The MRI reports that came with the boat from the factory show both props have identical diameter and pitch. However, the prop chart on the SR website shows the RH prop should have a pitch of 18.5 inches instead of 19. Is there a good reason why SR would have put identical sized props on my boat against their own recommendation. I remember Frank Webster on another thread said one prop has less pitch than the other to account for the slightly different transmission ratio. Is my boat the exception or do a number of other 320 owners have identical pitched props?
SR put Same Size Props on My 320
- Thread starter 320Bob
- Start date
Alex F
Well-Known Member
- Nov 14, 2006
- 9,166
- Boat Info
- 2005 420DB with AB 11 DLX Tender, Raymarine Electronics (2x12" MFDs) with Vesper AIS
- Engines
- Cummins 450Cs, 9KW Onan Generator, 40HP Yamaha for tender.
Hey Bob,
Instead of guessing have you considered asking SR about this? Just shoot them an email and see what they say. You might end up with a free prop (although, very unlikelly).
Instead of guessing have you considered asking SR about this? Just shoot them an email and see what they say. You might end up with a free prop (although, very unlikelly).
Southpaw II
Active Member
My understanding is that the props will be identified as identical, but one is slightly different to compensate for a slightly different drive ratio between the port and starbord drives.
Alex,
I will first try to work through my dealer who sold the boat to the previous owner and now to me. If they won't contact Sea Ray on my behalf, then I will go to them directly.
Southpaw,
One prop has a wheel average pitch of 19.060" while the other is 18.970" so they are for all practical purposes identical. The dealer had someone up in storage Wednesday and he check that the two props are identical in diameter and pitch according to how they are marked along with one being right hand and the other left hand.
Now on a 2006 340 with the same engines as my boat the prop chart lists RH and LH props with identical pitch but for the more common 8.1L engine the pitch is LH 21.5" while RH is 21.0". For a 320 with 350s, the props are identical to what the chart says for mine.
I posted this thread to find out if this was common amoung 320 owners or was my boat the exception. If the latter then perhaps I would have a stronger position with Sea Ray to get a replacement through my dealer.
I will first try to work through my dealer who sold the boat to the previous owner and now to me. If they won't contact Sea Ray on my behalf, then I will go to them directly.
Southpaw,
One prop has a wheel average pitch of 19.060" while the other is 18.970" so they are for all practical purposes identical. The dealer had someone up in storage Wednesday and he check that the two props are identical in diameter and pitch according to how they are marked along with one being right hand and the other left hand.
Now on a 2006 340 with the same engines as my boat the prop chart lists RH and LH props with identical pitch but for the more common 8.1L engine the pitch is LH 21.5" while RH is 21.0". For a 320 with 350s, the props are identical to what the chart says for mine.
I posted this thread to find out if this was common amoung 320 owners or was my boat the exception. If the latter then perhaps I would have a stronger position with Sea Ray to get a replacement through my dealer.
trit21
Active Member
Charts say they are the same, then they are the same. Mine are identical for all intense purposes. I had them prop scanned and adjusted as I needed.
Then why 2 years later did Sea Ray change their mind and specify a different pitch for the RH prop for the same engine as yours? Do we have slightly different transmissions for our V Drives?
You mentioned that yours were adjusted, out of curiosity what did they adjust and why?
trit21
Active Member
Load your boat how you want to run it with all the stuff you bring, people, full fuel water etc. Run your boat and determine if it reaches RPM at WOT. If it is too high or low, the company that did my prop scan can adjust the props so you achieve the correct RPM at WOT. When SeaRay props the boats, they are pretty much empty, no stuff so you MAY get a slightly lower RPM at WOT than what you should.
www.propscan.com
I found the company in my area and it took out all the vibration and made the boat run more efficient, (Boat and efficient yeah right) but you know what I mean.
Why did SeaRay change it? Who know and as far as your concerned why would you care? Does your boat run correctly, throttles and RPM pretty much match? Did SeaRay change something in the trans or the maybe Mercury in the engine specs. I don't know. Is all I know is that my boat has the same props on each side and RPM and throttles are in the same position relative to each other and the boat runs good.
Added notes: Maybe SeaRay changed the prop manufacturer. Not sure if that would do it or not? Wouldn't think so but then again, I am not sure.
www.propscan.com
I found the company in my area and it took out all the vibration and made the boat run more efficient, (Boat and efficient yeah right) but you know what I mean.
Why did SeaRay change it? Who know and as far as your concerned why would you care? Does your boat run correctly, throttles and RPM pretty much match? Did SeaRay change something in the trans or the maybe Mercury in the engine specs. I don't know. Is all I know is that my boat has the same props on each side and RPM and throttles are in the same position relative to each other and the boat runs good.
Added notes: Maybe SeaRay changed the prop manufacturer. Not sure if that would do it or not? Wouldn't think so but then again, I am not sure.
Last edited:
After several emails with Sea Ray and talking to my dealer it's a combination of conflicting information and two different prop suppliers for 2006. The 2006 prop chart supplied to my dealer showed identically pitched props which is why they didn't call it to Sea Ray's attention when the boat was delivered for the PO from the factory. However, their parts catalogue for 2006 showed props with different pitches which agrees with the online prop charts. When I presented this set of facts to Sea Ray their research showed that two different suppliers provided props for 2006 320s, one with both props have 19" pitches (my boat) while the second had 18.5" and 19" pitches as per the online prop chart. Sea Ray engineering test both and the performance was essentially the same so my boat is fine. For the record, my props came from a company in the Philippines.
Alex F
Well-Known Member
- Nov 14, 2006
- 9,166
- Boat Info
- 2005 420DB with AB 11 DLX Tender, Raymarine Electronics (2x12" MFDs) with Vesper AIS
- Engines
- Cummins 450Cs, 9KW Onan Generator, 40HP Yamaha for tender.
Bob,
Thanks for the update and interesting info. Did you have a chance to test your boat with WOT? Does both sides have same RPMs or do you loose 80-100RPMs on one side? My starboard side is consistently lower 80-100RPMs, although still within the specs. I was wandering if having both props at 19" would make operation of both sides the same.
Thanks for the update and interesting info. Did you have a chance to test your boat with WOT? Does both sides have same RPMs or do you loose 80-100RPMs on one side? My starboard side is consistently lower 80-100RPMs, although still within the specs. I was wandering if having both props at 19" would make operation of both sides the same.
Unfortunately I won't be able to put it in the water for another 2 months. But when I do, I intend to run it WOT to see if I get 4800-5200 rpms on each engine. If not, my next call will be to the dealer.
