Low WOT. I think

[TeamGroot]

Hey everyone, thanks for your assistance. I have read so many of these forums and I'm confused about my prop size.

I have a 1990 searay 250 weekender. It has a single 5.7 Mercruiser with alpha one outdrive.

My current WOT is 3900-4000 at around 30MPH

It is a dog coming out of the gate and my family likes to go tubing. I was thinking, "lower the pitch of the prop, increase the RPMs, better hole shot". Then I looked at my prop. It has a 15 pitch prop. Most forums talk about 17-23 pitch props.

Can I go lower than 15p? Do I have something else happening? Is my 26' boat too big for tubing?

Thanks again for your assistance.

 

[wiigelec]

Are you sure your engine is in top running condition? Good compression, oil, spark plugs, timing etc...

 

[Faztbullet]

Big diameter....small pitch ...trim tabs=

 

[Scott Danforth]

your current WOT is low

need to know if your engine is healthy (do a compression test as a minimum)

then need to figure out what your current prop is.

then after you do those two things, can we make a determination.

 

[Old Ironmaker]

Something is amiss. 4000 RPM wide open is sluggish to say the least. Start troubleshooting with the thing that gets any machine moving, the engine. Then work from there. The prop is not where to start in my opinion. You can spend a lot of money and time throwing darts at the multiple of possible problem targets only to find out you aren't firing on all cylinders.

 

[Faztbullet]

That hull digs a hole in the water and has to push itself over its bow wave...all the weight is in the rear. Tabs is a great investment on these.

 

[QBhoy]

You think the tachometer is accurate ? At 30 mph and those rpm and a 15” pitch prop..you’re doing well really. I think perfectly propped and all else being well, that set up would max out at about 35 in perfect conditions. So to be 800-1000 rpm off the top of the usual rpm range and still doing 30 mph...if you know what I mean. Is the prop defo a 15” pitch and not diameter ?

 

[TeamGroot]

Thanks everyone, I'll be checking the engine out. I just had the engine coupler replaced so I'm hoping the engine is good. Ugh.

Faztbullet do you recommend I lower the tabs all the way before I take off with a tub in tow. New to the game and still learning what's best.

I appreciate your thoughts and ideas. This forum has been incredibly helpful.