Water-skiing

[Charles]

We had a debate in another thread, Diesel vs petrol Outboards.
My question is , has anyone had much experience with diesel inboards and water-skiing? They produce a lot of torque, but are they good enough to pull a mono-skiier, possibly two, out of the water rapidly? I would appreciate peoples comments based on their experience.
This is a pretty 'loaded' question based on different scenarios.... take an 8.1m standard type rib, ton and a half, with a bit of fuel, couple of people, anyone have or had this set-up? Clearly the prop is a mitigating factor.
A good example would be 'Blue Ice'

[tsunami]

I've had quite a lot of experience with diesel ribs of around 7m up although I've never tried waterski-ing behind one. With the diesel engine there is definitely a very sluggish response to the throttle initially but once the turbo kicks in the acceleration can be quite amazing.
I think it would depend a lot on the size of the person trying to ski. I think personally I would have a lot of problems trying to ski behind a diesel boat as I'm around the 15.5 stone mark and like a lot of immediate throttle to pull me out!! With the diesel the slow pull on the arms for the first couple of seconds might be too much for the heaver person!
However I do think the diesel boat would make the idea wakeboarding boat as you don't need much initial power or speed to get up out of the water and the wake put up by the extra weight of the boat would be great.
If you do a lot of skiing from your boat you might be better staying with the petrol outboard!

[Scubakid]

Having skied behind a diesel boat it is far more difficult as the startup is much slower until the turbo cuts in. The tow with a petrol boat was much easer but you have to count the cost of the fuel a day out behind a petrol boat if very expensive.

John

[Alan]

where petrol is free! Ok, well not free maybe but a damn sight cheaper than for the rest of us on the mainland.

My 2 cents would be outboard everytime vs inboard derv. Blistering acceleration on the modern fuel injected units...optimax, hpdi etc etc.

I have some experience of Blue Ice ... although not waterskiing ... as I have cruised with John Lancaster the owner. She is pretty quick onto the plane, certainly far quicker than say Cyanide (9.5 Scorpion, 300hp diesel) which is my only experience of diesel. As you say stealth, prop selection will be important. A smaller pitch prop might give you the "holeshot" for skiing but will reduce your top end speed. This might be a sacrifice worth making particularly if you run the boat loaded most of the time and need a smaller pitch to maintain WOT.

Of course your other option in the Channel Islands would be inboard petrol 7.5 Rib with 315hp 5.7l fuel injected V8 would do very nicely!

HTH Alan

[Charles]

It is a difficult decision ..... weighing up the different options. We do a LOT of waterskiing, as well as a lot of family cruising. We would like to expand our horizons, go further south, but petrol is not always as readily available as diesel is. You are right though, Alan, price is not a deciding factor , in fact diesel is almost just as much as petrol over here. I think I will have to go for a Mariner Optimax, Evinrude is out, Mercury seems to have bitten the dust, sheesh, not many options left. Your suggestion is good except the RIB will be in excess of 8 Metres-not big enough!(the inboard petrol, that is)

[Alan]

an 8.5m Scorpion with a 415hp 7.4L inboard?! Fast enough I'dve said!!

I read somewhere that Merc's are still being sold and warranties honoured (which is a relief having a 6 month old Opti!) by Marine Power Europe. The only other engines to consider are the Yamaha HPDI (as on Blue Ice). Nice engines but expensive.

If you go for the Mariner/Merc opti make sure you get the smart gauges - tacho and speedo with secondary digital displays of fuel consumption, range, gph etc etc. Excellent bits of Kit!

Alan