Oil pressure problem or just the gauge?

Took a 10 min ride to the fuel dock the other day, and noticed the starboard oil pressure gauge was only reading less than 20 psi (port was at 40psi, where they both usually are). We were cruising at around 3400-3600 rpm, both engines seemed to be running great, and synchronized. Throttled down into the no wake zone, and the gauge was at 0. No smoke, no noises, engines synchronized. Fueled up, checked the oil (both clean and in the OK zone), and bilge (no signs of oil or anything abnormal). Started the engines back up and the gauge never moved off 0. Engines ran fine again on the way back.

I think it’s probably a problem with the gauge, sender, or wiring in between, but wondering if anyone has any other ideas or suggestions?

 

Thanks for the advice guys. I really appreciate it. I’m going to check it out today.

 

Oh wow..so the engine was running fine for a while with no oil pressure?

 

Ok thanks for the heads up. I’ll test the gauge and sender before I go anywhere. Hopefully, I get lucky and it’s one of those or the wire.

 

I just started both engines and gauges are reading 40 port and 20 starboard..so maybe it’s not the gauge..seems like I might have an oil pressure problem..wouldn’t know where to start with that. Might have to call a mechanic now.

 

I only pulled the wire off the sender, sprayed some contact cleaner on it. Wire brushed the post on the sending unit and put it back on. Once I saw a reading I figured the gauge is probably correct. Didn’t think about a dirty connection, maybe at the gauge, could result in a lower reading. I’ll remove the gauge panel and clean the connections. Then if it doesn’t change anything, I’ll try swapping the gauges. Thanks again Ron

 

I might be able to do that, if I can get the sender out. I was barely able to reach it to clean the connection. Maybe if I really dive in there. That would take the guesswork out. This is my first real boat, so I’m learning a ton - I don’t know how some of you guys work on these engines! Lol

 

Any advice or warnings about removing the panel with all the gauges on it? Looks simple enough - 10 screws...

 

Only access is if I take the panel off. Doesn’t seem difficult. The senders are really hard to get to, especially the port engine.

 

Ron - I Removed the panel with all the gauges in it. Was very brittle, corner piece even cracked off, but I can crazy glue it back on, no big deal. Cleaned up the connections, and tested the gauge, by jumping the sending stud to ground, turned engine on - gauge went to full 80 psi like I read that it’s supposed to.

I still might try switching the gauges. I guess I can “switch” them electrically, right? If I make jumper wires, to connect the sending wires to the opposite gauges, and leave everything else as-is. That would basically be the same as physically moving the gauges (which would be a major job), right?