LPW 4 Engine oil change with in very cramped conditions

[Pedro]

https://flic.kr/ps/45x3rC
Hi all
I'm sure someone out there can help me with this.
I've recently bought a decommissioned oil rig lifeboat, and I would like to carry out the first engine maintenance ASAP. I have the new oil and (I think) all of the filters, but cannot drain the existing oil the way the manufacturers recommend due to the fact that
1. I am not a contortionist.
2. I am not 2 feet tall.
3. My arms are not 6 ft long and with several elbows
The guys who take care of these boats in the offshore rigs might have special bodies or hidden techniques, but I do not.
Accesss to the nut at the bottom of the engine is therefore beyound impossible for me, so please let me know of the best alternantives you can think of.
It's a Lister Petter LPW 4 cylinder 40 bhp built in 2007 also known as Canal Star or Alpha, but I suppose the issue would be very similar to any LP fitted in such a ridiculously small engine bay.
Drain the oil with a pump via the dip stick opening or is there a better way? Also, please let me know of the best way to drain the oil out of the gear box.
I uploaded a few photos to flickr at https://flic.kr/ps/45x3rC , but please let me know if you need more details.
Thank you so much in advance
Pedro

[Diesel Engineering]

Normally any Alpha series engine marinised by Lister Petter would have been fitted with a sump pump for removing the oil. The engine you have has been marinised and modified by Sabb in Norway. Lister Petter would supply the engines to Sabb who would do the necessary modifications to allow the engines to meet the relevant specifications. The engine was designated L4 by Sabb.

[Pedro]

Would you know how a "sump pump" on a Lister would look like and the location?
My google search for the term was inconclusive and I cannot find the term on the Lister drawings.

[old seagull man]

Usually there is some kind of hand pump fitted, to do the oil change and a valve you open so the pump drains the sump.
This is what mine looks like. Should say Drain pump, typing without glasses, at 3am. Never good.

[Pedro]

Thanks.
There is such a pump. I uploaded a photo of it just in case someone has a similar question in the future.

https://flic.kr/p/2qCk9af

[Diesel Engineering]

That does appear to be a sump pump in your photo. There may or may not be a valve on the bottom which needs opening. Also run the engine up to temperature first, it will make pumping a lot easier