Osprey 175 Repower to DF140

[Aswaff400]

with the motor trimmed level, can you take a pic with a straight edge on the keel with the jack plate down and one all the way up?

[BMAC1988]

i can try and do that this weekend, the boat is back in the garage and I don't have any tools at home to make the actuators work. you can put a straight edge on the screen on the pics I posted and see about where the plate is in relation to the keel, the motor is level in those pics. its hard to guess where the boat rides on a plane though and without knowing where that is exactly its hard to say for sure where the motor will be oriented.

hopefully I can get some of the wiring hooked up this weekend. still debating on what I want to do about the console/binnacle, the hole cutout for the Rude binnacle is almost double to size of the Zuki one. I wish I could convert the old binnacle to be used on the new motor. 

[BMAC1988]

I got some wiring done today, not much as I would've liked but some stuff cleaned up a little and ran to the console. fuel line is hooked up, motor is powered to the boat batteries, motor wiring harness ran to the console, and the tach is installed and plugged into the factory harness.

got the pics of the bottom of the cavitation plate to the keel with a level, the top of the level is flush with the bottom of the cavitation plate and the motor is sitting level as I could guess where itll sit with the boat on plane.

all the way down


all the way up

[Aswaff400]

judging by the pic, i'd go up 2 holes, which should be an inch for every inch you go back on setback, you can go up to 1/4 inch up. with your jp down the cavitation plate is at a level comparable to  the motor being mounted from the factory with no jp. with a 6 inch setback you can go up 1-1/2 inch

[BMAC1988]

I was going to run it like this first since this put it back at stock height, near-about. During initial testing I can go up a little at a time to see how it performs. I wanna have the motor sit high as I can get away with with the jack plate all the way down right?

[Aswaff400]

Yes, that way you have the most useable travel out of the jp. When running on plane, you want to be able to see the cavitation plate.

[BMAC1988]

 Finally got everything hooked up and I think ready to go for the first trial run.  Trying to get out tomorrow to a  local Lake and run around for a bit.  I've got to get time to get to a place in clearwater and get a replacement steering bleeder tee fitting that I broke off.  FYI hydraulic steering,  narrow splashwell,  Jack plate,  and a motor that is capable of tilting up really far will break off the fittings for the steering. 

This thing purrs like a kitten and runs like a champ.  It's unreal how quiet it is out of the wate,  i bet its next to silent in the water.  Anyway here's a little picture I took of it.  Got a set of custom stickers made for it and they should be here today. 

[RickK]

Thanks for the heads up on the tilt/tee problem. I replaced both of my Tees, I forget where I ordered mine online - maybe Teleflex (I think they own Seastar)

[BMAC1988]

You are correct that teleflex owns them now.  What's weird is not a single place that I called had the replacements in Stock but everybody said that they are common to break. I  had to go to a warehouse to get them.  Also for whatever reason,  there's multiple different ones,  specifically differences in the regular seastar and the seastar-baystar.

 I'm anxious to get it out on the water and get some performance numbers tomorrow   

[BMAC1988]

Got out on the lake Saturday and put a solid 5hr on the new setup.  Overall I am happy with it. I was a bit disappointed at the top speed not being very high but think there could be a tad more to be gained from a better prop,  maybe it's just wishful thinking. 

I started out with a powertech 4blade prop and was amazed at the up on plane ability, it seemed to have a "power band" from 3k-4k rpm that would pin you back however top speed was a whimsy 38mph and best mpg I could find was 5 at around 4k. The 3 blade no name prop I had had considerable more top end and economy once I figured out the correct trim/height on the jack plate.  Both props had considerable porpoising which I believe is mainly due to the added weight and setback of the motor.  Speaking of,  the weight was very noticeable and water does sit in the back while I'm at the helm with a full tank of fuel, having passengers on the front seemed to really help with that and the porpoising.  With just me in the boat and the 3 blade prop I managed 42mph at 6100rpm and bumped 6mpg at 4k rpm cruising at 28mph after considerable adjustment of trim,  Jack plate, and trim tabs,  again porpoising was a big problem.  The boat never seemed to be over powered and was very stable even in a very tight corner. 

Here's a little table I made with some performance numbers.  Keep in mind this was early in the day before the experimenting with motor adjustments.

[wingtime]

I think this confirms that certain hull designs are only going to go just so fast. The faster you try to go the drag from the air increases by the square and I would assume the water drag will be even higher. Aquasport hulls are designed for a particular aplication and going fast just isn't one of them....

Oh and...

 

[akbridge]

Good to hear that it ran good for you.  That top speed does seem a little low.  But then again you do have some extra weight compared to before and you have a T-Top.  What kind of speed were you getting with the old john/rude 90hp?  I think you could get more speed out of it with a fast three blade.  But my guess is that your four blade will give the best overall performance. My 170 had a tendency to porpoise as well.  I added a set of wedges and it did help.   

[wingtime]

My 170 with the 90 Ocean pro will porpoise a bit too. Not sure if it is from the jack plate or the dolfin.

[BMAC1988]

I've got a 14x21 mercruiser 3blade prop that I was going to try but it lightly rubbed on the gear case and I didn't want to risk damaging something.  A guy in Sarasota at Propgods recommended a powertech prx4 prop which id really like to try but that's an expensive "try".  I wish I knew what the specs where on this 3blade prop but there isn't a number to be found anywhere on it. 

I was getting 33-35 with the 88 but it seemed it had lost some power thru the years and the T top definitely didn't help. 

[Blue Agave]

I have a Power Tech 4 blade I'd sell.  Not sure if its the correct pitch for your set up but it is a stern lifting prop and will prevent porpoising, SFS4R19P.  You would also need to re-hub it for the Suzuki, hub available from Power tech.   Let me know if your are interested in trying it out.