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2nd class motor question.

Posted: Wed Jan 08, 2014 4:47 pm
by westcoaster
Hello guys.

There is an exam question i'm studying that goes something like this. " Sketch and Describe an engine driven lubricating pump for a direct reversing engine" does anyone know of a book with a good drawing of such a pump? or worked on a reversing engine that had an engine driven lube oil pump?

thanks

Re: 2nd class motor question.

Posted: Wed Jan 08, 2014 8:03 pm
by JollyJack
Never heard of that one. I know of an engine driven mechanical blower for a reversing engine, but every lub pump I sailed with on a reversing engine was electrically driven.

Re: 2nd class motor question.

Posted: Thu Jan 09, 2014 6:26 am
by JK
see if you can get your hands on a Fairbanks Morris 38 8 1/8 opposed piston engine manual.
The reversible engines have a LO Pump with passages and flaps in the pump that changeover to ensure the flow continues from the suction to the discharge.
I'll have a poke around to see if anyone I know has info.
Actually, the CCGS Tanu has FM engines. Do you know of anyone out there who has access to the CG?

The only ship I can think off hand that actually had them fitted was the CCGS Alert and I think she went to the breaker. I heard a story that the subsequant owners from the CG had engine work done and the repairers didn't know about the flaps and did significant damage to an engine on startup.

Re: 2nd class motor question.

Posted: Thu Jan 09, 2014 7:30 am
by westcoaster
Thanks for the info. I'll dig up a FM OP manual. Maybe a manual from the days of 4 stroke direct reversing engines would have it. Once again I find myself looking for information on equipment that for all practicality, no longer exists.
If the jacket water pump is also engine driven I suppose there would have to be a similar arrangement to maintain flow through the system in one direction, regardless of pump direction of rotation. I've worked on direct reversing engines but like jolly jack said, they had electrically driven L.O and Jacket water pumps.

Re: 2nd class motor question.

Posted: Thu Jan 09, 2014 7:42 am
by EvenKeel
Reversible Gear Pump 001.jpg
Sorry for the poor quality but you get the idea.

Re: 2nd class motor question.

Posted: Thu Jan 09, 2014 7:59 am
by westcoaster
Thanks a million. Exactly what I'm looking for. This is why this website is so great.

Re: 2nd class motor question.

Posted: Thu Jan 09, 2014 9:10 am
by JK
Great, you have it!
When I looked at the answer I realized I had visualized a hybrid between the reversing pump and the blower LOL.
It is at least 20 years since I studied this myself.

Re: 2nd class motor question.

Posted: Mon Jan 13, 2014 6:52 pm
by D Winsor
My how quickly we forget The Daring, Thomas Carlton and the Mikula all had reversible Fairbanks and I believe the Bartlett and Provo Wallace were fitted with reversible 4 stroke Merlees.
Deutz also makes a 4 stroke reversible engine with separate valve block assembly on both the engine driven lube oil pump and on the Fuel Oil Booster pump
Just about every engine built before the advent of electronic controls and electronically controlled injection, even the engines with electric pumps, has at least one reversible oil pump everyone seems to forget about namely the oil pump in the Governor eg. Woodward PG & UG8 Governors. There is a simple drawing in the governor book that shows the check valves and would be easy to reproduce and explain in an exam. Mechanical Governors with an internal hydraulic system such as the Woodward PG & UG8 can be used in any number of configurations and must be able to work in both directions of rotation.

Re: 2nd class motor question.

Posted: Wed Jan 15, 2014 8:19 am
by westcoaster
Thanks. Good point about the governor oil pump.