weird power issue?

[stubbsboogie]

OK so this has happened twice in about a month. For some reason I loose all power on my dash, well not all, just the guages. The backlights behind the guages work. My trim goes out at this time too. Nothing no up or down. I can shut it down for a little bit and it has come back on. I have checked all fuses, looked at wiring as close as I can. Not really sure where to even look for more causes.

I am concerned thatone day it may go out and not come back on, which would make it impossible to get on to the trailer. what do I do? Wait till it fails or take it in and have someone possiblly chasing a ghost.

Any info or opinions would be greatly appreciated, thanks.

 

[Macwrench]

Re: weird power issue?

I would start troubleshooting cheap first. Maybe they all have a common ground. Even though it may look ok, it could have corrosion or a bad crimp. Start there. If you're in Florida, then you have the same corrosion problems we do in Texas. We call it the "Galveston Galvanize" and it can ruin your day.

 

[DaNinja]

Re: weird power issue?

I would start troubleshooting cheap first. Maybe they all have a common ground. Even though it may look ok, it could have corrosion or a bad crimp. Start there. If you're in Florida, then you have the same corrosion problems we do in Texas. We call it the "Galveston Galvanize" and it can ruin your day.

I was thinking a common ground problem, as well. That's about all I think they could share (without a schematic in front of me).

 

[Bob's Garage]

Re: weird power issue?

This is just a guess as I am not familiar with either of your boats.

I think that the gauge lights have a separate ground from the gauges and t/t. Look for a 'buss bar" where the involved wiring circuits are grounded.

Don't just look, give each a slight tug and wiggle. Also check the condition of the main negative wires as corrosion can creep up inside the cables.

If everything checks out, I would next look at the ignition switch. It may have a separate connector for the lights and gauges.

 

[bear_69cuda]

Re: weird power issue?

Also,
Check or follow the positive leads to the fuse or circuit breaker, sometimes wire terminal female spades connector can come off the male end, or be loose... Same with negative ground...

 

[rwidman]

Re: weird power issue?

OK so this has happened twice in about a month. For some reason I loose all power on my dash, well not all, just the guages. The backlights behind the guages work. My trim goes out at this time too. Nothing no up or down. I can shut it down for a little bit and it has come back on. I have checked all fuses, looked at wiring as close as I can. Not really sure where to even look for more causes.

I am concerned thatone day it may go out and not come back on, which would make it impossible to get on to the trailer. what do I do? Wait till it fails or take it in and have someone possiblly chasing a ghost.

Any info or opinions would be greatly appreciated, thanks.

One of the boats in your signature? Which one?

 

[stubbsboogie]

Re: weird power issue?

One of the boats in your signature? Which one?

Thanks for the help. That is the question is the rinker. I will start checking ground this weekend. Yeah hopefully that is what it is.

 

[rwidman]

Re: weird power issue?

Thanks for the help. That is the question is the rinker. I will start checking ground this weekend. Yeah hopefully that is what it is.

I had the very same problem on a Volvo I/O. There is a wiring harness on the engine and it has a plug and socket where it connects to the boat's wiring. On the Volvo, it was at the rear of the engine on the starboard side near the top of the engine. It may be in a different place on yours.

The plug and socket were covered with a rubber boot and secured with a hose clamp.

On mine, removing the hose clamp and boot, then unplugging the harness, cleaning the contacts with electrical grade contact cleaner, and reassembling cured the problem.

Unplug the plug, spray the pins and sockets, reinsert the plug, remove and and repeat a few times. Now, put a light coating of dielectric grease on the pins and the face of the socket and reassemble one more time. Install the boot and clamp.

The gauge lights still work because they are on a seperate circuit. The gauges and trim are powered through the engine harness.

Of course, it could be something else. It's hard to diagnose these things over the Internet.

 

[nlain]

Re: weird power issue?

If you don't already have one get a Mercruiser service manual that covers the engine and drive, in the back is a wiring diagram that covers most of the wiring in your boat since most of it is connected to the engine and drive. It will be a big help.

 

[Silvertip]

Re: weird power issue?

The reason the dash lights remain on but the gauges quit is because there are two electrical systems on a boat. The engine harness powers the gauges but the "boat" harness powers the lights. Therefore look at the engine harness connections at the engine. The engine harness also interfaces with the trim system. A "common ground" is not the problem as the two systems have separate grounds. If you don't know what the two systems look like, the smaller cables attached to the battery are the "boat harness" which feeds the fuse panel and then the accessories. The engine harness feeds the gauges themselves, the trim system, and starting system.