2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

[Bblakewv]

I have a brand new 2011 Bentley 200 cruise with a 60bigfoot at wot only turn 4200 Rpm's. 15mph
I've read that max power range From 5500 to 6000...... I'm very new to boating so not sure
Where I should start !! Do I need to move the motor higher or lower ??? have noticed at wot water splashes
Up on rear of the deck like a big wave. I trim up n down doesn't help speed or Rpm's
Or do I need a diff prop ? Dealership says throttle is opening all the way

Thanks for ur time and any help

 

[Silvertip]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

Look at the prop for the Merc part number. The last numbers will be the pitch. That combination should probably have a 14 x 9 pontoon prop and I'm betting it has one with a lot more pitch.

 

[WaterDR]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

You just have the wrong prop.

 

[Old Screwball]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

Ditto the prop pitch. I was experimenting and put a 13.5 X 17 on my new 18' Party Barge. Only got 4300 rpm. With the stock 13 pitch I would over speed. I've got a new 15 pitch that should do the job. Going back to the river first of August'

Funny though, if you just bought it, did you change the prop?? Usually the dealer kinda knows what they are doing and don't blow the prop size.

Good Luck

 

[WaterDR]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

My dealer water tested mine and provided me witht he results. Strange that it would be that far off.

 

[Silvertip]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

There are dealers that really want to do the job right to ensure you are happy. Then there are dealers that just want your money and once it is in hand they push you out the door with whatever it is they cobbled together. Keep in mind that outboard above about 40 HP don't come from the manufacturer with a prop because they have no idea what "type" of vessel the engine may be installed on. It is the dealers responsibility to make that call. Some do it right, some take a crack at it, and some simply don't care and let the owner fumble through the process (if they even know what the problem is), A wrong prop can prematurely kill an engine from lugging (too much pitch) to over reving (too little pitch). Fuel economy is also impacted by incorrect prop selection.

 

[Bblakewv]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

Thanks for all the reply's I have the boat dock at the lake. I'm going to get by there and check to see what prop I have .... Maybe then y'all. Can point me in the right direction.
Thanks again

 

[lakegeorge]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

If it's not running right take it to the dealer, that's what they are there for.

 

[Bblakewv]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

Well the dealership says that it's fine and normal but I disagree.....
Anyways. Prop. Says 13.75X13
I have no clue which number is the pitch or what the number is so..........Thanks for any and all help

 

[WaterDR]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

The first number is the size the second is the pitch.

It is real simple, the prop you use should allow the motor to hit max desired rpms. If you are not doing that, you have the wrong prop. Your rpms are WAY too low for WOT. You will damage the motor.

Stop into a different marine shop and get a second opinion.

 

[WaterDR]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

BTW, are you under heavy load?

 

[Bblakewv]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

That is with two adults and a two year old. So I'd say not a heavy load

 

[MH Hawker]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

I would have a word with the dealer ship. First asking why its not turning the right RPM`s. You need a 11 or a 9 pitch.

 

[Bblakewv]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

Any one else running my Similar setup and rig ?!?!?

 

[Silvertip]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

Big Foot lower units run a 2.33 gear set so a 14 x 9 or 14 x 11 pontoon prop is in order. Pontoon props have big rounded ears and provide more push in both forward and reverse than standard props. Workboats and pontoons need a much different prop than a V-hull. But before spending money on props, make sure the throttle is opening all the way. Make sure the engine is not down a cylinder (you'd not be the first person to not know what that feels like). If the engine is not running right or making full power any new prop will not solve the problem.

 

[Bblakewv]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

The motor is mounted as low as possible also does that have something to do with the water coming up around motor and even splashing up on rear deck. Thanks for the info

 

[WaterDR]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

I have never seen a motor soak the rear of a pontoon. Lowering a motor will lower speed a little, but not sure if it will change the rpms that much. The prop is already submerged. I can put mine as far down in the water as I can and the rpms don't budge. It I trim it up too high and it starts to come out of the water, they will increase.

You are 100% correct IMO to think that something is not right. Not sure if anyone really knows what it is.

With the motor trimmed fully down, one person on the boat, and at WOT, a properly operating motor with a correct prop should hit the high-side of the rpm range.

If this were my boat, and I had no other indication that the motor was jacked, I would swap the prop. I would have already stopped at another marina and asked for another opinion. I would have looked online for the same set-up and see what props folks are running for comparison.

A quick call to Bentley might help too.

 

[craigmack]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

Do you have water in the toons? I just had a leak repaired and gained 600 or so RPMs Once it began listing to one side it was easy to tell what the problem was Can you post pics of your boat and how it sits in the water?

 

[Silvertip]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

This is very simple math. For each inch of pitch change (up or down) rpm changes by about 200 rpm. A 14 x 9 vs a 13-3/4 (ignore the diameter change as it is not a factor here), means there is a 4 inch difference in pitch. 4 x 200 = 800 rpm. Install the correct prop. The engine will likely pick up additional rpm and be in the 5500 - 6000 range because it will be operating in the more favorable portion of its HP band..

 

[Bblakewv]

Re: 2011 Bentley 200 cruise 60bigfoot. Rpm's ??????

No water in toons it sit perfect in the water just lack of wot rpm's...
How do u know if ur motor is sittin too low ? I think I've read that my water coming up on rear of the deck it caused by motor being too low