225 Evenrude vr0 start up smoke and fuel consumption.

[jurgenscraft]

Good evening all.even though our 225 vro motor is in good condition (recently serviced and tuned ) but it smokes quite a lot when started in a test tank, the vro has been disconected and we run a straight 50:1 If fuel is kept for a few weeks, will the petrol evaporate off making the remaining fuel even more oil rich causing this excessive smoke, secondly what sort of consumption can be estimated from this motor, mounted on a 20 ft deep vee cabin boat using a 14 1/2 x 21 pitch propellor we are able to hit 5300rpm to 5400rpm quite easily.we have been told that the VRO supplies less oil at idle and very low rpm ? maybe that is why the motor smokes at startup ?
Kind Regards William Wright

 

[angus63]

Re: 225 Evenrude vr0 start up smoke and fuel consumption.

Fuel evaporates and oil doesn't. After sitting in the bowls for a while the fuel evaporates and leaves a very concentrated mix in the bowls. Startup tends to puff blue for 5-10 minutes until the 50:1 mix absorbs and burns the heavy mix out of the bowls. Completely normal.
You can expect to burn 20-22 gal per hour at wide open throttle. Probably 12 gallons per hour at 3600-3800 cruise. Varies for all boat types but this is a pretty acurrate median usage.

 

[jurgenscraft]

Re: 225 Evenrude vr0 start up smoke and fuel consumption.

Thank you very much for the reply to my questions, A friend of mine said that 10%of hp in gallons US per hour at WOT was a good guide and this ties up with what you have said,
thanks for the help.William Wright

 

[angus63]

Re: 225 Evenrude vr0 start up smoke and fuel consumption.

You are very welcome and stay clear of the jumping Great Whites!!!! I love shark week onthe Discovery Channel!!!!!!