prop time, 18 cc 150 johnson
 

so ive got the motor sitting back there looking all shiny and nice, now comes the tricky part; prop time. got a simple 3 blade prop (17" i think) on right now, probably going to have to go bigger. boat has a 48 gal fuel tank and a homemade (from wood=heavy) 40 gallon baitwell so she is on the heavy side. rarely fish w/ more than one other person for longer runs, if shes loaded w/ people we're just booze cruising. i tried searching old threads and didnt find much. motor is a 150 hp carbed johnson. oh and for all you guys much smarter than me that kept drilling the weight to power issue into my head, she tips the scales at 391 lbs. also, any of you SC guys know of a good prop shop in charleston area where i could try them before buying?

Re: prop time, 18 cc 150 johnson
 

try the 17 first of course which will get you started at least. I will guess at 19 as you said kinda heavy but I ran a 17 on a 115 so a 21 may not be out of the question

Re: prop time, 18 cc 150 johnson
 

22-
I have a 1990 18' running a 1990 Johnson 150.Prop is SS 15x17 Michigan. Max RPM is 5200 at 42 MPH one man, 1/2 tank.I probably should drop to 15x15 to get higher wot RPM under greater load. Hope this helps. Any suggestions on this matter are appreciated.

Re: prop time, 18 cc 150 johnson
 

Looking forward to hearing the test results and seeing pictures.........That boat will fly

Re: prop time, 18 cc 150 johnson
 

thats just fine, them rudes don't like 5800 much, it ain't a Merc

Re: prop time, 18 cc 150 johnson
 

dropped her in the water last night for initial breakin period. ive always known about the term "holeshot", but having always run ancient motors never really known what it was. all i can say is im glad i had my back rest in the leaning post or my ass would have somersaulted backwards! like an idiot i forgot my gps but ill bring it out later this week one evening and get some #s up. prop adjustment will definitely be necessary. went out w/ a barebones load last night (1 person, no gear at all, 1/2 tank gas) and barely broke 5000 rpm, using every but of trim/trim tabs i could muster. even w/o gps speedo i can tell i wont see much dropoff in top end speed from the old merc to this motor. she was flying at 5000 rpm(mid 40s?).

Re: prop time, 18 cc 150 johnson
 

I stand corrected - Mike says thats a 60' motor and it should with a medium load he wants it at 5800. Also double check the prop he thinks you might have a 19, he wasn't sure.

He also has a 200 and 225 '07 Etec's - BRP has a bunch of new rebates and a 5 yr warrenty they released at the dealer meeting, he didn't attend so we would have to call Mario for the scoop. He also has an '03 in the box DFI with 5 yr warrenty for 9500

Re: prop time, 18 cc 150 johnson
 

Egg
Thanks for your input on this matter. I just found and purchased a SS 15x15 Michigam on craigslist. I will run it shortly and report back.

I understand your concern on over reving the old girl.Hate to blow her up and be forced to get a new engine. ;)

Re: prop time, 18 cc 150 johnson
 

The 90' motors are much better around 5100 to 5400, the 60' motors are similar the to the Merc 60' and will take and like a little more RPM - the real guy to talk to is Mike Phillips at American Marine, been a Rude dealer for over 30 yrs and can just listen to a motor and know whats going on. If you have any Rude questions whether maintaince or figuring something out he'll help on the phone- feel free to call him at 727 938 9796 just tell him where your from and he'll bend over backwards.

Those 90' motors are like Harleys lots of guts but don't like alot of RPM. They also like to be decarbed regularly, have a habit of getting carbon in the ring glands and hanging one. Not sure which your is, they apparently built 60' and 90' 150's

Re: prop time, 18 cc 150 johnson
 

rhody, looking forward to hearing what that prop turns for you. ill be getting out either today or tomorrow and will get some initial #s up w/ my 19.

Re: prop time, 18 cc 150 johnson
 

Just got back from the test run with the 15x15 prop. Conditions were a little choppy.

4000 rpm 28.8 mph
5000 rpm 35.7 mph
WOT 5400 rpm 39.5 mph

Egg, thanks for the contact and the 90'/60'info. My 150 is a 90' block.

