Electrical issues

[Barn Free]

Good morning; I’m new to Trawler Forum so pardon any errors. We have a 1988 President (Taiwanese) 43’ motor yacht. Recently my husband changed the oil on both engines (2) ( 275 Hp diesel Ford Lehmans) as well as the generator. After completion, he started the engines to check oil pressure. Although it started right up, the starboard engine showed no oil pressure, less than 8 volts on the battery gauge and the fuel tank registered almost full although it only has about 1/4 of a tank. He’s crawled around the engine room checking connections, etc. but doesn’t see anything amiss but obviously something’s off.
Anyway, would appreciate any suggestions, trouble shooting ideas, etc.

 

[RT Firefly]

Greetings,
Welcome aboard. Good possibility your husband "bumped" or disturbed some wiring. Great excuse to check and clean all electrical connections especially the ground wires. Some times it's that one hidden/difficult to get to spot that gets overlooked or one seemingly useless wire that gets removed (inadvertently).

 

[O C Diver]

If it were my boat, with a digital multi meter reading DC voltage, I would restart the engine and measure voltage at the battery and then at the gauge panel. If battery voltage is above 10 volts and the gauge panel meter is still at 8 volts, I would suspect a negative wire issue between the engine and the panel. Worth noting: starting the engine at the panel doesn't require the negative wire, only a positive wire for both the run circuit and the start circuit.

Ted

 

[Barn Free]

Hi;; he’s cleaned the connections and tried to look at all the places he was moving around; using a mirror for awkward, tight places but still no luck. He’s still poking around.
Thank you for the response and appreciate anymore suggestions.

 

[O C Diver]

What does the voltage at the battery measure?

Ted

 

[Barn Free]

He’s going to borrow a meter and check that and I’ll let you know. Thanks.

 

[Bmarler]

A meter is a must have item. You can’t fix things without tools. Even an inexpensive meter from harbor freight it more than adequate for most boat use.
Plus, a meter lets you know when a circuit is truly shut off and safe to work on.

 

[Barn Free]

We’ll get one. Thank you.

 

[TBill36]

Owning an older vessel is going to take at least rudimentary knowledge of how electrical and mechanical systems work. I'm not trying to sound condescending, but not owning a multi-meter indicates that knowledge is lacking. You need to become close friends with someone that has that knowledge or that boat is going to cost you a fortune. Also, buy books and watch videos on basic boat instrumentation and mechanics. Nigel Calder has some excellent books as a place to start. Hopefully others will chime in on suggested readings and other sources.

 

[jgwinks]

With the fuel gauge reading too high it sure sounds like a ground issue. Gauges read resistance on the ground side and if you disconnect the ground completely they'll either read full high or full low depending on the sender. I think you've got a loose ground connection someplace. Look for a smaller wire, probably black or yellow, bolted to the engine block. Also check the wires on the gauges themselves. A fault there wouldn't have anything to do with changing the oil but the timing may be coincidental.

 

[RT Firefly]

Greetings,
Ms. BF. Excellent suggestions by Mr. TB (post#9). Might also, at some point, be of some advantage to hire an AYBC licensed marine electrician to get some "lessons" on proper wiring termination(s) OR make friends with someone who is learned in MARINE wiring. Boat systems and home/automotive systems can be very different and if not completed to MARINE standards can be quite dangerous.

 

[Barn Free]

Hi; he has a voltage meter; just can’t locate it. We’ve had the vessel over 8 years and do most of the maintenance ourselves and are very aware of the quirks in owning an older boat. Thanks for the reading suggestions.

 

[RT Firefly]

Greetings,
Ms. BF. Apologies. I thought this was a new, to you, boat not just new members.


Other than what I suggested (inadvertent bump/disconnection of wiring) there is nothing I can imagine that could possibly associate an oil change with electrical problems.

 

[26permacraft]

Kudos to your husband for tackling the oil change. I'd double-check the oil filter and connections – sometimes, those sneaky air bubbles can mess with the pressure readings. Also, any chance the oil pressure sensor got a bit wonky during the oil change?

 

[Barn Free]

With the fuel gauge reading too high it sure sounds like a ground issue. Gauges read resistance on the ground side and if you disconnect the ground completely they'll either read full high or full low depending on the sender. I think you've got a loose ground connection someplace. Look for a smaller wire, probably black or yellow, bolted to the engine block. Also check the wires on the gauges themselves. A fault there wouldn't have anything to do with changing the oil but the timing may be coincidental.

Yeah; he mentioned that maybe it was a coincidence. He’s at our farm and I’m in town babysitting a grandchild so I’m reading the posts and things might be getting list in the translation. He’s anti tech ( owns a flip phone). I know he re- connected one wire but nothing changed but I’ll let you know how it goes after he looks again

 

[Barn Free]

Greetings,
Ms. BF. Excellent suggestions by Mr. TB (post#9). Might also, at some point, be of some advantage to hire an AYBC licensed marine electrician to get some "lessons" on proper wiring termination(s) OR make friends with someone who is learned in MARINE wiring. Boat systems and home/automotive systems can be very different and if not completed to MARINE standards can be quite dangerous.

Yeah; he mentioned that maybe it was a coincidence. He’s at our farm and I’m in town babysitting a grandchild so I’m reading the posts and things might be getting list in the translation. He’s anti tech ( owns a flip phone). I know he re- connected one wire but nothing changed but I’ll let you know how it goes after he looks again

 

[Barn Free]

We’re in Tennessee and pretty much know all the marine experts. We’ve talked to several and gotten suggestions; some the same as the ones in the posts, and have a guy coming out but even in winter, he’s 3-4 weeks out so that’s why my husbands looking around.

 

[Barn Free]

He’s headed there now so I’ll pass on your suggestions. Thank you.
We’re gonna stay on the boat tomorrow night so I’ll let him read all of the posts himself; being his long distance secretary gets tiresome. And he ain’t getting a better phone; trust me; I’ve tried.

 

[Barn Free]

Good news; he found the problem; it was a wire. He didn’t go into any details but knowing Barn Free, I have no doubt it was in a difficult place to get to. Anyway, all the gauges are back to normal. I appreciate everyone’s suggestions and input.

 

[TBill36]

Reading the initial posts, I assumed he didn't have a multi-meter and hence my comment. I apologize and being a farmer, I'm sure he's pretty knowledgeable with the basics and then some.

It's a little late, but too bad Santa didn't get him a cell phone.

 

[Barn Free]

Even if Santa brought him a new phone, he’d send it back. He LOVES his flip phone. Thanks again to everyone for all of the good suggestions. Salud until the next boat issue.

 

[RT Firefly]

Greetings,
In total agreement with Mr. BF. Cell phones are the devil's distraction. Flip phone works just fine.