Islander 28 - Original depth transducer in oil bath?

[joelozzy]

I'm currently on the hard replacing a couple thru-hulls and just realized where my depth transducer is located: under the starboard settee, next to the waste holding bladder in a half-dome fluid bath. There is no thru-hull fitting, which is great. But the dome is glassed into the hull.

I'm wondering if anyone with a similar setup has re-used this bath with new depth transducers? I've specifically got the Raymarine ST-60plus.

Also, what fluid would you use for the bath? Appears that the fluid in there is green glycol.

[Paul Comte]

The 1977 i28 I crew aboard has its depth transduce installed in a tube under the port settee, immersed in mineral oil. I am not sure what bonds the tube to the hull but it has held for 34 hard sailing years...





Paul Comte
Milwaukee, WI

[joelozzy]

Thanks for the info. Yes, I'm trying to avoid adding another thru-hull to my existing 6-hole (soon to be 7) inventory. And I've since found several articles that explain the 'no thru-hull/bath' method. Looks like Castor Oil is the fluid of choice. Now to select a suitable location that is easily accessed...

[Skipaway]

Offered not as a recommendation, but as a reference to another alternative.

I've got an old Standard Horizon depth finder with what looks like a transom mount transducer. Some prior owner cut a hole in the head sole and put it there with what appears to be silicon sealant. The hole is covered by the cut-out. It works, when I'm paying attention.

(I keep looking at that hole and think about shower drain possibilities.)

- charlie

[joelozzy]

Unfortunately I've got no extra room in the head to floor mount the 'ducer. Barely enough room to drop a deuce! Finding an area to mount this that is somewhat protected while still allowing me access is proving difficult.

Will keep looking around as I finish my work in the boatyard. Could easily drill this puppy and be done with it, but why add ANOTHER thru-hull, ya know? I've already got 7 (engine intake, septic outfall, raw water in & sink for kitchen & head, water speed 'ducer). Assuming that's typical (???).

[Paul Comte]

I think it is hard to beat a nice "short run" installation under the galley sink.

It has lots of advantages and only one "dis", it's already tight in the galley.

On the plus side; power is right there, the data cable run is short, it is possible to mount it aft in a nearly useless and filthy space, it is near the center line and thus almost for sure going to be reading the bottom.

Your milage, nautical and otherwise, may vary.

Paul Comte
Milwaukee, WI

[joelozzy]

Still not sure what method I'll use to secure to the hull, oil bath or epoxy in butter dish. But will re-examine the 'under sink' area. Awfully tight with 2 thru-hulls and 2 bilge hoses (auto pump & whale backup). Getting a hammer in there to pound down a plug in case of emergency would be tough.

The engine compartment has room, but difficult access. Plus lots of vibration from the engine (I'll be re-powering next year) and associated heat and blow-by exhaust fumes. Not electrical friendly.

I've already drilled wire-chase holes for the water speed 'ducer coming aft from the forepeak locker. My strongest inclination is to install depth adjacent to this 'ducer.

Will re-evaluate in a couple days when the holding tank replacement project is done. Didn't realize that the Ronco tank & thru-hull would be so difficult to install. Had to glass over the original thru-hull hole & install the tank prior to re-installing the thru-hull fitting. Good thing is I'll have space to mount an in-line gusher pump & y-valve in the same compartment, under the starboard settee. Will be glad when this is done.

Tough project. Couldn't see how difficult it was going to be until I hauled out and removed all existing pipe/tank/thru-hulls. I've been taking pictures, if anyone's interested I can share when done (hopefully soon).

[nsa_sailor]

We replaced ours with a Humminbird unit that epoxies to the hull, next to the engine water intake under the starboard quarterberth. Never could get the the Signet Speed/Log/Depth to read the depth. This one works great.