engines were flat head engines and did not incorporate a fully pressurized oiling system in lieu of a splash system. With the splash system, each connecting rod cap had a dipper/scooper (so to speak) on it that picked up oil from an oil-filled trough.
The oil was then forced into that bearing journal and onto that cylinder wall and other internal components.

(I had to Google this one) .... it wasn't until around 1900 when the fully pressurized oiling system started being used.



Fun topic!
By the way, what movie were you watching when you saw that engine?
 
Racerone and Rick

Always wondered about this.

My Grandfather was a mechanic in the Navy.
He served on the Sperry which was a sub tender during Ww2. I never got to ask him about the exposed valvetrains.

Rick ,


I can’t remember which movie I watched which showed the oiling of the rockers

I think it may have been Das Boot.

Great Movie.

Thank you both

One more item I can scratch of off my bucket list!

Jon Allen
 
Many diesels engines before WWII had exposed rockers. They were manually oiled once an hour. These engines were slow turning with a maximum rpm of about 300. Atlas, Washington Diesel and others made into the 1950s required manual oiling. Ships, tugs and fishing boats of the time had an engineer and it was just part of their job. The oil used wasn't like motor oil, but thick and sticky. I grew up running those kinds of motors. The modern US subs of WWII had engines with rockers (under covers) that were pressure lubricated. Winton Engine Co. - later a GM division and in 1937 became the Cleveland Diesel Engine Division of General Motors made many of the sub engines. Fairbanks-Morse also made many engines. FM engines were opposed piston engines with no valves, just ports. If you saw rockers being oiled in a US sub, it was probably from WWI. S boats, the last class of WWI subs, made war patrols early in WWII. R boats and older subs were used as training boats at the sub school. After WWI subs had fish names and an S number. Up to WWI subs started with A-1, etc. Each new class went thru the alphabet ending with the S class. There was a third engine installed in WWII US subs, Hoover, Owens, Rentschler Co. A licensed German design. They were a failure and in the middle of the war, the engines were cut out of the subs that had them and replaced with Cleveland or FM diesels.
 
Hi Lepke

Thank you so much for the in depth descriptions of the various sub motors. I
now have a better grasp on the topic.

There is no better source of info than what is available on this site.

Thank you

Jon Allen
 
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