Boat

Have Boat Questions? Ask a Boat Repair Expert.

Ask an Expert,
Get an Answer ASAP!

Boat

I've traced a ground fault to within my Yamaha 150 outboard.

Customer Question
But I can't figure out...
I've traced a ground fault to within my Yamaha 150 outboard. But I can't figure out where the current crossover is occurring. If I disconnect the main black electrical harness in the engine, the fault remains. If I disconnect the hot wires at the solenoid, it disappears. The smaller of the two red wires connected to the solenoid creates a full 12V ground fault, but I can't trace where that red wire goes. Nothing visually obvious wrong.
Submitted: 2 years ago.Category: Boat
Show More
Show Less
Ask Your Own Boat Question
Answered in 1 minute by:
6/8/2015
Marine Mechanic: Jason, Marine Mechanic replied 2 years ago
Jason
Jason, Marine Mechanic
Category: Boat
Satisfied Customers: 16,293
Experience: Degree in Marine Technology. Gas and diesel marine mechanic.
Verified
Hello my name is ***** ***** am I speaking with?
I don't quite understand what it is you are doing. What problem is the engine having that you are trying to correct?
Ask Your Own Boat Question
Customer reply replied 2 years ago
My name is Tom. Do you know what a ground fault is? I'm loosing current, through some unintended circuit. I've disconnected all the fuses to things like lights, horn, wash down pumps, bait aerator pump, radio, etc. So, none of the red (positive circuits) should be drawing current. When I attach a volt meter from the positive lead of the battery, to the (disconnected) positive wire that runs to the engine, I read 12 volts. It should read zero if nothing is drawing current, or completing the circuit (like I said, I've disconnected all other circuits).
Customer reply replied 2 years ago
Should I expect a reply, or are you done with this question?
Customer reply replied 2 years ago
(Posted by JustAnswer at customer's request) Hello. I would like to request the following Expert Service(s) from you: Live Phone Call. Let me know if you need more information, or send me the service offer(s) so we can proceed.
Marine Mechanic: Jason, Marine Mechanic replied 2 years ago
I don't quite understand, is the battery running dead on you when the engine sits, is that what is going on?
Ask Your Own Boat Question
Customer reply replied 2 years ago
I haven't noticed it running down when it sits, but I always turn off my battery selector switch. When running the boat is running at idle speeds, I notice that the voltage being received at my chart plotter fluctuates between 10-11 volts, which sometimes causes it to shut off. And the horn won't work. If I rev the engine, the voltage will rise to 13, and the horn works. After a day on the water, the battery is run down. Using my voltmeter, I tested for a ground fault, and see that I have one. And that takes me back to my previous statement, of having disconnected all the power drawing circuits (including the bilge pump), and still see current flowing across the positive lead.
Marine Mechanic: Jason, Marine Mechanic replied 2 years ago
What does the voltage read at the battery terminals with the engine running in the 1500-2k rpm range?
Ask Your Own Boat Question
Customer reply replied 2 years ago
Around 13.
Marine Mechanic: Jason, Marine Mechanic replied 2 years ago
Okay that's to low, you should be between 14.1 and 14.9, at 13 it's not really charging. Have you located the 50 amp fuse on the engine, an if so, is that fuse good?
Ask Your Own Boat Question
Customer reply replied 2 years ago
It is charging, perhaps a bit low. I'm reading the current coming out of the battery (not going in), so I wouldn't expect it to be much higher than 12-13.
Yes, the 50 amp fuse is ok. I notice that if I pulled that fuse, the ground fault disappears. I assume that fuse is between the alternator and the battery.Do you understand what I mean when I say a "ground fault". It's not a "short circuit", but rather a "minor" leakage of current from a positive wire to another ground somewhere.
Marine Mechanic: Jason, Marine Mechanic replied 2 years ago
Do you understand what I mean when I say a "ground fault". It's not a "short circuit", but rather a "minor" leakage of current from a positive wire to another ground somewhere.
I don't think you understand what a ground fault is. This is all DC electricity you are working this, there is no such thing a ground fault in DC. In AC, where you have 3 wires, a Hot a neutral and a ground. A technical "short circuit" is when hot touches neutral. And a technical "ground fault" is when hot touches ground.
Since this is DC electricity lets try not to use the word ground fault. It is improper. With DC circuits there are only 3 possibilities. An open circuit, a short circuit, and a functioning circuit. And that's it.
The problem you are having is your charge voltage is to low. It needs to be 14 or better. Run the engine again, ground the meter negative lead to battery negative, and then check voltage at the 50 amp fuse. does voltage come up?
Ask Your Own Boat Question
Customer reply replied 2 years ago
My chartplotter shows that it is only getting 10 volts from a fully charged battery. A short circuit would blow a fuse, an open circuit wouldn't allow it to turn on. Somewhere I'm loosing current (hence the term ground fault). I'm not making up the terminology. It's widely used in boating. It describes what I'm witnessing immediately (i.e., not after a period of time when a fully charged battery runs down). Thanks for the attempt to help, but I think its best to end this Q&A.
Marine Mechanic: Jason, Marine Mechanic replied 2 years ago
Your thinking of "Voltage Drop"....... Not ground fault. And really you are confusing yourself here because you don't understand what the words mean.
I will opt out.
Ask Your Own Boat Question
Ask Dominick Your Own Question
Dominick
Dominick
Dominick, Marine Mechanic
Category: Boat
Satisfied Customers: 1,009
1,009 Satisfied Customers
Experience: 25 Years Experience as Mechanic, 20 Yrs Boat Yard Owner/Mechanic, Factory Certified

