Replacing just one of a pair

[amsuther]

Hi all - does anyone know if will there be any problems if I replace just one of a pair of twin outboards? They are old Honda bf50's, with carbs, and I am thinking about replacemeing one of them with a new bf50 (with efi etc). Will there be any imbalance or anyhing having oldish and new engines paired like that? Anyone done it before?

[yorfuoj]

There should not be major problems !
You have to know the gear ratios of the old and new engines, then you select the right prop for the new one to get the same rpm on both engines.

I had to do it last year, as my cat was waiting for another 60hp engine to be ready, so temporarily running on a Tohatsu pair made of a 60 and a 90TLDI.
The props were a 19" Powertech on the TLDI, and a 25" ali Yam on the 60, allowing to reach a good 45knots.

[amsuther]

Thanks. I'm plugging ahead and creating a new twin rig. We'll see how it goes!

[9D280]

Not looked at the spec'ns but might also be worth checking the weights - you may need to re- stow your anchor for optimal P/S trim!