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Old 17 August 2014, 15:06   #21
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What Pikey said Jason the ladder will be causing some drag.

Whats the weather like in Malta at the moment Jason ?
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Old 17 August 2014, 15:49   #22
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What Pikey said Jason the ladder will be causing some drag.

Whats the weather like in Malta at the moment Jason ?
I will remove the ladder and try without. the weather isn't so good this summer we are having a lot of wind and rough sea that makes you feel sick sometimes.
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Old 17 August 2014, 16:09   #23
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I will remove the ladder and try without. the weather isn't so good this summer we are having a lot of wind and rough sea that makes you feel sick sometimes.
At least you have got plenty sheltered places to go boating and fishing inside the harbour walls
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Old 17 August 2014, 18:47   #24
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I agree with the rest. Mount the ladder higher up, so it is well clear of the water while under way. I, too, think that's the source of your problem.

Just an observation. I see your propeller is black. Both the Honda propellers I had were the same colour as the engine and stamped Honda. Is yours a Honda prop?
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Old 18 August 2014, 08:57   #25
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I agree with the rest. Mount the ladder higher up, so it is well clear of the water while under way. I, too, think that's the source of your problem.

Just an observation. I see your propeller is black. Both the Honda propellers I had were the same colour as the engine and stamped Honda. Is yours a Honda prop?
yes I will try it without the ladder. and yes the prop was with the engine from the agent but the prop was packed and labelled Honda marina solas
which I believe it is made from Solas for Honda
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Old 19 August 2014, 09:46   #26
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hi all I went to do some modification to the ladder and I gave a good look to the transom and noticed that the ladder is above of the hull and the cav plate. now I am confused if the ladder is causing the problem of ventilated prop. I know that when I am on plane the ladder hits the water as it splashes a lot of water. I have take the part no on the prop can some one tell me what is the brand of it by the part no?

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Old 19 August 2014, 10:47   #27
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Jason,

if you turn the prop so one of the blades is top - what is the clearance (space) between the blade tip and the bottom of the cav plate? YOu might be suffering from the same problem as I did when I bought my boat.

It might be an illusion from the angle of your picture, but I had a similar thing to what you describe on a Yam 55 which came with my boat. - Yam sold a prop called a a "speed" prop - it had reduced diameter for less prop drag, so the engine's power could go to spinning a higher pitch to push the boat along faster.

That theory worked fine with a light weight flat bottom "skimming" hull, but I had this on the back of a 5m 1/2 ton rib!

The prop didnlt have enough blade area to "grip" the water, so it let go like you describe when I opened the throttle too far. It also let go at every third wave, if I turned too quickly...


What number is stamped on the prop? Normally that will give a clue to diameter as well as pitch.

I had a similar (bit not so spectacular) problem when I put the Merc on the transom. it had a 10.5" dia prop - 14" pitch. Over revved nicely (and let go if I pushed it hard in big waves.) replaced with another 14" pitch but 11" dia. It now never lets go, and the engine feels like it's connected "solidly" to the water.

All of that because the engines were on ligher / less drag inducing boats before I got them.
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Old 19 August 2014, 13:22   #28
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Either way that ladder is just wrong as it shouldn't extend anywhere near the bottom of the hull. Take it off and go for a boat ride. Then you will know!

The other option is to take a clear video of the ladder/motor at speed and see if there is something noticeable. The ladder doesn't look exactly easy to remove.
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Old 24 August 2014, 08:52   #29
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ID:	98228 I have take a picture so you can see the distance of the prop.

if you turn the prop so one of the blades is top - what is the clearance (space) between the blade tip and the bottom of the cav plate? YOu might be suffering from the same problem as I did when I bought my boat.

It might be an illusion from the angle of your picture, but I had a similar thing to what you describe on a Yam 55 which came with my boat. - Yam sold a prop called a a "speed" prop - it had reduced diameter for less prop drag, so the engine's power could go to spinning a higher pitch to push the boat along faster.

That theory worked fine with a light weight flat bottom "skimming" hull, but I had this on the back of a 5m 1/2 ton rib!

The prop didnlt have enough blade area to "grip" the water, so it let go like you describe when I opened the throttle too far. It also let go at every third wave, if I turned too quickly...


What number is stamped on the prop? Normally that will give a clue to diameter as well as pitch.

I had a similar (bit not so spectacular) problem when I put the Merc on the transom. it had a 10.5" dia prop - 14" pitch. Over revved nicely (and let go if I pushed it hard in big waves.) replaced with another 14" pitch but 11" dia. It now never lets go, and the engine feels like it's connected "solidly" to the water.

All of that because the engines were on ligher / less drag inducing boats before I got them.[/QUOTE]
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Old 25 August 2014, 08:28   #30
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Jason,

That is perceptively the same sort of gap I had on both the Merc & the Yam when I got them. I reckon you could go up a bit in diameter and probably solve the "letting go" problems.

Just remember that bigger diametrer = a bit more drag, so you may need to go down in pitch as well, but if it solves the grip issue you can play with the pitch afterwards - the effect of altering pitch can be estimated fairly well - diamter is a "try it and see" job.
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