Universal M18 leaking oil / low oil pressure

[Ralph Johnstone]

That line that Ralph asked about looks an awful lot like a sensor line for a manual oil pressure oil pressure (non electric).

OMG, you don't suppose this boat was built by British Leyland Motors in the UK with all their crap dashboard gauges. Oil pressure was a tube to a Bourdon tube pressure gauge in the dash. Speed and RPM were high speed rotating spring wire within cables which led to the dash (think engine stop cable.) There was also temperature readout but it was not electrical. It was as if they had never heard of electricity. Hopefully not.

As its a switch, i am assuming the PO didn't like not having a guage and added the box as an upgrade that later failed catastrophically (note the wobbly reconstructed side)

If wobbly is the case, I'd suggest removing the box and consider any "T" joints be done with solid piping (1/8" NPT) or other small but solid assembled piping.

If you can supply answers to questions by others along with an overwhelming number of pictures dealing with these areas, this would go a long way to solving this mystery.

Just remember, never in the history of SBO has anyone ever said "Hey, ya got too many pictures." Never happened.

 

[Ralph Johnstone]

Could this be with a 3 pin sender which sends pressure signal and a 8 psi warn?

I have heard about a sensor which is both a pressure sender and a pressure switch. Happy Googling. Make sure everything matches you boat's wiring for the switch and the new temp. gauge which you will purchase.

 

[smokey73]

If you are concerned with the block modified by the PO you can probably replace the block with a more compact Tee as long as the block doesn't serve some other function. I'll post some pictures of what I did with my Yanmar later.

 

[Ralph Johnstone]

I'll post some pictures of what I did with my Yanmar later.

That's been my problem here. The PO has a Universal M 18 and I've got a Yanmar. Two different worlds.

I wish @Stu Jackson would let us know when he goes on vacation. No consideration at all.

 

[smokey73]

Not so much a Yanmar vs Universal engine issue. Just an example of how an adapter or T could replace the big, clunky "box" as you suggested

My adapter had one male BPT that fit into the location of the original pressure sensor. (ordered from McMaster Carr). Yanmar used BPT threads for the OEM sensor. The adapter had two NPT female connections. I put in the replacement (non-OEM) sensor with male NPT connection into the adapter. The matching electric oil pressure gauge was placed at the helm where the original oil pressure gauge was. I also atached a metal weave female NPT oil line hose into the other NPT female location. I then ran the oil pressure sensing line to a mechanical gauge I put in the engine compartment (it is there for reference to the electric gauge at the helm should I think I have a problem.) The poster could adapt the same concept hooking his adapter into the original location of the oil sensor which now has a hose that feeds the block.

 

[Ralph Johnstone]

Could very well be. All depends on just what's hidden in that Pandora's box. Unless it serves some unseen purpose, I would say it's got to go.