Raymarine Log & Wind Speed "stuck"

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SiteSurfer

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About to sign on the line for a B36, this is kitted with a Raymarine Tri Data, I'm not familiar with the brand so a couple questions.

The masthead windspeed spinny unit (the cups not the vane bit) appears to be stuck, is this common and if so any devious way to unstick aside from climbing up the pole? The direction is registering fine. Its a long way up there...

The log is a bit stiff and doesnt rotate freely - and does not register at the helm when spun, now I'm certain that these things are bullet proof almost so not too concerned as it will probably be a loose wire but just in case - any techniques for freeing them up (vinegar?), theres no obvious fouling and its out of the water at the moment. Come to think of it - the depth one wasnt working either...

The head unit is turned on and live, so I'll back trace the fault, its mainly whether these units are known for bearings wearing out or whether its a common thing to have them sticking. My NASA equipment on previous boat never got stuck so not experienced this before.
 
The bearings in the wind MHU will have seized. I'm afraid that there is no alternative to removing it but, if you are willing to purchase a new one, it's one trip up the mast without any tools so, technically, it's an easy job. You can bring it down and change the bearings but that will mean 2 trips aloft and then there's the issue of the masthead connection getting wet during the repair period. There is supposed to be a plastic weather cap on the fixed part at the masthead but that part on mine had long since vanished.

See http://www.ybw.com/forums/showthread.php?503812-Which-Raymarine-Wind-MHU-in-photo

Richard
 
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Agree that that the bearings will be goosed. I also recently did this job...it's actually fairly easy DIY, but I also imagine fairly easy to break something. I actually forgot to cover my masthead connection when my MHU was down with no ill effects so it's no biggie. Although that was during the hottest summer on memory!

Before I "signed on the line" I'd be asking for it all to be fixed. If the MHU is goosed, it's very expensive to replace...circa £500 IIRC (bearings and cups on eBay for much less, although someone on here did find a cheaper source...not sure if it was in RichardS's thread as I did not read it). Ditto do you really want to be swapping transducers and running cables back? If you are using a modern plotter like an Axiom which is doing all kinds of clever stuff like projecting wind and tide onto the plotter screen itself, if any of this stuff is not working it's going to give you really odd data.

It might be simple fixes...but it could also be a total PITA and very expensive.
 
Wind Vane: As others have said sounds like bearings shot so it's a trip up the mast but those things are simple to take off. Like almost everyone else, I don't have the cap which blanks off the terminals, so take a small plastic bag and rubber bands up there with you. If you want to DIY the bearings are about £50 but there's a bloke on ebay will do for you for £100 (search on ebay for "raymarine fixed price bearing replacement".

The service centre will also do these for you. Cups and bearing replacement and service was £192 last year with return postage

For paddle wheels I used the following approach:
* use a small drift to knock the pin which the wheel sits on through
* clean it up with some fine grade wet and dry
* this will give you the opportunity to better clean the paddle itself
* reassemble just by knocking the pin back through
 
Cheers folks, some immediate stuff for me to look at there.
Iain C - you have pretty much voiced my concern, I'll have to have a chat about it.
 
Also - just spotted a bit of an error in my post, the Tri-Data is, of course, a separate unit to the windspeed indicator - the wind speed shows the wind angle but not speed and the tri-data shows .. well... nothing really :)
 
SiteSurfer said:
Iain C - you have pretty much voiced my concern, I'll have to have a chat about it.
Click to expand...

Chances are it's an easy fix but I'd certainly not risk taking it on without a price reduction to cover a worst case scenario or it working properly before you sign. If you do decide to DIY it, make sure you know which MHU you have. My B32 is 2004 vintage which has the older ST60+ MHU, an aluminium tube as the sender unit and trapezoidal cups, not the shorter one with ellipsoid cups.

Like you I'd also come from a NASA equipped boat and the Raymarine stuff is very different. It may be worth a poke behind the binnacle to see if all the Seatalk cables and earth wires are connected properly. It's not a case of a simple co-ax cable like your NASA one. Is the log displaying sea temperature? If not, plus your paddlewheel isn't sending when you spin it, you probably have a trickier problem or a dead transducer. It may have a small water leak as this can happen according to RM.

Once you have all the stuff fixed and working, it will all need calibrating. The wind sensor for example does not have a "default" keyway on the ally tube. The instructions are online but there's lots of motoring in circles to calibrate the wind, plus find some slack tide or a locked marina for speed. You may also want to calibrate your autopilot if fitted, and turn the sensitivity down which uses a lot less power and steering input.

My instruments, which were in a similar state to yours by the sounds of things (only needed MHU bearings though) were in a right pickle calibration wise when I got the boat (30 degree conflict between the AP and the steering compass for example), but now it's all up and running they are brilliant. Everything talks to everything else, the pilot will steer to wind, heading or track, and the Axiom I have fitted at the wheel is a great bit of kit that shows the boat icon with the correct heading, course, wind and tide speed and direction. You will find it a big jump up from your NASA kit!
 
My super trusty NASA wind vanes stuck after WORKING WELL ( for the anti NASA brigade!) so up the mast I went I found that there was a mossy sort of growth under the arm, I cleared this out with my screw driver and sprayed some wd 40 inside. It is still working another year on.
 
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