hellllpppp 1980 evinrude 100

[cabarkeep]

help ... im contemplating purchase of a 1980 boat with twin evinrude 100's on it ... the engines seem to run smooth however the boat seems way overpropped ..takes wayyyyy too long to get on plane and out of the hole ...

wot on plane in a lake the rpms were only 4200 .... getting out of the hole 2400 until we were up on plane ...

my question is ... what is the correct size props for this size engine?

its a 20' robalo center console so its a pretty heavy boat ..any suggestions???


helllppp

 

[jimmbo]

Re: hellllpppp 1980 evinrude 100

The reccommended rpm range for that engine is 4500 - 5500. You need to gain 1300. So using the standard 200 rpm for each inch of pitch, you need try props that are 6 or 7 inches less in pitch than you have now. What props are on there now?

I take it for granted that the numbers you gave were with the engine trimmed out as far as possible?

200hp with 2 props, the boat should still get on plane pretty quick even if it is 20 ft long.

Have the engines checked over before any purchase, being 28 yrs old they might just be worn out.

 

[steelespike]

Re: hellllpppp 1980 evinrude 100

Without prop demensions it is difficult to know if it is props or an engine or boat problem.Unless you need a back up in case of failure I would go with a single engine set up.A lot easier on maintenance and even with a single 200 I think you would be ahead on GPH(gallons per hour) and transom weight.