Humber Ocean Pro 6.3 Prop choice?

[Gav03830]

I've just purchased an Ocean Pro 6.3 with DF140 on the back.

Despite a couple of niggles I love the boat already.

I've done a few hours now in varying conditions. Max speed is approx 31-32kts at 5100-5300rpm. Prop on the back is 14x23, clearly too big given the low max revs.

I spoke to a lady at Humber today and she said I should use a 21. I've read on here that 19 is also used.

Just wondering what others prefer. I'm not looking for lighting acceleration but would like a decent cruise in the high 20 knots. Generally going to be and my two kids on board, exploring the west coast of Scotland and out to Isle of May for the odd fishing trip.

What max/cruise speed people are getting.

Thanks

Gav

[xpertski]

I used to have that exact same setup, had a 21” prop and was getting about 33/34 knots. I think 21” is the best balance

[Gav03830]

Originally Posted by xpertski

I used to have that exact same setup, had a 21” prop and was getting about 33/34 knots. I think 21” is the best balance

Thanks for that. I think 21 was the standard size so not sure why it's got a 23, unless it's been taking heavy loads?

[xpertski]

Originally Posted by Gav03830

Thanks for that. I think 21 was the standard size so not sure why it's got a 23, unless it's been taking heavy loads?

Yes possibly, it’ll be fine with that prop but I think as you say 21” is standard. Lovely boat, enjoy it!

[stepheneyre]

i have a humber destroyer 7 mts with the new 200hp mercury ( new 2019)
i have a 4 bladed S/s prop 25" pitch think you should try the 21"Pitch
i have 1 for sale if you interested ( need to check if will fit)
call me
thanks
Stephen 07813207944

[Gav03830]

Originally Posted by stepheneyre

i have a humber destroyer 7 mts with the new 200hp mercury ( new 2019)
i have a 4 bladed S/s prop 25" pitch think you should try the 21"Pitch
i have 1 for sale if you interested ( need to check if will fit)
call me
thanks
Stephen 07813207944

Thanks Stephen, I've got a 21 arriving in the post today.

[Gav03830]

So we finally managed to get out with the new prop (21") yesterday . Managed to get 33-34 kts at about 5800-5900 rpm. Have read quite a few people managing 38-39 kts with same engine. We had about 90l of fuel and weight of two adults. Cruise was about 26kts at 5000rpm.

Thought I might be able to cruise at that speed at lower rpm. Should I try a 19" prop or be happy cruising at 5000-5100?

Apart from that I'm delighted with the boat and looking forward to a few weeks on the west coast later this month.