aneely
New Member
I will investigate that as soon as I'm able to run it up to WOT. Prop is 14.5d 19p 4 blade so I'm fairly sure that isn't too high but I will double check for WOT rpm which I believe for my 230da 5.7L Mercruiser is 4200 - 4600
Coupler Failure
- Thread starter aneely
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- coupler questions
I will investigate that as soon as I'm able to run it up to WOT. Prop is 14.5d 19p 4 blade so I'm fairly sure that isn't too high but I will double check for WOT rpm which I believe for my 230da 5.7L Mercruiser is 4200 - 4600
aneely
New Member
So I just wanted to update everyone after my sea test today and turns out I've got a lot to learn about my boat. Coupler seems fine so I believe I was just ventilating or cavitating (have to go back and read cliff's post LOL). I did discover my trim gauge is way off the mark so I was running out in the swells with my trim over half way up. I'm also wondering what kind of prop is best for running in swells? Would a larger diameter three blade do better than the smaller 4 blade? I did a WOT run today since she was running great and was only getting the very low range 4300rpm about 35mph out of her with the 14.5d 19p 4 blade prop so I'm thinking about getting a 15.5d 17p 3 blade...any opinions?
Cliff gave you ventilation (what you experienced), I gave cavitation. Either way, no harm no foul and it's good to hear that it sounds like nothing is wrong.
Trim gauge... On the starboard side of your drive (look where it pivots up/down) is a black, plastic hockey puck looking thing. It will say "sender" on it. That tells your gauge what to show. With your key turned to the ON position, and the drive trimmed all the way down, have someone rotate that hockey puck until the gauge shows what you want it to show. Don't touch the hockey on the other side.
If the conditions weren't great, it won't be a good enough test to tell WOT. And maybe you can still trim up some more than what you did? Basically, trim up till speed either no longer increases or it starts to ventilate (then back down a click or two).
On Sea Ray's website, under Owner's Resources, is a prop matrix. It lists boats with the various engine combos and what prop they would of came with as standard equip. Check that and be 100% sure of WOT before doing anything.
Is the bottom super clean?
Trim gauge... On the starboard side of your drive (look where it pivots up/down) is a black, plastic hockey puck looking thing. It will say "sender" on it. That tells your gauge what to show. With your key turned to the ON position, and the drive trimmed all the way down, have someone rotate that hockey puck until the gauge shows what you want it to show. Don't touch the hockey on the other side.
If the conditions weren't great, it won't be a good enough test to tell WOT. And maybe you can still trim up some more than what you did? Basically, trim up till speed either no longer increases or it starts to ventilate (then back down a click or two).
On Sea Ray's website, under Owner's Resources, is a prop matrix. It lists boats with the various engine combos and what prop they would of came with as standard equip. Check that and be 100% sure of WOT before doing anything.
Is the bottom super clean?
The Mercruiser 5.7/260HP WOT RPM recommendation is 4200-4600. At 4300 I would say you are where you are supposed to be. At 4300 lbs. listed dry weight your boat is on the heavy side for that power combination. Add about 250 lbs. for fuel, 80 lbs. for water and whatever you and your crew weighs you are pushing close to 5000 lbs. That's a lot for 260 ponies.
If you want to try experimenting with props I would find a local prop shop and give them the figures on your boat. (Length, beam and weight. Be sure and tell him 5000 lbs. not 4300) But remember, you will be sacrificing something to gain something else. In other words, you could change to a prop to reduce cavitation but reduce top speed. I've owned several boats that size and power combination and I would be surprised if you have a cavitation "problem." I think you just had the boat "out of trim."
I have a trim gauge on my Cobalt and never use it. As you get to know your boat you should be able to "feel" when the boat is trimmed properly. Start with the drive all the way down, or in, and make small adjustments up. Tthe bow will come up; the boat will feel looser. Look at where the bow wave comes off the boat. It will begin to move aft. Watch your speed and RPMs and notice the relationship. Do you have trim tabs? Their position will make a difference as well. And do your speed and RPM test in Mission Bay or someplace where it's fairly calm.
The last thing you want to do is start making a lot of wild changes. Your boat is heavy and somewhat underpowered. There is not a lot you can do. You boat in a beautiful part of the country. Just realize you are going to cruise at 25-30 MPH and enjoy the scenery.
Shawn
If you want to try experimenting with props I would find a local prop shop and give them the figures on your boat. (Length, beam and weight. Be sure and tell him 5000 lbs. not 4300) But remember, you will be sacrificing something to gain something else. In other words, you could change to a prop to reduce cavitation but reduce top speed. I've owned several boats that size and power combination and I would be surprised if you have a cavitation "problem." I think you just had the boat "out of trim."
I have a trim gauge on my Cobalt and never use it. As you get to know your boat you should be able to "feel" when the boat is trimmed properly. Start with the drive all the way down, or in, and make small adjustments up. Tthe bow will come up; the boat will feel looser. Look at where the bow wave comes off the boat. It will begin to move aft. Watch your speed and RPMs and notice the relationship. Do you have trim tabs? Their position will make a difference as well. And do your speed and RPM test in Mission Bay or someplace where it's fairly calm.
