Inboard prop size

[Kmodi9]

I will be testing out a new 16-15 with some cup on it this friday, I will let you guys know how it works!

[Gary Hill]

I tried MILES OFFSHORE (Craig's) prop when I first put my motor in and could only turn 4200 rpm and the four barrel did not open all the way, the 17 x 16 gave me the 4600 that I was doing. I had a new tach and Meercusier make a digital for aboy $75 that I have to compare RPM's which gives a accurate reading, it wraps around one spark plug wire and ground. I have had trouble in the past with a Tach reading the wrong RPM's.

[classictrade2]

Just got a call from the mechanic and he is finished putting in the new cutlass bearing. I may have to dodge rain drops this weekend but I plan on seeing what the new cutlass bearing does before I mess with the prop. Normally this would not make a difference but the cutlass was in horrible shape. Vibrations were bad. Also, I am not 100 % sure the tach is all that great either. I still have lots to do, but I do love the boat. SEACRAFT FOREVER!!!!!

Arthur

[riprunner]

I have the plug in mercruiser fuel management system with all the goodies that go along with it, but I have never tested that tach against the regular RPM tach. I'll check it this weekend to see if there's a difference as well. I too am going to check wot RPM's. Thanks again for the help guys!

[CHANCE1234]

It sounds like all you guys are cruising at more RPM's than me. I tend to cruise around 26-2800 RPM's. Current depending i make about 17-20 knots. I don't know exactly what size wheel i am spinning but i don't have any viberations. Does this sound like i am not running her at the best RPM range? I have a 1995 mercruiser inboard 260 hp, 350 small block chevy. Any thoughts??

[classictrade2]

Chance 1234

I have that exact engine in my other boat and I find that the best cruise is 3150 rpms, just before the quadra jets kick in.

Arthur

[riprunner]

Well I found out that my Mercury computer does read about 2000 RPM's lower than the reqular tach. Unfortunatly while moving from one spot to another the ethenol issue I've been having all season finally got me. I got a tow back to the dock and it looks like the brand new tanks may have to be drained.