any clue where's the log impeller on a moody 33?

syscode

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This is a novice question...

Got a moody 33 MK2 recently. When I tested it, the instrument showing speed worked fine.
Now it does not show speed - only 0:0. (a navigator2 by stowe)
The instrument make is:

I was told it's all, probably, a question of cleaning the log impeller.

Any clue where it might be on a moody33 mk2??

Cheers and many thanks in advance!

Sys
xx

*previous owner has yet to reveal the secret..
 
Look in all the lockers that lead to the hull. They are usually low down in the middle of the hull.

I got rid of my Stowe kit as it stopped working and parts were silly money.
 
Look in all the lockers that lead to the hull. They are usually low down in the middle of the hull.

I got rid of my Stowe kit as it stopped working and parts were silly money.

I had a look. Also tried to follow the electric line.. no joy.

Any better speed showing kit?

Cheers!
 
It will be wherever the person who fitted it chose ?

hummm.. in that case..
i was told it should be somewhere in the middle of the boat. usually towards the front just past the keel or some such..
again, no joy. (hence thought maybe moody has a special trick.. maybe it was a previous owner's private joke ;) )
Cheers!
 
Found any bits of the floor which lift? Might be under the floor in bow cabin. If you lift the boat out to anti foul you might find it from outside of course?
yup..
lifted all the bits that can be pulled up easy. not many on a moody 33..
indeed, it should get lifted sometime. Perhaps thats when the mystery will get cleared up.
Cheers!
 
If you have a look on YouTube you'll find videos of Moody 33s for sale, including ashore hull shots.
See here & here.
I know the heads are on the stbd side so inlet/outlet there, but I think I can see something that might be an impeller fairly far forward on the stbd side.
As others have said somebody on MOA forum will tell you!
 
It will very likely be forward of the keel to avoid influence, the 33 has quite flat sections forward so if possible I would mount a log on or near the centre line. It will also be mounted where it's accessible, so look in lockers and under liftable floor panels(also to be found inside lockers for added 'peekaboo! I see you!').
 
If you have a look on YouTube you'll find videos of Moody 33s for sale, including ashore hull shots.
See here & here.
I know the heads are on the stbd side so inlet/outlet there, but I think I can see something that might be an impeller fairly far forward on the stbd side.
As others have said somebody on MOA forum will tell you!

Hey - these are great links - thanks for the find.
Can see what seems to be a log.. In my moody there are pipes that connect with shower and toilet there.. Wondering if this apparent log impeller is in fact something to do with such pipes.

Regarding the MOA forum. They seem to regard this kind of a question as technical, hence with a bit of a pocket dive. (As a lifelong FOSS person, eg - lineageOS rather than android, fairphone rather than.. errr, almost anything else, a self run VPN rather than any paid options - the payment idea irks a bit in this context. shame IMHO :( )

Have a lovey day!

Cheers!
 
It will very likely be forward of the keel to avoid influence, the 33 has quite flat sections forward so if possible I would mount a log on or near the centre line. It will also be mounted where it's accessible, so look in lockers and under liftable floor panels(also to be found inside lockers for added 'peekaboo! I see you!').

Yes.
The general intuition is somewhere forward of the keel and towards the centre. There aren't many obvious options.. Will try again though.. Perhaps I missed something behind the cupboards in the toilet/shower..
IDK..

Cheers!
 
I can't speak for anyone else but when I have installed a log sensor I have always put it in a place where it is accessible without major demolition, as I have found that they frequently need access to clear blockages. First step is to loosen the lock collar and rotate the sensor left and right half a turn, whilemaking good speed through the water. This often dislodges seaweed or other detritus. The nect step is to remove the sensor from its carrier tube and apply the cap to the tube. Which is not exactly easy!

So the sensor unit should be easily accessible. Sometimes I have found them by following the cable, but this doesn't work in my present boat as the cable is in conduit along with others. In the end, you may only find the sensor once the boat is ashore.

