Prop on a 21 SE w/ 150 HPDI

[Regulate It]

First let me say this site rocks, great info, great group of guys. Thanks for all the past and future info from a Parker newbie. I have owned a lot of boats and after fishing on a guide buddies Parker 21 SE I put it at the top of my list. I finally got the boat 5 weeks ago (it was a negelected P.O.S. :x - not sure why some people let things go like this), put a ton of blood, sweat and $$ into it making it my own (e-box, new electronics, filled a million holes the PC method - thanks Porkchunker) and finally got her on the water yesterday and got some blood on the decks. Ran 87 miles roundtrip, boat ran like a top, fished skinny water on both sides of mid-bay in the Chesapeake and the boat completes me! LOL!

Except for blowing my second tire on the trailer (all four tires were were rotted) was a perfect day.

Now that I'm done with my Jerry McGuire moment, I could use some help with the propping. I ran the boat with 60 gals of fuel, 2 guys and gear and boat performed great at 4000 rpms - good fuel burn and plenty of speed. But I opened it up at the end of the day to see what it could do and regardless of trim attitude of motor, adjusting tabs to the point of eliminating them from the equasion etc. I could not get it to turn over 5000 RPMS @ 38 mph. I am not a speed demon, but shouldn't I be able to hit 5600 RPMs?

Not sure what prop size is on the boat or how to tell - I thought it was stamped on the prop?

Any suggestions or info from current 150 HPDI owners on what size prop they are running.

I am in Falls Church Virginia and anybody with knowledge of a local prop shop would also be appreciated.

 

[Brad 21se]

I have a 15 pitch Michigan SS prop on my 21se and turn 5500 WOT. My Yamaha 150 (carbed) originally had a black Yamaha SS prop (17 pitch) and it would just touch 5100 WOT. Both props performed well, but the 15P got me at the upper range of the WOT spec for my engine and also it's more responsive. WOT on GPS is 41mph with the 15P prop.

The diameter/pitch should be stamped on the prop hub/side. HPDI's are also notorious for losing top RPM due to VST filters being partially clogged, fouled plugs, etc.... I had one on my last boat and chased upper RPM issues even though the engine ran great otherwise.

I think most 21se's came rigged with a 17 pitch prop.

 

[Regulate It]

Thanks for the reply. Maybe a dumb question, but your prop is 15 x 16? Would you mind giving me the name of the shop/vendor where you got it? I am pretty sure what I have is the original prop.

I had the motor gone over top to bottom by a certified yammi mechanic who serviced it since new. They replaced an O2 sensor and I had them do 100 hr service but other than that they said it was money. I have heard about the filter issue in the past. Thanks for the reply.

 

[Brad 21se]

The prop is a Michigan Apollo SS - 14 3/8 x 15P. It uses a Flo-torque hub insert, which makes it universal. It's a decent prop for the $$.... I am using it since I had it from my last boat which also had a Yamaha. The HPDI I had ran a Yamaha Saltwater Series prop that was 15 1/4 x 15P. That engine was a 200hp.

Good luck and let us know how it turns out

 

[markman03]

If you check with Parker I think they are going to tell you to run a SS 14 1/2 x 15P. I had a few questions about my 2110 with a 150 HPDI and I was told that the Yamaha Reliance with that diameter and pitch was what performed the best. I found one with 2 hours on it for a third of the original price. Brought my RPM's up to 5200. The last time I read the manual it stated that the 150 HPDI should run between 4500-5500.