"Boat has major vibration"

[nymonymgr]

Happy Spring folks....even though the temperature on Long Island doesn't quite say the same thing!!

That said, it's that time once again! My 330DA has been on the hard at MarineMax in Lindenhurst for the winter for some warantee engine work that needed to be done.

The work was completed in November and she's been there ever since, wrapped and waiting for mid April. I was down there on Friday to deliver my radar dome, satelite TV dome and mount so they can reinstall everything. Obviously I had to see her.

I was talking with my service advisor about the "boat has major vibration" notation on the paperwork from last year. He said they run tons of boats so it's something I might not have noticed but they did. Sounds strange, no? I think I would notice a major vibration! Either way when he took my out to the yard to see her we looked at her props. Using a piece of wood to measure we spun both. Port side looks as if two of the blades are just a bit off. No nicks or dents though. Starboard side looks good.

He recommended having them both pulled and reconditioned. She's been running for two seasons without ever coming close to hitting anything.

I did notice, however, that my fuel consumption has deteriorated since she was launched new by about 15% or so.

So my questions are as follows:

1) What might cause a prop to 'change' without actually hitting something?
2) Could a very slight bend of two blades cause a 'major' vibration?
3) What should it cost to have them both done?

Thanks!! :huh:

 

[gregkjones]

Question: Does the boat vibrate only when in forward and/or reverse or does it vibrate in neutral too?

I ask because my boat picked up a vibration last summer but it was at the dock and/or on the go and performance suffered as well. Turned out to be a $50 manifold absolute air pressure sensor, not the MAP sensor BTW, this sensor is different. Once it fails it really kills engine performance and smoothness as it is one of the sensors that dictates fuel delivery, like the MAP. I couldnt believe it when this little sensor turned out to be the problem. I thought the engine had a major problem. BTW, it was only noticeable above idle around 1500RPM and up.

If the problem is only in gear, most here will probably say prop or shaft. It cant be much more than that I think. Alot of people here send their props to propscan to have them tuned. I dont know what it costs but it will surely be more than a simple tune which I think is pretty cheap. I had a prop fixed on a smaller boat for about $100.

 

[nymonymgr]

That's a great question and one I need to get an answer for from the techs at MarineMax. I didn't notice it last time I ran her. My service advisor said I might not have noticed but they run so many boats everyday they pick up on these things pretty quick.

I will pose that question to him. My guess is they will need to run her and get back to me.

 

[Jimmy Buoy]

A "PropScan" dealer will scan the props, provide a detailed (easy to read) printout of their current condition, and give you a firm quote on what they would charge to get them back to spec - FREE OF CHARGE!

 

[Alex F]

SAve your self the trouble. Have the props scanned and tuned to class I. It sounds like you've never done it, so it's way over due for prop scan.

Can the slight bent of 1 prop create the vibration? Sure.
How can the prop get bent if you didn't hit anything? You might have hit something small enough not to notice it, but still bend the prop. Maybe once, maybe several times. It's not always noticable.

It's very possible that props is not the answer to your vibration issue, but you won't know until you get the props back from the shop in 100% working order.

While you at the boat ask your folks to check if the shaft is not bent. It's a simple test by pointing an object to the mid of the shaft's end and spin the prop. The shaft should stay still on the object without wigling up/down.

 

[320Bob]

In addition to what has been about the props have you had your alignment checked? If not have it done once the boat is in the water for a few days after launch.

 

[The Bill Collector]

As they say "flotsam" happens..... Get 'em pulled and checked while it's sitting on the hard. My wheels run about $400 a piece for a scan and repair.... As posted previously, no repair, no charge !!

 

[Luckydogs]

I was having a vibration (not major) in my port motor, changed the plugs and all is good now

 

[nymonymgr]

Thanks for all the insight everyone!

Got an email from my service writer this morning. Once the commission the tech will bay test and pin point the vibration so we can get it addressed. I'll let you know what it is when I find out.