Saving Old Seagulls

Please can anybody tell me what quantity of oil is required to fill the gearbox of a Forty Plus.I have just emptied and refilled mine and it took about a third of a litre. Does this sound right? I was expecting it to use much more ie about 1 litre.

All old oil was drained out and engine stood upright as new oil pumped in. Thanks in advance for any replies.

Just fill it till it runs out when stood up

Good heavens it's nowhere near as big as a litre. Externally it is 10cm long by 8cm diam at the widest point. A plain cylinder that size is only 0.5 litres.
It's not a plain cylinder, it's smaller than those dimensions internally and it's half full of bits of mechanical gubbins; gears and shafts, that whiz round in there. I'd be surprised if it held as much as 250cm³ to the correct level.

Quite right Vic - I normally reckon on getting something just over 200 cc's in a Forty Plus gearbox. I know this 'cos I use a calibrated beaker so I will know next time, but promptly forget! Rick

I lay the engine down and put some oil in, then stand the engine in the upright position and see if any oil comes out!
I repeat the procedure until the oil seeps out and finds its own level in the gearbox in the upright position.

Thanks for all the replies. Very helpfull site.