Tried a 4 blade for the first time.. IL6 Merc 1350

stant1man

Petty Officer 1st Class
Joined
Jul 21, 2004
Messages
360
Got this Mach 13.5 x 18 four blade prop on my boat... It didn't seem to work <br />even half as well as my 13 x 18 quicksilver 3 blade?<br /><br />It is ported and looks really fancy.... Am I missing something, should this <br />prop not give me better holeshot. With this on, my engine revved to 5200rpm <br />and my 3 blade revs to 5800rpm.<br /><br />Not only that but when I went into gear it really seemed to thump as though <br />the prop was much heavier.... Which it is but...well...<br /><br />What do you guys recon?<br /><br />Cheers<br /><br />Stan
 

phatmanmike

Captain
Joined
Oct 24, 2003
Messages
3,869
Re: Tried a 4 blade for the first time.. IL6 Merc 1350

stan i put a 4 blade stainless on my 225 johnson v6 a few weeks back. it gave my motor a higher top speed and a bit better hole shot<br /><br />my normal prop is a 15x 17p 3 blade aluminum<br /><br />my test prop was a 4 blade stainless 19p, im not sure about the diamater though.<br /><br />i know this isnt an inline 6 merc, and i know my boat is about 4 thousand pounds heavier than yours, and i know that its about 100 hp more, but im sure its usefull none the less.<br /><br />by the way stan, i just got this for my inlne 115:<br /> http://cgi.ebay.com/ebaymotors/ws/e...d=1,1&item=4576893409&sspagename=STRK:MEWN:IT
 

walleyehed

Admiral
Joined
Jun 29, 2003
Messages
6,767
Re: Tried a 4 blade for the first time.. IL6 Merc 1350

Stan, with the same pitch, larger diameter, it's going to drop in RPM and so is your speed unless you raise the engine up on the transom, but I still doubt we'll get the RPM back, and expect no gain in speed over your 3 blade.<br />On some boats, some 4 blades lift the stern too much forcing the bow down and actually lose speed...this may be the case.
 

WillyBWright

Fleet Admiral
Joined
Dec 29, 2003
Messages
8,200
Re: Tried a 4 blade for the first time.. IL6 Merc 1350

Old inline Mercs don't swing 4-blades worth a crap. But then remember, back in the day the perf props had 2 blades. Got a hacksaw? ;)
 
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