Dominick is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here.

DianeDallas, TX

< Previous | Next >

Meet the Experts:

Dominick

Dominick

Marine Mechanic

1,009 satisfied customers

25 Years Experience as Mechanic, 20 Yrs Boat Yard Owner/Mechanic, Factory Certified

Ted G.

Ted G.

Rigger, Diagnostician

691 satisfied customers

40 years boating, Safe boating instruct., Offshore Race promoter, Failure Analysis, Expert Witness

John White

John White

Marine Mechanic

306 satisfied customers

11 years experience working on outboards, inboards, sterndrives & pwcs

Jason

Jason

Marine Mechanic

16,293 satisfied customers

Degree in Marine Technology. Gas and diesel marine mechanic.

Tan

Tan

MerCruiser Certified Technician

10,957 satisfied customers

40 yrs. experience with complete engine repairs both inboard/outboard and MerCruiser Certified Technician.

Jeff G.

Jeff G.

Marine Mechanic

4,728 satisfied customers

42 years experience, Certified Master Technician, All Major Outboards, Sterndrives, Hi-Performance

Captain Dave

Captain Dave

Marine Mechanic

2,672 satisfied customers

USCG Licensed Captain, 20+ Years Boating, Fishing, Maintenance and Repair Experience

< Previous | Next >

Related Boat Questions
It's a 1988 8HP Honda outboard and the throttle won't turn
It's a 1988 8HP Honda outboard and the throttle won't turn either way. … read more
Boat Doc
Boat Doc
107 satisfied customers
94 venom 200 I lost all fire so I changed power pack now
94 johnson venom 200 I lost all fire so I changed power pack now motor runs but does not plan out motor runs real bad if i unplug white and black strip wire it runs a lol better what could be any sugg… read more
Jason
Jason
Marine Mechanic
16,293 satisfied customers
I noticed this past month when I had my boat pulled for
I noticed this past month when I had my boat pulled for indoor storage at Smith Boys marine here in Buffalo, and they placed her on a work rack for me to clean and wax thoroughly prior to going inside… read more
Tan
Tan
MerCruiser Certified Technician
Certified Marine Technician
10,957 satisfied customers
48 no fire to plugs how do you check kill switch. Engine
48 Johnson no fire to plugs how do you check kill switch … read more
Tan
Tan
MerCruiser Certified Technician
Certified Marine Technician
10,957 satisfied customers
I have a westerbeke 30b3 on my boat. The engine cranks but
Hi, I have a westerbeke 30b3 on my boat. The engine cranks but won't turn over. I changed peimary fuel filter and bled the engine to the cylinders. I'm getting plenty of fuel up until the cylinders bu… read more
Jason
Jason
Marine Mechanic
16,293 satisfied customers
My engine will start by jumping solenoid but not by key
my engine will start by jumping solenoid but not by key replaced ignition swithch same thing ? … read more
Jason
Jason
Marine Mechanic
16,293 satisfied customers
I have water mixed with engine oil on a 3406b. My boat has
I have water mixed with engine oil on a 3406b. My boat has been sitting between seasons for 10 weeks a I found a small hole in the muffler. I drained the fluid out of the engine what should I do next… read more
Cat Man
Cat Man
Vocational, Technical or Trade Scho
