Repowering a Zodiac Medline III

[shahid]

Dear All

I intend to repower my Zodiac Medline III (7.3 m LOA) Rib with a 200 HP Suzuki 4 Stroke Inline 4.

The boat currently is fitted with twin Yamaha F115 motors (Long Shaft)

The shift to single is mainly on account of the fact that the boat is on a swinging mooring and the twins sit really low in the water (especially after a retube a few years ago). Being in a high corrosion tropical environment, it is murder on the trim units! Im hoping the reduction weight of about 130 Kgs. will be sufficient to raise the transom by enough to make a difference.

Plus maintaining two old engines in this environment was really expensive!

I would very much appreciate all of your inputs on the following:

1. Propeller Size for the 200 Hp inline 4. The Boat weighs in at 1400 Kgs. plus engine. Would like to have good efficiency and top end speed rather than brute acceleration. Looking at 3 blade 151/4" dia x 19 Pitch vs 16 Dia X 18.5 Pitch.

2. Will an XL Shaft Length be ok for a single engine configuration on this RIB?

Thanks in advance

Shahid

[office888]

Originally Posted by shahid

Dear All

I intend to repower my Zodiac Medline III (7.3 m LOA) Rib with a 200 HP Suzuki 4 Stroke Inline 4.

The boat currently is fitted with twin Yamaha F115 motors (Long Shaft)

The shift to single is mainly on account of the fact that the boat is on a swinging mooring and the twins sit really low in the water (especially after a retube a few years ago). Being in a high corrosion tropical environment, it is murder on the trim units! Im hoping the reduction weight of about 130 Kgs. will be sufficient to raise the transom by enough to make a difference.

Plus maintaining two old engines in this environment was really expensive!

I would very much appreciate all of your inputs on the following:

1. Propeller Size for the 200 Hp inline 4. The Boat weighs in at 1400 Kgs. plus engine. Would like to have good efficiency and top end speed rather than brute acceleration. Looking at 3 blade 151/4" dia x 19 Pitch vs 16 Dia X 18.5 Pitch.

2. Will an XL Shaft Length be ok for a single engine configuration on this RIB?

Thanks in advance

Shahid

I sent you a private message.

[totallydave]

rule of thumb is 1 inch of diameter is equal to 1 1/2 to 2 inches of pitch.

[shahid]

Originally Posted by totallydave

rule of thumb is 1 inch of diameter is equal to 1 1/2 to 2 inches of pitch.

Thanks Dave!

Any recommendations for ideal prop size for my application?

[shahid]

Originally Posted by office888

I sent you a private message.

Hi Richard,

Thanks. I sent you a reply with my email, can you confirm receipt?

Best
Shahid

[office888]

Originally Posted by shahid

Hi Richard,

Thanks. I sent you a reply with my email, can you confirm receipt?

Best
Shahid

Got it! I'll send you an email this morning.

PS: With a single engine, the boat requires an XL (25") shaft engine.