I have an Arimar 430 Rib (later became a valiant 430 I believe), that I bought mainly for the engine 2003 mercury 40Hp EFI 3cyl - buy an engine get a rib free - type of deal - yes it was a late night ebay purchase
The engine is good (now the fuel system is cleaned out and the cracked battery terminal is replaced) and I figured fairly often hulls come up minus an engine but while it holds air I am getting some use out of it. (It doesn't look to bad from a distance!
In the past someone has added a (nasty) central console and moved the steering forward so its console butts up against the front seat. This seems to work quite well for single handed use. the original 'manufacturer' steering console position and seat put all the weight at the back. Given that at some trim angles / speeds it can throw water over the transom I am glad to be sat further forward.
The 40 was the biggest engine option recommended when the rib was new.
The Rib is ok and I am slowly improving it and my mind has turned to the prop. It currently has a fairly abused Michigan vortex 992406 which apparently by looking up the part number is 10 3/8" dia 13" Pitch (3 blade).
My thinking was to replace that with a new one and then evaluate it. However doing a bit of research, this diameter / pitch seems a little small for a 40HP on a 4.3m rib.
The solas prop selector for 40Hp 4 stroke mercury are all larger dia with a range of pitches either side.
Messing with the mercury prop selector, it has higher pitch for props of that diameter.
Playing with the michigan wheel prop selector I couldn't make it select my prop for my engine
The previous owner of my boat used it for fishing and freely admitted he didn't know much about boats and was a bit scared of it - he replaced it with a little SIB.
I don't know if he fitted the current prop or the owner before him, I suspect it was him that bounced it off the bottom though.I gave it a clean up with a file and straightened out a small ding but it is not an ideal candidate for testing.
Last summer flat out I had about 23knots on the GPS and if anything it seems to want to over rev, I have to be fairly careful to avoid the rev limiter.
That was 1/2 tank fuel me 90Kgs and my daughter about 40kgs on board.
I don't really know if that is good or bad!
Is anyone running a similar sized rib with a mercury/mariner 40hp 3 cylinder four stroke? If so care to share prop size.
If not shall I just go with my original plan and start by putting a new one as fitted previously.
(use is to be general blatting about in reasonable weather - maybe pull a ringo with the kids in Christchurch bay and the odd trip round to Poole or the Solent.
Thanks for reading and for any advice!