2,990 satisfied customers
What do I do. The control boxes or the units at the. And the
And the two toilets both work but nothing with the electro scan… read more
Boat Doc
Boat Doc
107 satisfied customers
I have 2 Volvo penta 5.7 gxis. One of them keeps getting
I have 2 Volvo penta 5.7 gxis. One of them keeps getting water in the cylinder heads, I replaced the manifold and risers. It's still happening. The oil is clean. Can you help?… read more
Jason
Jason
Marine Mechanic
16,293 satisfied customers
Have a dragonfly 4 updated to latest now every time I turn
have a dragonfly 4 updated to latest now every time I turn it on it goes through a complete system check … read more
Matthew John
Matthew John
Cert II Electronic Engineering
41 satisfied customers
I have a 2008 Wellcraft 232 Fisherman powered with a 225 HP
I have a 2008 Wellcraft 232 Fisherman powered with a 225 HP Yamaha. Is there any reason I can't re-power with a new 300 HP Yamaha ? … read more
Jason
Jason
Marine Mechanic
16,293 satisfied customers
I own a 1965 Hatteras Motoryacht with a pair of 1965 871N
I own a 1965 Hatteras Motoryacht with a pair of 1965 871N engines. The fuel tanks are in the keel and they each have their own separate ,pick-up tubes and 1000FG racors filters, then the engine filter… read more
Boat Doc
Boat Doc
107 satisfied customers
Im getting an over heat alarm when I run on hose with muffs.
im getting an over heat alarm when I run on hose with muffs. I noticed water coming out of the peephole when the motor is not running. is that a problem?… read more
Jason
Jason
Marine Mechanic
16,293 satisfied customers
I am looking for improvements in my top end speed. I have a
I am looking for improvements in my top end speed. I have a fairly heavy bow rider. Its a 1992 Baja Islander 208 with a 350 mag. I have rebuilt the engine. It has 8.5 to 1 compression and a mild cam. … read more
MarineService8
MarineService8
34 satisfied customers
Twin 3406E 800 hp engines, under 700 original hrs Both
Twin 3406E 800 hp engines, under 700 original hrs Both produce STEAM which increases at higher rpm Clean oil analysis: no glycol..etc All gauges steady and normal Perfect performance except steam. All… read more
Cat Man
Cat Man
Vocational, Technical or Trade Scho
2,990 satisfied customers
I have a 1998 9.9 2 stroke tiller manual start mercury
I have a 1998 9.9 2 stroke tiller manual start mercury outboard. For years it gave me no problems. I pull the choke plunger out 3 times and start it right away. It runs about 30 seconds , then dies an… read more
Tan
Tan
MerCruiser Certified Technician
Certified Marine Technician
10,957 satisfied customers
Suzuki df 70 serging at 2800 RPMs. I have replaced the
I have replaced the Injector pump and spark plugs .plugs showed signs of too rich fuel .Tried it out started fine but serges At 2800rpms … read more
Jason
Jason
Marine Mechanic
16,293 satisfied customers
Bought a used 2001 Sea-Doo Challenger 189 Bombadier and took
Bought a used 2001 Sea-Doo Challenger 189 Bombadier and took it out today for the first time and the hull completely filled with water! Drain Plus were in … read more
Boat Doc
Boat Doc
107 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x