I just got a 2014 mercury 4s 150 h.p, (2B042842) that came with a Rev4 (4bladed) prop. Boat has terrible hole shot nd at 5850 rpm only gets to 50 mph . I have a smartgauge also. Has a hyd. jack plate and I tried all the way down, and diffencet places on plate. Water pressure is 6 or 7 at idle ang goes up from there . I was told maybe a Bravo 4S 21p ny throughts would be appreciated THANKS
prop does have 3 of4holes open
I also have set up very close to yours. First thing I would do is plug all 4 vent holes. That may cure your problem(s).Originally Posted by mark482vs
You don't say what pitch the Rev4 is but 23 and 21 works best on my boat. I run Trophy Plus.
I use the 23 the most but sometimes run the 21 if I know I will be in need of best hole shot because of big load.
Sorry it is a 21 p wouldnt that hurt hole shot more? (PLUGGING HOLES)
Most 4strokes have enough low end torque that the don't need prop ventilation for hole shot. You may have too much ventilation causing too much slip at takeoff. That's why most of us can run solid plugs.
No just the opposite........with 4 stokes more holes plugged........with 2 strokes more hole open......rule of thumb for start place.
THANKS everyone! I understand motor on last Ranger I just sold but this thing is a different animal . Hope Mr. Don answer my questions.Also hyd. jack plate is confusioning me as for start point. shoud I bring plate up to 3.25 ptp
I would plug all holes and start my journey on what works best with hyd. jack plate down. It is easy to try hyd. JP in different heights to see if better or worse.
My 300 Pro XS 4S on a Bass Cat Lynx most definitely benefits from added ventilation. If I plugged the holes it would lug badly.
Not disagreeing but just curious have you tried it with all 4 holes plugged? From what I read most 4 stroke folks intend to plug all or most of the prop holes.
You are running a lot of horsepower and I have no experience with that. My experience is with 150 HP.
I have run a Bravo with 4 of the 8 holes plugged, I opened 3 up (large plugs) and the hole shot was much, much better. Actually needed more venting than with a 250 2S on my Cougar, same prop. The Lynx is a bigger heavier boat and it was loaded.
Plugging holes seems to work better on the SHO, the Merc with its smaller pistons although more of them does not turn a prop as well without some help. On a heavy load anyway.
If we could, what BOAT is this engine on (need a better picture of what was rigged and sent out with a Rev-4 on it)...
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
2015 Ranger 118c , 150hp 4s merc and two 8ft talons
See if you can find someone that will let you try a 21P Bravo-1 FS or a 21P Tempest Plus.
IMHO (for what it's worth) that battleship-prop didn't really have a business on that hull.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
+1 my partner has the same motor and it came with a 23p tempest and it cant turn it.
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