The last thing you want to do is start making a lot of wild changes. Your boat is heavy and somewhat underpowered. There is not a lot you can do. You boat in a beautiful part of the country. Just realize you are going to cruise at 25-30 MPH and enjoy the scenery.
Shawn
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At work... finished shovelling... not too many people stopping by the store today... kinda bored. :smt001
According to my dealer handbook from '94, the stock prop would have been 14.5x17. Coupled to a 1.5 ratio drive, that would give a top speed in the low 40's at 4600RPM.
Shawn, I hear what you're saying about 'more power is never bad', but his boat actually performs VERY well with that 350. I've been on that model with a V6 many times (my brother used to have one) and with a 350. It does surprisingly well with the V6 and we were even able to ski with it (could get up on one ski, though). With the 350, it almost feels like too much engine... well, nah, you can never have TOO MUCH! Point is, it's absolutely not underpowered - don't scare him! :smt001
According to my dealer handbook from '94, the stock prop would have been 14.5x17. Coupled to a 1.5 ratio drive, that would give a top speed in the low 40's at 4600RPM.
Shawn, I hear what you're saying about 'more power is never bad', but his boat actually performs VERY well with that 350. I've been on that model with a V6 many times (my brother used to have one) and with a 350. It does surprisingly well with the V6 and we were even able to ski with it (could get up on one ski, though). With the 350, it almost feels like too much engine... well, nah, you can never have TOO MUCH! Point is, it's absolutely not underpowered - don't scare him! :smt001
Point taken Dennis. The point I want to make is for him to not start making a lot of changes that will be needless and costly. It would be better for him to use what he has and get to know the boat better. No offense at all intended towards Andy but because of his lack of knowledge for his boat and how it runs we spent a 4 1/2 page thread on a bad coupler when it was really "operator error." And Andy, that's OK. This is how you learn these things. I bet moving forward you will be more aware of how your boat feels, sounds and handles.
Enjoy!
Enjoy!
I couldn't agree with you more. Get used to the boat before even CONSIDERING any changes.
aneely
New Member
Thanks all and no worries about offending me Shawn, I have thick skin and I'm hoping this thread may be useful to another inexperience boater who may experience a similar issue in the future. The bottom of the boat is a bit rough with hard water stains. I believe the previous owners left it in lake mead for extended periods of time. I'm working to clean the hard water off the bottom but it's slow going, wears out my arm scrubbing. I'm thinking having a spare prop on board would be a good thing. Definitely not looking to just throw money away which is why I'm seeking advice for the second prop, what's best for offshore use in 2-4ft swells. That is typically what we see here in San Diego. As for my WOT run it was done in Mission Bay on calm water and I did two runs in opposite directions just to check on any resistance from wind, current, etc... and got the same results both directions. I'm not looking for a speed boat with my cruiser just good performance. I'd never run it out that hard in the open ocean, just feel that would be dangerous and irresponsible to hit swells that fast in a 23ft boat. I'm happy with the power that 5.7L 260 horse is giving me, it will be more than enough for pulling a skier around the bay in the summer and running out the the fishing ground every now and then looking for the tuna. After speaking with the salesman at the dealership in Vegas where I bought it I'm leaning toward keeping the prop diameter under 15, something around what I have at 14.5 or maybe a touch bigger 14.75 and just going down to a 17 pitch 3 blade from the 19 pitch 4 blade I have.
Andy
Andy
CliffA
Well-Known Member
- Dec 29, 2009
- 4,712
- Boat Info
- 2001 Sea Ray 340DA
Name: 'Happy Place'
4.5kW West. Generator
Purchased Nov. 2014
Fresh Water Use
- Engines
- Twin Merc. 6.2L (MPI)
640 hp (Total)
Raw Water Cooled
V-Drive Transmissions
if the hull stains came from prolonged exposure to lake water they are easily removed with oxalic acid...many products contain oxalic acid such as many of the hull cleaners sold at stores like West Marine...some toilet bowl cleaners also contain oxalic acid...it is also a great rust remover....just spray the liquid with the acid on the hull and sit back and watch with amazement....the stain will dissolve off the hull before your eyes...then just rinse with fresh water and you are done....for really tough stains you may have to repeat and use a brush, but usually no hard scrubbing is needed....the acid will not harm the gelcoat....
cliff
aneely
New Member
CliffA
Well-Known Member
- Dec 29, 2009
- 4,712
- Boat Info
- 2001 Sea Ray 340DA
Name: 'Happy Place'
4.5kW West. Generator
Purchased Nov. 2014
Fresh Water Use
- Engines
- Twin Merc. 6.2L (MPI)
640 hp (Total)
Raw Water Cooled
V-Drive Transmissions
sounds like the original prop was a 14.5" x 17P 3 blade....i believe the OP said he is running a 14.5" x 19P 4 blade prop....if that is accurate i think he has too much prop and the engine cannot spin it up properly....usually when you go from a 3 blade prop to a 4 blade prop you want to go 'DOWN' in pitch by 1 or 2 due to the increase in the blade surface from the 4th blade....in this case the 4 blade prop is 'UP' by 2 pitch compared to the 3 blade prop....
this may be a contributing factor why the first coupler failed....
cliff
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