Norwester
Member II
When I removed the infamous E32-300 electrical harness and ammeter from the original panel, I followed someone's idea of preplacing the ammeter gauge with a FARIA oil pressure gauge... and then waited to complete the job.
Twelve months later, we detected oil leak, possibly coming from the point at which the factory M-25 oil pressure switch is located, just below manifold on port side. Previous Owner (PO) had replaced this one switch with a 4-inch pipe nipple male 1/8-27 NPT with a "T" fitting to receive two switches:
#1 oil pressure switch to bullet light directly on the engine's cockpit panel above "oil" disconnected fan toggle switch.
#2 oil pressure switch to separate Piezoelectric Buzzer mounted near cockpit panel above fuel gauge (see pic).
When researching these switches and ideas for finally adding an oil pressure sending unit, I discovered a couple items:
Kubota engine female threads at this port are British Standard Pipe Threads (BSPT Tapered)) as reported by @newgringo
ericsonyachts.org
and @Kenneth K
ericsonyachts.org
So What? Well, it would seem an adapter to match BSPT and NPT is required.
While at my favorite local marine resource, (Nebar Hose & Fittings LLC: https://www.nebaronline.com/ )
I not only acquired the adapter off the shelf, but also an "X" fitting with four female 1/8-27 NPT threads to receive the existing two oil pressure switches AND one new oil pressure sending unit. ...
Does it all fit? YUP.
I also replaced the existing 4-inch pipe nipple with a new black steal one from Ballard Industrial: https://www.ballardindustrial.com/
Now, to reconnect and new-connect wiring from switches and sending unit and new pressure gauge. Faria gauge instructions were very helpful. https://defender.com/assets/pdf/faria/faria_oil-pressure_install.pdf
These were excellent resources if you're planning a similar install:
ericsonyachts.org
More on oil pressure switches:
ericsonyachts.org
Parts:
Faria, Oil Pressure Sender, 1/8 NPTF, 80 PSI, Single Station, Standard Ground
Sierra Single Station Oil Pressure Sender - 80 PSI - Sender Code C (1/8"-27 thread size)
Adapter with sealing-washer(NPT-female to BSPT-male)
4" black steal pipe nipple (male both ends)
"X" brass 4-female fitting 1/8-27 threads
Pics: pre-and post- conditions; M-25 oil pressure specs from service manual; panel.
Vid: short test:
Concerns? Just that the threads mismatching/crossing from P.O. 1st install of pipe nipple.
Question: Is the pressure gauge really worth the effort? It sure plugs a round hole in the panel!
Was your backside ever saved by watching this gauge?
Twelve months later, we detected oil leak, possibly coming from the point at which the factory M-25 oil pressure switch is located, just below manifold on port side. Previous Owner (PO) had replaced this one switch with a 4-inch pipe nipple male 1/8-27 NPT with a "T" fitting to receive two switches:
#1 oil pressure switch to bullet light directly on the engine's cockpit panel above "oil" disconnected fan toggle switch.
#2 oil pressure switch to separate Piezoelectric Buzzer mounted near cockpit panel above fuel gauge (see pic).
When researching these switches and ideas for finally adding an oil pressure sending unit, I discovered a couple items:
Kubota engine female threads at this port are British Standard Pipe Threads (BSPT Tapered)) as reported by @newgringo
M25 Oil Pressure Sender Threads
This was definitely a boring day. I just figured out that Kubota ie Universal Diesels use British Standard Pipe Threads (BSPS) which are very close to our NPT threads - but mostly different. Their Oil Pressure Sender "looks" like an 1/8 -27 NPT but is actually a 1/8 - 28 BSPT. Close! You can...
How do I add an Oil Pressure Gauge? Univ M25
My Universal M25 has the standard oil pressure switch and light. The red oil pressure light comes on when the ignition switch is powered and goes out once the block-mounted switch reads oil pressure. The switch and light currently work fine. I'd rather have an oil pressure gauge than just the...
So What? Well, it would seem an adapter to match BSPT and NPT is required.
While at my favorite local marine resource, (Nebar Hose & Fittings LLC: https://www.nebaronline.com/ )
I not only acquired the adapter off the shelf, but also an "X" fitting with four female 1/8-27 NPT threads to receive the existing two oil pressure switches AND one new oil pressure sending unit. ...
Does it all fit? YUP.
I also replaced the existing 4-inch pipe nipple with a new black steal one from Ballard Industrial: https://www.ballardindustrial.com/
Now, to reconnect and new-connect wiring from switches and sending unit and new pressure gauge. Faria gauge instructions were very helpful. https://defender.com/assets/pdf/faria/faria_oil-pressure_install.pdf
These were excellent resources if you're planning a similar install:
E32-3 - Adding an Oil Pressure Manifold and Gauge
I first posted on this subject in 2017 when I pulled the ammeter and the old charging circuit out of my Universal (M-25) engine panel. I wanted to replace the ammeter with an oil pressure gauge. This would require adding an oil pressures sender...
Remove and Replace Oil Pressure Switch, Ericson 381
Yacht cockpit instrument panels often have a buzzer that goes off when the ignition is turned on, then goes quiet as soon as the engine starts. The buzzer is wired to an oil pressure switch screwed into the engine oil reservoir. When the key is turned on, but before the engine starts, there's...
Parts:
Faria, Oil Pressure Sender, 1/8 NPTF, 80 PSI, Single Station, Standard Ground
Sierra Single Station Oil Pressure Sender - 80 PSI - Sender Code C (1/8"-27 thread size)
Adapter with sealing-washer(NPT-female to BSPT-male)
4" black steal pipe nipple (male both ends)
"X" brass 4-female fitting 1/8-27 threads
Pics: pre-and post- conditions; M-25 oil pressure specs from service manual; panel.
Vid: short test:
Concerns? Just that the threads mismatching/crossing from P.O. 1st install of pipe nipple.
Question: Is the pressure gauge really worth the effort? It sure plugs a round hole in the panel!
Was your backside ever saved by watching this gauge?Attachments
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