Water spraying out side of prop area?

[themerlin]

Any one know if this is an issue or not, when under way and look back there is a spray shooting out the back of the boat from the prop area, normally only happens with a light load so I'm guessing the prop is a little high out the water with these loads,doesn't seem to cause any problems I am aware of.

[Axl]

Re: Water spraying out side of prop area?

Is it the transducer bracket?

[gazza2006au]

Re: Water spraying out side of prop area?

its normal for older outboards to leak water from the gearbox to exhaust housing joint as there is no seal to buy for this

[themerlin]

Nah it new, it's not leaking from anywhere I just think the prop is throwing it up, maybe the cav plate is too high when the boat is light.

[johncar]

Re: Water spraying out side of prop area?

Too Deep or too shallow can make it throw up water. If it is not tending to cavitate I suspect it may be running too low.. Your Cav plate should be just skimming the water at speed and at optimim trim and shouldn't throw up any water. Be very careful if you decide to check this while under way but it is the best way, try and get back there and have a look to see where it's coming from.

[chris69]

Re: Water spraying out side of prop area?

Have you got a anoid on the cave plate and is it straight?????

[WalrusLike]

Have you got a anoid on the cave plate and is it straight?????

I am a novice motor boaty so maybe I am wrong.... But aren't the anodes deliberately angled to partially offset the props tendency to turn to one side. Something to do with the angular momentum of a spinning object.

[Noelm]

Re: Water spraying out side of prop area?

kind of hard to be exactly sure on what you are asking, but if you mean there is a spray coming off the leg out both sides, in a sort of "V" spary, then the motor is too low, seen it a thousand times, but if that is not what you are saying, describe it in a little more detail. Alos post a picture of the rear of you boat showing the motor in the running position, try to take it kind of level with the prop.

[Fed]

Re: Water spraying out side of prop area?

But aren't the anodes deliberately angled to partially offset the props tendency to turn to one side.

No mate the little fin is to offset engine torque.
Looking from above your crankshaft spins clockwise, the opposite reaction is for your engine block to turn anticlockwise to the starboard.
The fin is set to the starboard to push the engine back towards port.

Prop torque, when looking from the rear your prop will spin clockwise, the opposite reaction is for your hull to try and spin anticlockwise or lean to the port.

Added to that, over trimming or under trimming will change the attack angle of the prop blades from one side to the other resulting in a completely new force applied to the steering.

[WalrusLike]

Ah... Thanks for that. So when you say it's set to starboard does that mean the leading edge is to port to generates turning force to starboard?

[Fed]

Re: Water spraying out side of prop area?

Yes, the leading edge to port and the trailing edge to starboard.

Where you're confused is...
The fin steers the motor not the boat, then the motor in turn steers the boat.

It's sort of the reverse to what you would think at first glance.
The little fin is not a boat rudder.

[WalrusLike]

Mine had tiny pits in it... Presumably the electrolysis eating it.

How long do they normally last?

[Fed]

Re: Water spraying out side of prop area?

Normal usage fibreglass trailer boat could outlast the motor but I'm not sure with alloy boats because the outboard anodes actually offer protection to the hull as well.
Adding a SS prop would also use them up a bit quicker.
I have a mate with Yammys that have internal anodes that disappear in about 12 Months but I think there's something else going on there, he says it's great because it shows they are working but I say they shouldn't eat away so quickly. His motor, his problem, some people you just can't help.

[themerlin]

kind of hard to be exactly sure on what you are asking, but if you mean there is a spray coming off the leg out both sides, in a sort of "V" spary, then the motor is too low, seen it a thousand times, but if that is not what you are saying, describe it in a little more detail. Alos post a picture of the rear of you boat showing the motor in the running position, try to take it kind of level with the prop.

yep it's a "V" spray from both sides but only happens sometimes ,might depend on weight distribution etc

[Noelm]

Re: Water spraying out side of prop area?

yep, for sure, motor too low, might need to just come up a hole or two, it will vary depending on trim (sometimes)