I think I will use it. Only lost 2.5 mph but the engine will be under less stress with a heavy load. 39.5 or 42 mph is too fast under most conditions in an 18' boat (for an old man).

Re: prop time, 18 cc 150 johnson
 

Makes them much easier to drive at cruise speed in heaveier seas as its not trying fall off plane all the time. Numbers look good

Re: prop time, 18 cc 150 johnson
 

remembered the gps yesterday. 30 mph at 3300rpm, 40 mph at 4600. wouldnt turn more than 4600 yesterday w/ full tank, girlfriend, and heavy cooler on board. definitely going to have to go smaller (prop) but not a bad starting point.

Re: prop time, 18 cc 150 johnson
 

Check what you have- 17/19 as Mike couldn't remember what he gave you but thats hauling at 3300. You'll lose a little of that going down in size but it will be drivable. I bet its a 19 and I would have thought it would swing one one.

Re: prop time, 18 cc 150 johnson
 

"w/ full tank, girlfriend, and heavy cooler on board."

Justin

Excellent positioning of the word "heavy" in your sentence. A couple spaces to the left and it would not be pretty at your house!! ;) Ya can't be too careful!

Re: prop time, 18 cc 150 johnson
 

i know. i get enough eye rolls from her seeing me either on csc or charlestonfishing.com. she weighs all of 115 lbs, cooler probably weighed 75. it amazes me the difference in top end rpm w/ different weights in the boat. went out for a quick trip yesterday and she turned 5150 again (skeleton crew; me and nothing else on board). probably should just use sand bags to simulate weight where it goes for prop tests...

Re: prop time, 18 cc 150 johnson
 

This is interesting.
I have 2002 Johnson 115 on my 1989 18CC and am running a 18 pitch Cyclone 4 blade. I'm getting about 36-37 MPH @ 5400 WOT with 3/4 fuel, another person and typical fishing load.
This past weekend with 3 people total, I was running 26 mph @4100 but it was a solid 2' wind wave so tabs were being used.
I did add the 6" jackplate and the performance/speed seems a little better, but I do get more bow lift.
Can't wait to try it out with a light load, I should hit 40 MPH.
BTW, my neighbor who fished with us this weekend (he has a 21' Seahunt) couldn't believe how nice my little 18 ran and never got him wet :D

Re: prop time, 18 cc 150 johnson
 

I've been in touch with Skip's Propellers lately and have tried several props and exchanged them. They are on Cross County Road in North Charleston. With my old Crossflow 150 on my 18' and 2 people I am seeing 47 mph GPS and 5500 RPM with OMC 14.75 x 17 pitch Viper. Trading in for 14.25 x 17 pitch Stiletto this week to see what happens. Looking for 5800 and 50+ MPH solo and no load.

Re: prop time, 18 cc 150 johnson
 

Hey! You gotta check out the 13 3/4 prop on Ebay! 15 bucks or something ridiculous. Ends tonight but does not state amount of splines. Sounds like what you need. www.continuouswave.com (Whaler) under Marketplace. Check it out! Part II.

Re: prop time, 18 cc 150 johnson
 

rob, thats exactly what i would like to be turning. i spoke w/ brooks oswald (oswald props on JI) and am going to start trying them out this weekend. would like to see 5800 empty boat, 5500 loaded down. also, got transom hatches installed yesterday; the good news is they look amazing, the bad news is i cracked one of the old ones trying to remove the hardware. give me a call when you get back into town and you can come grab them...

Re: prop time, 18 cc 150 johnson
 

bet the heavey cooler was up front ??

Re: prop time, 18 cc 150 johnson
 

cooler was in stern. got a 15x16 prop now. went out today, 5300 w/ 3 people and heavy load. no gps today, like I-95 out there so i didnt really push it. had some yahoo almost broadside me (in a no wake zone). his kid was standing up in front of him. he got about 8 feet away before we started shouting. he finally jerked the wheel to avoid hitting me about four feet away, gave me startled thumbs up, and continued on (throwing a wake). got to love saturdays in the summer. ill try and get out early in the morning for some gps tests.