85 HP Evinrude Question

Hi Guys,

Just after some advice from the all knowing combined intellect of the group.

I recently purchased a Chivas Thunderbird MkV that is fitted with an Evinrude 85 hp motor that was manufactured in 1975 http://www.ausfish.com.au/chat/images/smilies/cwm4.gif.

The motor is is excellent condition for it's age and has plenty of grunt but running at about 15 knots it uses 25L/hr which seems a bit much.

Is the fuel usage normal and if so should I stick to this motor or get another one? If replacement is warranted what would be a suitable size motor and price ?

Thanks in advance.

AG http://www.ausfish.com.au/chat/images/smilies/cwm11.gif

might help us mugs if you say how heavy that boat is, what diameter and pitch prop, and whether 15 kts = wide open throttle, half on the plane, etc etc.

Gurus will know the answer on the info you have provided, no doubt.

Thanx Fishtime for replying.

I thought that the old Chivers Thunderbird was a boat common enough to be known to most ,sorry http://www.ausfish.com.au/chat/images/smilies/cwm6.gif

In answer the TBird is 18 foot 6 fibreglass and is HEAVY.She is capable of 35 knots at full throttle so at around half throttle it uses 25L/hr.

Have no idea of prop pitch but the motor etc are standard issue for the old girl.

Thanx again