Seafarer 228G Prop Question

[SwampGrizz]

I have a 2000 Seafarer 228G with a 2000 Yamaha 200 HPDI on it. The prop that's on there now is marked 19M. I am making the assumption from all that I have read on this and other forums that it is a Yamaha Saltwater Series 19" prop. I use the boat with a full tank of gas (92 gal.) and full water tank, with usually two people on board. I noticed that at WOT my HPDI only turns 4700 RPM, and makes only about 38-39 MPH (GPS). What should the RPM range be at WOT, and is this the correct prop for my boat? I'm looking for fuel economy over speed, and it seems to get out of the hole OK, not great, just OK. I have read that if you have too much prop for the motor, it will make it work too hard. Should the RPMs at WOT be more than 4700?

Any and all advice here will be greatly appreciated in advance.

Thanks,
SwampGrizz

 

[bayrat]

Hi..i have a seafarer with a yami 250 with a 151/2 x 17 prop. I turn 6k rpms at WOT.I'm sure that someone with your exact combo will chime in here, but Im pretty sure that your overpropped with a 19' pitch on a 200. That engine should turn about 5500 rpm at WOT. So figure you could pick up approx 400 rpm if you go down to a 17" pitch. You should also see what diameter prop your set up calls for. That could be off as well.

 

[Parthery]

Drop down to a 17" pitch.

You aren't doing your motor any favors if it will top out at 4700 rpm.

Both my 228 (with 200 ox66) and my 226 (with a 200 HPDI) came with the Yamaha 17" SWS prop. Top end on the 228 was 5400 rpm and 43 mph. Top end on the 226 was 5400 rpm and about 38 mph. I upgraded the 226 to a Merc Mirage Plus 17" SS prop. Kept the same 5400 rpm, but the Mirage likes to run trimmed way out, and when I trimmed it out it was almost like an overdrive gear kicked in. Top speed improved to 41 mph.

My 228 did not have a hardtop; the 226 did. That's an additional 600 lbs of weight and a whole bunch of resistance to move through the air...hence the lower top speed.

 

[SwampGrizz]

Thanks for your help!

Does the 19M stamping mean that it's a 19" pitch, or 19" diameter?

SwampGrizz

 

[Doc Stressor]

That would be the pitch.

 

[cgmiller]

I had put a 200 HPDI on a 21 Mako 2 years ago. The dealer put on a 14x18 Rapture prop. It was turning 5400 rpms...I think the recommended WOT was 4500 - 5500...at 4700 you are loading the engine and causing it to burn more fuel than it should and with the price of gas you really need to prop it right. The 228 is not much bigger and with the little wider beam, she will be a little easier to push. You need to check the diameter of the prop. It should be stamped on the inside of the hub along with the pitch, which is definitely 19".