Jefa Steering, vibration on wheel under engine

[Dave 71]

Hi all, just after a bit of advice/reassurance/suggestions

I have a 2008 Hanse 320 with Jefa steering. Over the past couple of months, I have noticed a vibration on the wheel whilst under engine. (I suspect its always done it, and not registered in my head, or I've not been at high enough revs to notice before, but it's something I've noticed more recently)

Vibrations start at about 2000 rpm, gets more noticeable up to about 2500 then seems to stay the same above that. Below 2000 rpm nothing to speak of.

I'm assuming (well hoping) its normal and simply the wash from the prop feeding back through the rudder and steering, although it doesn't seem quite right somehow and there's an occasional metallic clank from inside the pedestal which makes me think something isn't quite right and that it might be a symptom of something wearing out.

I'm 99.999% certain it doesn't happen under sail, I don't recall noticing it under sail - but I wasn't able to test this on Tuesday due to lack of wind.... but tried to simulate that by building up speed, going into neutral and coasting - no vibration. So it certainly seems linked to engine/prop wash. Boat has a saildrive and a 2 bladed folding prop.

Steering response is fine - great in fact, boat turns on a sixpence.

Any suggestions as to what to check and investigate?

 

[Dave 71]

Edit: one possible thing.... thanks to my own stupidity I didn't properly unscrew the hub that locks the wheel first time out in the spring, took me a while to twig why the steering wheel felt stiff. So that's something I'll look into anyway.

 

[Boater Sam]

Prop fouled?

 

[harvey38]

+1 for fouled prop.

 

[Neeves]

Secure the yacht to its pontoon and or mooring - run the engine in gear, forward and or reverse - if the prop is fouled you should feel it through the yacht (not only the wheel).

If you have something round the prop poly bag, rope you should be able to see it simply looking if the water is clear - or use a bathyscope (or stick your head under with goggles on). If you have an underwater camera - stick it under the water, point at prop go, click, click , click and one of the pictures will show the prop. Or a variation on one of these themes. You don't say where you are but if its warm (and clean enough). - go for a swim. As its a folding prop - maybe one of the blades is not opening properly (howe long since the prop was anti fouled?).

If its a poly bag they can sometimes be removed running the prop at 'cruising' revs in forward and then reverse. if its rope you need to lift or swim. If its rope running in forward and reverse might make it worse - look first.

Fouled props are not unusual - just a big nuisance.

Jonathan

 

[wilkinsonsails]

Jefa are very helpful when you explain a problem They upgraded a very ratteley system on a Discovery 67 for us .The linkage between the wheels had the joints replaced which stopped the problem of vibration at the helms .
We also had Some occasion clonking noise came from the Jeff autopilot linkage on another Hanse 400 we looked after .
It had been incorrectly installed from new ,and the helm link jack knifed on helm over as the rudder lifted slightly.

 

[scottie]

Possibly of propeller damage?

 

[Spirit (of Glenans)]

Possible wear in lower rudder bearing. That's what caused my rudder to flutter while sailing over five knots, and always when under engine when revs above tickover.

 

[Dave 71]

ok, Thanks all.

I hadn't considered a fouled prop, something else to check. I'll run the engine up alongside and see what that tells me.

Local water is now a bit chilly for swimming and is really liquid mud with silt in suspension rather than 'water' so I doubt a camera will reveal much - but lifting out shortly in any case