Level sensors and tank cap size

[joel]

The deck fills on my 49 are metric thread.

I installed KUS/WEMA NS5 NMEA 2000 senders in the tank inspection ports like others have done.

They are reasonable accurrate.

[pburka]

I'm also trying to install Wema sensors, but I don't think it's going to work. At least our tanks all have the same size inspection lids. They're the same diameter as 1.5" BSPP, but the thread seems to be finer.

[Gato Gordo]

I went through the same process on our Hylas 46 #25.
I installed sensors on all 6 tanks. None of the inspection treaded caps were the same. I was told the yard used what ever size was available.
I used Wema sensors. I drilled holes in the 6 inch inspection hatches for the installation and am
Happy with the installation. The only issue is with the one inch space between the bottom of the tank and the bottom of the sensor leaves a large amount of reserve after the sensor measures empty.

[Ambition]

On board Ambition like many Hylas 46's the standard installed system for measuring quantities in the diesel and water tanks is a Tank Tender www.tanktender.com Since the tanks (other than the large water tank under the aft berth) are far from rectangular, the Tank Tender measure content by inches. A simple chart of what an inch represents in the way of gallons or litres is not hard to accomplish - just tedious. It is simple to install and is really low maintenance. If you want know the thread size information for your tank caps  I suggest a quick email to Queen Long.
Merrill
S/V Ambition H46 #40

[pburka]

I'm trying to install level sensors in the diesel and water tanks on our Hylas 46, but I'm having trouble figuring out what size the caps are. The tank caps are not the same size as the deck caps, and they don't appear to match any NPT size, either. I saw somewhere (Facebook, maybe?) that they're 1.25" BSPP, but a 1.25" BSPP fitting is too small, and a 1.5" BSPP fitting seems about the right size, but the threads won't mate. I'm currently in the US, and of course nobody uses BSP fittings here, so it's hard to compare them to anything. Does anyone know what size these are??