mercruiser 4.3 V6 petrol consumption?

[pete1987]

Quite a bit, obviously.

But fitted to a 28' sports cruiser what are 2 of these lumps likely to burn at displacement speed of 5ish knots? I realise these will be frightening at WOT but just wondered if anyone has experience of running these motors on the river. They are 1990 vintage and the 205hp variant.

Thanks

 

[MapisM]

I'd be surprised if they would burn more than 10 l/h in total.

 

[rwilson]

fyi 8.5-10 lph for 2 x 250 modern Yamaha outboards on 10m boat. Perhaps a little more, say 15/17 for the mercruisers if they are on carbs? Could always just use one engine to free the consumption down?

 

[landlockedpirate]

28ft Wide body Regal on the Thames with 2 x mercruisers (4.3L carbed) averaged 12lph. Anything faster than this was frightening.

 

[Bbroomlea]

Our old S24 had the 4.3 volvo equivalent - on Windermere over three seasons it averaged approx 1.8gph. That included mostly pottering at 5kts but some much faster sprints as well on occasions

 

[pete1987]

So looks like 3-4 gph between both engines. That's still a lot for a small boat. Thanks for the info.