GatorBob

Help!!! Major Cavitation Issues

13 posts in this topic

I have a 2011 Bennington 2275GCW with 150 HP Yamaha and elliptical pontoons.

I have had cavitation issues with this boat since the day I bought it 6 years ago.  Have had 3 different props on it, no change.

Cavitation is worst with 5 or more people on the boat and if the water is at all choppy.  I have used all combinations of trim and seating configuration (moving bodies around in boat).  Nothing works.  Dealer gave up on it after 3rd prop (I paid for all 3!!!) and could never replicate the problem because they only had 1 or 2 bodies on board.  

I don't understand why, but it occasionally occurs on our outward part of the trip but occurs almost 100% of the time after being out for hours (low speed) and then powering up on the return trip.  While the boat will go 38 mph top speed, it will start to cavitate on anything over 10 mph or even less - 7 mph.  Thus if I go out 20 miles, it takes me over 3-4 hours to return.  This is extremely frustrating and very embarrassing with passengers on board.

I am at wits end on what to do.  I only take the boat out 2-3 times a year because of this issue.  In my 6 years of owning this boat, I have never had a day on the lake or gulf of mexico with 4 or more passengers when this did not happen.

 

Share this post


Link to post
Share on other sites

Check your mounting holes, motor might be too high. I had some issues with cavitation and lowered the motor 1 hole, seems to be much better.

2 people like this

Share this post


Link to post
Share on other sites

Weird. This is the first I've heard of this issue on an elliptical. Check motor height. Do you have a 20" shaft? 

1 person likes this

Share this post


Link to post
Share on other sites

Motor height or shaft length is definitely your issue, probably exacerbated by having multiple people in front of the centerline of the boat thus making it worse. Possiblely big cooler placement, live wells being filled etc. too. I'd start with the obvious and easiest and go from there. 

2 people like this

Share this post


Link to post
Share on other sites

A 4 blade prop may help as well.  :Like:

Share this post


Link to post
Share on other sites

The motor is already down as far as it will go.

No coolers or bait wells in back. 

I have moved people all around including all in back of boat.

Nothing works.  Extremely frustrating!!!

Share this post


Link to post
Share on other sites

Could the prop be to low?

Share this post


Link to post
Share on other sites
On ‎8‎/‎4‎/‎2017 at 5:47 PM, GatorBob said:

I have a 2011 Bennington 2275GCW with 150 HP Yamaha and elliptical pontoons.

I have had cavitation issues with this boat since the day I bought it 6 years ago.  Have had 3 different props on it, no change.

Cavitation is worst with 5 or more people on the boat and if the water is at all choppy.  I have used all combinations of trim and seating configuration (moving bodies around in boat).  Nothing works.  Dealer gave up on it after 3rd prop (I paid for all 3!!!) and could never replicate the problem because they only had 1 or 2 bodies on board.  

I don't understand why, but it occasionally occurs on our outward part of the trip but occurs almost 100% of the time after being out for hours (low speed) and then powering up on the return trip.  While the boat will go 38 mph top speed, it will start to cavitate on anything over 10 mph or even less - 7 mph.  Thus if I go out 20 miles, it takes me over 3-4 hours to return.  This is extremely frustrating and very embarrassing with passengers on board.

I am at wits end on what to do.  I only take the boat out 2-3 times a year because of this issue.  In my 6 years of owning this boat, I have never had a day on the lake or gulf of mexico with 4 or more passengers when this did not happen.

 

Have any video of this gatorbob? There are two elliptical bennington's on our lake, one has the 115HO and the other is a GCW with a 150. They both get on it all the time with no issues.

Is your trim not dialed in in the back? There is an adjustment that could be limiting how far the motor is trimming down. Could be that the dealer never adjusted this. So it shows all the way down but isn't. Make sense?

Share this post


Link to post
Share on other sites

Going to throw a stupid thought in here.... does it have the wrong length shaft on the motor?? Maybe a 20" shaft instead of a 25"? Kind of make sense since this is been going on since new. 

1 person likes this

Share this post


Link to post
Share on other sites

Really sounds like you may have a 20" shaft motor on your boat. You stated the motor is all the way down,but no mention of the motor shaft length. Damn you adk,you beat me to the punch by 4 mins.

2 people like this

Share this post


Link to post
Share on other sites

Just checked the boat builder and the ellipticals call for a 20" shaft, need to double check the trim adjustments and make sure that it's dropping all the way down, and check the bushing in the prop, maybe it's just spinning around the bushing and it's not actually cavitating? 

Share this post


Link to post
Share on other sites
1 minute ago, 1Blderbob said:

Really sounds like you may have a 20" shaft motor on your boat. You stated the motor is all the way down,but no mention of the motor shaft length. Damn you adk,you beat me to the punch by 4 mins.

All I can say is my patience wouldn't last that long, I'd of got rid of the boat by now!! 

Share this post


Link to post
Share on other sites

Is exhaust gas somehow getting out of the engine in front of, or around, the prop instead of going through it?

That's the only thing that comes to mind after hearing all the comments above...

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now

  • Forum Statistics

    • Total Topics
      7,197
    • Total Posts
      101,875