Raymarine wind speed slowing down

**wiggy** · 12-11-12, 19:02

I've noticed that my mast head unit is getting slower and slower compared to my neighbouring boats, often recording no breeze at all. It's about 12 years old, any suggestions for a mast up maintenance solution ( quite happy to go up the mast ).

**pvb** · 12-11-12, 19:05

Originally Posted by wiggy

I've noticed that my mast head unit is getting slower and slower compared to my neighbouring boats, often recording no breeze at all. It's about 12 years old, any suggestions for a mast up maintenance solution ( quite happy to go up the mast ).

You need to take it off, check/lubricate/replace the bearings, and put it back.

**Jabamusic** · 12-11-12, 19:09

Yes, mine is doing exactly the same. I did lubricate it last year which helped, but clearly not for long :-(

From the depths of my memory there was a post years ago which detailed the replacement of bearings. It involved a major dismantling process ie cutting or drilling into the head unit to access them. Once in, I seem to remember that swapping them out with replacements was neither difficult or expensive.

I'll see if I can trace the post down.

**Martin_J** · 12-11-12, 21:47

ST50 I guess then.. Check out a few of my previous postings for photos.

If you lubricate (as the easy way out) I would suggest that you don't use an oil. However light a machine oil it is, it will still be too viscous.

If anything, try something like McLube Sailkote - expensive but slippery stuff.

Replacement bearings perhaps £10.. Replacement unit maybe £300...

**Stoshak** · 13-11-12, 09:03

Mine suffered from the same symptoms. We had to resort to tanging the backstay to activate it. It had been untouched since installation in 2005.

I took the mast down last month and took the anemometer home (Raymarine ST60 with cylindrical gubbins as opposed to later spherical)

When I removed the rotor I noticed lots of dusty powder within the hub, and the little drain hole was blocked. The design is such that hub will collect rainwater.

I cleaned it all out and gave it a squirt of WD40

It has since been rotating faultlessly on our washing line post test installation.

So the bearings may well be OK!

**paulrae** · 13-11-12, 17:43

"I cleaned it all out and gave it a squirt of WD40"

Following similar symptons on my ST50 wind some time ago, I did the same. It didn't work for long. After hacking around for a while, unsuccessfully trying to remove the bearings I got in touch with Stowe Marine/Tinley Electronics. They advised:

"Please note: WD40 on PCB may damage components".

In any case, if you're as ham-fisted as me, it may be worthwhile getting someone like them to have a look at it. It won't be cheap, but if it's repairable they'll do it.

**Stoshak** · 13-11-12, 18:49

I thought I had made myself clear.

I did not dismantle anything. I removed the anemometer rotor and cleaned its interior. The WD40 helped in this.

The bearings are sealed, and the electronics are within the casing, also sealed by O rings. So the WD40 will not have accessed anything delicate.

In any case I do not share your fears about its affect on PCBs

However, I would be interested to know if Stowe Tingley managed to replace the bearings and if so how much they charged.

**skyflyer** · 13-11-12, 21:49

Theres been a few posts on this and so when I did the job recently I took some photos, hope these help or at least give an idea of what is required.

**Stoshak** · 14-11-12, 07:54

Brilliant! A very kind and useful posting.

I shall have a go. Anemometer is still working well in the garden, but a set of bearings will avoid a trip up the mast in future.

Where did the hair come from?