Hydrofield 6.6 and Yamaha F250 Engine Heights

[rocklobster]

Just wondering if anyone out there has a 6.6 Hydrofield with a Yam f250 . I am interested in what engine height and prop size , blade type and pitch you are running .
Thanks in advance

[frankgrimes]

Hey mate *think* Mat(business class) has a 6.6 hydro(Or close to it)....worthwhile flicking him a pm.

Mick

[rocklobster]

Thanks Mick

[business class]

I have a Hydrofield but is a custom built one and is 6.8 in length. I run a 225 honda and had it set up for the kind of fishing i do. Spaniard King on here set it up for me with pitch and size, its a 16 inch 3 blade stainless and is awesome in preformance. The trasome height needed to be raised as there really low on the hydrofields but I got this done when we did the cut and shut. Otherwise a spaceing plate may be the answer as thats what we had before the extension to raise the engine. Im guessing your finding your underpowered at take off?

[rocklobster]

Hi Matty,
No definately not underpowered. I have new offshore 250 and am still playing with props. I have read about your boat and have seen the work you have done It looks like a labour of love . Previously i had an F200 that did the job okay and i was running a 3 blade solas 14 and a quarter x 17 and it did the job reasonably well . I have currently borrowed a 4 blade 14 x 17 four blade prop that has made quite a lot of change to the boat . I feels as if it rides higher in the water and feels very "grippy" however i am only running 5600 rpm at full throttle . Four blade props can be run higher than a three and this weekend i will raise it one hole to try and pick up a couple of hundred revs.I am not totally sold on a four blade prop and am reluctant to drop to a 15inch pitch until i have explored all options .

[Smithy]

A local commercial operator here just blew up both his Yammie F250 gearboxes at around 3,800 hours and it is looking like the 4 bladers and the extra weight to spin them might be the culprit. At those hours they were just getting sad and starting to use a bit of engine oil. They went back to 3 bladers at the end and were doing some figures on oil used and fuel used even though both lots of props were right as far as WOT etc. were concerned. That was until both boxes let go on the same day. He was spewing as you could well imagine. What are the chances of that! He is now sworn off 4 bladers and back running 3 bladers on the new V6 block Yammie 250s he has put back on.

[julian1]

carrying heavy loads was he Smithy ?

[rocklobster]

With That amount of hours anything is possible, two on one day? Maintenance is in most times essential and for working engines a must . It would be a good excuse to repower at least that is what i would tell my wife .

[Smithy]

Not particularly Julian. He is certainly on a 12month replacement program now after doing the sums. I guess once the one went and he was limping back in on the other it put too much strain on it. He is getting boxes in from the US. None over here anywhere. Maintance was spot on with the same guy I used to use.

Interestingly even though these new V6 models are suppossed to have more torque it dies in the arse a lot more downsea on big swells. Fuel economy is out of sight. Probably 20% better at least. Pushing a big NC he would be using 60+litres an hour combined for 20knots. These new ones are only at about 3,200rpm for low 50s an hour combined for 20knots. They are just loping along but must not be in a happy place in the torque band. Range is over 260Nm with some margin for error as well. Has taken a bit of time to get used to them but now he likes them. The new shift is awesome. No big clunk when you drop into gear.

[gofishin]

...Interestingly even though these new V6 models are suppossed to have more torque it dies in the arse a lot more downsea on big swells...Is he using smaller props Smithy? New ratio 1.75:1, old ratio 2.0:1. Depending on prop type & diam, a 2 to 3”reduction is required otherwise you’re way down on WOT.