Corm Help Please???50 hp Merc

[sos]

Hi Corm,<br /><br />Thanks again for your previous assistance with my 1965 50 horse Merc. I replaced the points and condenser and there was lots of spark. The engine runs great however it seems the lack top end power/speed.(24 mph at WOT) after manually trimming in all positions. <br />The boat is and old 14 ft Crestliner that is rated for a 40 horse so it should be going a little faster then that!<br /> I'm not sure what the rpms are exactly at WOT as there is no tach, but I can tell it is not reaching its maximum rpm level. Which leads me to my first question is there an after market tach avaliable for this motor?<br />Do you know the Maximum Rated Brake Horsepower and RPM as well ?<br />The prop on this motor is a 2 bladed bronze with a pitch of 17" Could this be the problem ? Do I need a 3 bladed prop or less pitch or both?<br />Or am I totally off track here? You were a great help before and I would greatly appreciate your help once again

<br />Thanks<br />SOS

 

[Yepblaze]

Re: Corm Help Please???50 hp Merc

If you don't get the response here you might like to take it over to a bunch of guys that live, eat, breathe, and poop old mercs.<br /> http://www.pfs-ware.com/kwast/disc_toc.htm

 

[corm]

Re: Corm Help Please???50 hp Merc

Hi SOS.<br />The HP is a little under 50 @ 5200 RPM.<br />I had one on a 14 Alumacraft and ran a 2 blade 13 inch pitch prop @ 5300 RPM alone in the boat. It ran a honest 33 mph with 2 people in it. A 3 blade prop ran 3 MPH slower<br />and did not take off as fast do to the tourqe<br />curve of the motor it likes 2 blade props. Not 17" ones however, It is to large.<br />It is hard to find a point driven tach anymore for the mercs. You won't need one with a 13 in pitch prop.<br />I don't have time to come to the board everyday any more but feel free to e-mail me<br />at either email address.<br /><br /><br />------------------<br />...have fun...corm<br /><br />cubic inches = power<br />power = speed<br />speed = FUN<br /><br />Email me if you need to.

 

[sos]

Re: Corm Help Please???50 hp Merc

Thanks Corm,<br /><br />Your help has been of great value I will try out your advice. Speaking of value any idea how much my bronze prop is worth? It is in excellent shape. <br /><br />SOS

 

[corm]

Re: Corm Help Please???50 hp Merc

$100 - $150 they are on the endangered species list.<br /><br /><br />------------------<br />...have fun...corm<br /><br />cubic inches = power<br />power = speed<br />speed = FUN<br /><br />Email me if you need to.

 

[sos]

Re: Corm Help Please???50 hp Merc

Thanks to Corm and Yeblaze for your assistance.<br />SOS<br />--------------------------------<br />Whatever makes your boat float!