Speed & Rpm

[joeturse]

The prop on her now is a Stainless 14 1/4 X 17.Need to check my tach out.I think that it may not be accurate.

[Mulv80]

I have a 2000 Johnson 150 with full fuel and (2) 225lb adults she'll do 42 mph at 5500 rpm.

[tsubaki]

That prop should be about perfect.
Does the possibility exist that the motor may need to be decarboned? Say with Seafoam or the like.
I just got through outfitting a boat for my daughter and her husband (and the grandkids) with a motor I'd had for years. When I first got the motor it would idle and run good to great but never seemed to have the top end speed I thought it should have, changing plugs, props, etc, never solved the problem. When I put it on the other boat it performed the same till I fogged the carbs a few times and started mixing Seafoam in the fuel. It is slowly improving and turning a little more rpms running wide open than what it used to.

[joeturse]

Seafoam sounds like a good suggestion.I will give it a try.This is my first outboard,I have owned I/Os in the past.
I was pleased with the performance of the motor,other than the low RPMs.
She would jump up on plane fast.Guess you call that a good hole shot.

[tsubaki]

Besides mixing with the fuel, get a spray bottle with Seafoam in it and let the motor get to temperature and spray some in each carb throat, let it smoke and stabilize to run even and do it a few more times after that.
I would expect it will take a lot of doing this at regular intervals in order to remove enough to make a difference.
A daily outing with a good mix of the stuff should certainly help.

[Joker2]

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