I am looking to get a new depth sounder for my Parker 31. The existing (original) Stowe instrument is not working well.

I don't see any readily available item which will go in the existing through-hull hole. The choice seems to be a simple NASA instrument (the display part will fit in the space on the instrument housing) or something from Raymarine which will cost hundreds of pounds more. It seems that with the NASA one I would need to mount the transponder inside the boat and it is supposed to work properly through the hull.

Has anyone fitted such a thing to a P31 or got any useful advice about mounting the transducer inside the boat? Thanks.

Pat
I replaced mine a couple of years ago with the NASA unit, a more economical option. The display fitted existing cut out no problem. With regard to the transponder, it was fitted inside and works well. Replaced the speed unit at the same time , as both units displays were increasingly difficult to read.

Hope it helps

Chris

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Thanks Chris.
I was hoping it was going to be straightforward. I will go ahead with the NASA instrument.
Pat

Chris,
Did you use the "In Hull Transducer Mounting Kit" which you can buy as an extra? Or did you bed it in mastic or what? I gather there must be no air bubbles between the transducer and the hull.
Thanks, Pat

Pat
It was done by Upson’s yard, as they replaced the speed log unit as same time, as removing the old log unit’s through hull fitting kit and cutting new holes in the hull is a job I leave to the professionals!

A mounting kit was used, I have a feeling they put oil in the tube for the transducer to sit in, I would go and check but have just arrived in Caribbean for a couple of weeks.

Hope this helps

Chris

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Hi,

I'm just tagging along on this post to keep everything in one place.

I've recently bought a Parker 21, which I'm keeping on a mud swinging mooring on Chichester Harbour, that has no working electrics. I bought along a motorbike battery to test things but nothing appears to work bar the VHF radio (although I have no antenna). My main priority is getting a solar panel to keep the motorbike battery charged and to sort out the depth sounder that doesn't appear to work. I was wondering if the transponder can be replaced from the inside (once dried out on the beach) or if it needs to replaced from the outside-in..

Also. from these images can anyone tell me which is the transponder and which is the log?

As for the solar panel, there is a pre-existing panel that has been disconnected and there is no controller. Would any type of controller do and do I just connect the controller direct to the battery. Or is it better ripping it all out and starting with something like this? https://uk.renogy.com/products/200w-12v-flexible-solar-marine-kit-w-20a-voyager-waterproof-charge-controller 

Any help/advice would be much appreciated.

Many thanks
Manuel (Galadriel)

Hello Manuel,

I had a similar set up when I bought my 325 - I think Bill Parker went with the same NASA log/depth for all builds.
I replaced the log with a combined log/depth/temperature(!?), which meant widening the log cavity and just leaving the depth sounder in place.
From memory the black item is the depth, and the red is the log. The metal bar is to help you get leverage when you unscrew the log - it does unscrew.
Somewhere on board you might find the blank that screws in to close the hole left when you unscrew the log. I've done it afloat, and it's slightly scary but if you're quick it's surprising how little water comes in. Try and hold a towel or cloth over the log so the water doesn't spout everywhere. Otherwise wait until the boat's aground.
Because of fouling on the paddlewheel some folks replace the log with the blank if the boat isn't being used for a while - I never did!
If you can't find the blank on board you might be able to buy one on eBay or even from NASA if they're still making them.

Best Wishes,

John Clack

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