Almost finished my building my RIB but..

[Ashley Lacey]

Hi all

I have been veiwing this site for some time now and I must admit you all have a great love for your boats and the hole RIB experiance.

Thanks to all for your veiws and opinions as I have found them very useful.

I'm looking forward to next few weeks as I hope to finish building my RIB and then get her in the water. I just need to fit the tubes and set up the engine.

The last job, fitting the engine, does bother me as from reading all I can it appears it can make or break all the hard work I have done.
I can't find anthing specific on fitting a ETEC 250 (21 pitch prop) to a 7+ metre Crompton/Ballistic hull. Can anyone help?

I have been advised 1.5 inches to starboard and 1.5 inches up from cav plate is a good place to start!!!

Thank you

Ash

Will post build pics soon if anyone is interested.

[RIB BOI]

I dont no about the fitting of the motor. but yes plz do post pic's of the build

Thanks

RIB BOI

[Seaharrier]

Ash,

Keep an eye on the rev’s during the first runs. We have the same engine and my guess it that you will need an other prop with a bigger pitch. We tested 6 different props on our rib(7.4m). With the standard prop (21 pitch) we easily reached the 6000 RMP limit. You could see the engine vibrate a little due to the interrupter. For us the best size was one with a 23 pitch.

As you can see on the attached picture, ours was mounted about 1.5 inches to starboard and for us that works very well.

Paul

[Ashley Lacey]

Hi All

Thanks for the info Paul.

I've had the engine delivered today and the dealer said to fit the motor bang in the middle and the cav plate one inch up from the bottom of the "v".

He advised that the only reason for mounting to starbourd was from the old powerboating days when they used to run big power high up with surface piercing props.

I new this wouldn't be an easy decision to make!

Looks like I will have to make up my mind by Tuesday as that is when the flowcoat with be set hard and the engine can go on.

Thanks

Ash

[Seaharrier]

Ash,

What shaft did you take? And did you ask your dealer about the right pitch?
Good luck with your project and post some pic’s when she’s ready!

Paul

[Ashley Lacey]

Hi Paul

Sorry for the late reply, been down the boat.

The engine is the 250 hp Etec with 25 inch shaft and the stanfard 21 pitch prop. I will have a 23 to try. (I hope!).

I will post some pics to the end of next week when I should have some time.

All ther best

Ash

[Ashley Lacey]

Hi all

I have finished building my RIB and she was lauched last Saturday.

She is going great. It is so much fun.

Seaharrier (Paul), I will post a few pics as soon as I load the them onto the computer and work out how to post them.

Paul, I gave her a quick blast (motor has only done around 2 hours) up to 5500 rpm which was about 53/55 mph then the wife started to complain!
I hope to try a full speed run tonight with the wife safely on dry land land.

For your info I am running a Viper 23 with the motor mounted in the centre. She does appear to dip slighty to port at low revs but that may be the pull of the tide. I will have to do more RIB time to confirm this because at 35mph she appears to level out perfectly.

Anyway, I am going to Herm Island tonight (which is about 3 miles away) for dinner. The tides are good and it is lovey there. Any of you been there on your trips across the Channel?

All the best.

Ashley