Things that have prevented my system working have included :- massive barnacles on the impeller, small bits of wood lodged in the gap, thick antifouling, a broken vane of the impeller, and the magnets missing from the impeller. Apart from a VDO mechanical log, which uses an inner rotating cable in a tube, all my logs have been NASA units, either Target or Clipper. Cheap (sort of) and cheerful and reasonably reliable.
 
This has been mentioned, but just to clarify - a log impeller would have been fitted as an "after-market" accessory on a boat of this vintage. It would have been fitted in a place that seemed appropriate to the company or person that fitted it, and there is no generic location. There are likely locations - the preferred location is usually in front of the keel near the centre-line of the boat - and it is usual for it to be in an accessible location such as under a loose floorboard, as log impellers usually require regular cleaning. But there is no generic location.
 
Hey - these are great links - thanks for the find.
Can see what seems to be a log.. In my moody there are pipes that connect with shower and toilet there.. Wondering if this apparent log impeller is in fact something to do with such pipes.

Regarding the MOA forum. They seem to regard this kind of a question as technical, hence with a bit of a pocket dive. (As a lifelong FOSS person, eg - lineageOS rather than android, fairphone rather than.. errr, almost anything else, a self run VPN rather than any paid options - the payment idea irks a bit in this context. shame IMHO :( )

Have a lovey day!

Cheers!
I helped to set up the first version of the MOA Technical Library. This contains drawings which would answer your question immediately. You will no doubt have many more questions with a Moody of that vintage. It costs money to run a website, paid for by members. Like you I did not originally agree with charging for access, but came round to the idea.

When you have more difficult questions, as is inevitable, you may wish to reconsider, there is a wealth of info there, in articles, drawings and and a searchable database of questions already answered.
 
I helped to set up the first version of the MOA Technical Library. This contains drawings which would answer your question immediately. You will no doubt have many more questions with a Moody of that vintage. It costs money to run a website, paid for by members. Like you I did not originally agree with charging for access, but came round to the idea.

When you have more difficult questions, as is inevitable, you may wish to reconsider, there is a wealth of info there, in articles, drawings and and a searchable database of questions already answered.
And it's only £22 a year for heaven's sake, you can save that many times over using the info that's on there.
 
Definitely join the MOA - as cantata says, superb value, you'll get all the technical you'll need. On my M33mk2 the log is on the starboard side in the bunk locker just behind the nav table. Mine is a NASA and is a pita as it always fouls within a month of launching.
 
Hiyas!

Many thanks for all the ideas - helped eliminate options ;)

The log impeller was found.
Yay!!

Where?

Portside, front cabin, under a box installed under bagged extra sails.

A lovely day wishes to you all!

xx
 
Yes.
The general intuition is somewhere forward of the keel and towards the centre. There aren't many obvious options.. Will try again though.. Perhaps I missed something behind the cupboards in the toilet/shower..
IDK..

Cheers!
It won't be behind the cupboards, it will be on or near the centreline, as it has to work on both tacks when the boat is heeled, and will be in that area forward of the keel and not too near the forefoot, where there will be the least amount of turbulence. It will have a wire lead into its top and a knurled "nut" for undoing to remove it. It's likely to have a blanking plug close by, to stop the inrush of water when you do remove it. If you have a depth instrument, you will also find the the depth transducer close by, but that will not be removeable.
You will need to remove it before liftout as it could be damaged by the lifting strops. If you want to have it working while you are sailing, it's better to remove it when the boat is not in use, so as to keep it free of fouling. Someone on another thread mentioned "special antifouling for transducers" but did not go into detail. I asked him to elaborate, but I have seen no further contribution yet. Edit; Here it is:
Marlin Eco Transducer Antifouling | Force 4 Chandlery
When you do find it, have you rblanking plug ready, unscrew the nut, take a deep breath, pull it out, and ram the blanking plug in as quickly as possible, ensure that whatever mechanism keeps it in place is working, then go and get your bucket and sponge........
Regarding your question about replacing it with something better; if you type the words; "buy speed/log instrument" into Google, it will lead you to a plethora of such equipment. To find out about the best value for money, read the reviews, or ask on here.
Edit :
Here's a PBO article re keeping your speed/log transducer clean:
9 ways to keep your log impeller fouling-free - Practical Boat Owner
 
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