Need suggestions / electrical help

[keysguy]

Good Afternoon Everyone,
I have a '87 Aquasport 250XF that I am working on, some of the gauges and switches do not work and I am looking to fix/replace them.  In particular the trim tab single lever switch for bennett tabs is no longer in production.  There are alot of wires that are in bundles but not connected to anything.. Can you all take a look at the following pictures and give me some suggestions or help on where to start?


Imgur album link: http://imgur.com/a/ODUDp

Thanks,
Alex

[Georgie]

Hi Alex,

I hate to say it, but you've got some work to do before you'll know what needs to be replaced and what just needs overhaul.

Heres a link that will give you color codes for your engine harness http://www.classicaquasport.com/phpbb3/viewtopic.php?f=8&t=3562...and here's another link from Scott's (aka Circle Hooked) site that will give you boat accessory wiring harness colors  http://theaquasportboatclub.com/viewtopic.php?p=5067

The group of brown and tan wires that are all severed concern me.  They usually control the warning horn and overheat alarm circuit (among other things).  Does your alarm horn work?  There are also several loose hot wires visible too...  

You need to get rid of the small glass fuse block and upgrade with some newer blade fuses.  Blue Seas makes a popular one, and Seabob recommends Genuinedealz.com as one of the betterr/cheaper vendors.

Do you know how to test your wires for continuity?  You may need to trace a lot of wires in your bundles in order to verify they carry the current properly.  If they're intact, then at least you know either your switch or your device are the problem.  You can also use the continuity test to check the Bennett switch (as well as other switches) and see if it's still sending the current as intended to the solenoid or pump to operate the trim cylinder.  Also, really curious what the dead-end yellow wire is coming from your rigging tube?  

Depending on $$ you probably will want to replace as many of your conventional connectors with heat shrink connectors as possible.  

I know this is a fairly generic post, but ya gotta start somewhere, right?  

[keysguy]

Thanks Georgie!
Currently the boat does not have any signals or alarms when the ignition is turned on.  I inherited the boat and the last overhaul of it was in 2003.  To be honest there are a ton of loose wires there.  I have a voltage meter, is that what you mean by checking for current?  I have very limited wiring experience, but can figure out how to crimp wires and heat shrink them.. :P

The yellow wire is next to starboard battery which is in a compartment where you see the rigging hole. It goes into the hull. So I'm at a loss too.

There is also a "Newmar power line noise filter" attached above the glass fuse block, is that a necessary still?  Also, I have no idea what the correct amps are for each fuse since I don't have a manual for the boat.. any suggestions there?

Also the boat was originally outfitted with OMC Johnson motors, do you think that the wiring could I should follow is that? Have they changed in 26 years?

Hi Alex,

I hate to say it, but you've got some work to do before you'll know what needs to be replaced and what just needs overhaul.

Heres a link that will give you color codes for your engine harness http://www.classicaquasport.com/phpbb3/viewtopic.php?f=8&t=3562...and here's another link from Scott's (aka Circle Hooked) site that will give you boat accessory wiring harness colors  http://theaquasportboatclub.com/viewtopic.php?p=5067

The group of brown and tan wires that are all severed concern me.  They usually control the warning horn and overheat alarm circuit (among other things).  Does your alarm horn work?  There are also several loose hot wires visible too...  

You need to get rid of the small glass fuse block and upgrade with some newer blade fuses.  Blue Seas makes a popular one, and Seabob recommends Genuinedealz.com as one of the betterr/cheaper vendors.

Do you know how to test your wires for continuity?  You may need to trace a lot of wires in your bundles in order to verify they carry the current properly.  If they're intact, then at least you know either your switch or your device are the problem.  You can also use the continuity test to check the Bennett switch (as well as other switches) and see if it's still sending the current as intended to the solenoid or pump to operate the trim cylinder.  Also, really curious what the dead-end yellow wire is coming from your rigging tube?  

Depending on $$ you probably will want to replace as many of your conventional connectors with heat shrink connectors as possible.  

I know this is a fairly generic post, but ya gotta start somewhere, right?  

[Georgie]

Also the boat was originally outfitted with OMC Johnson motors

Herein lies an additional issue.  With no idea who refit the boat with your merc's, we've NO idea what was done.  I know 1979-1996 OMC harnesses fairly well, and Fitz knows Mercs really well, but we'd both probably need to see how the engine wiring harness was adapted to fit your Mercs as I'm not getting the impression that all the wiring was replaced; of course, I could be ignorant and not recognize a merc harness stacked on top of some residual OMC wiring.  Can you get some photos of the harness to engine connections?  If stock Merc wiring wasn't used to connect the engines to the console, then I'd probably feel inclined to trace EVERYTHING and write a bunch of notes and add tags/labels so I know exactly what everything does, but an OMC wire color chart will help.   You'll also want to trace the loose red wires for sure.

I have a voltage meter, is that what you mean by checking for current?

Yes, but not all voltage meters have continuity setting...and you want one that makes an audible beep if it finds a closed circuit.  

As a disclaimer, all my wiring knowledge comes from refitting and rewiring my own boats.  I've learned as I go, read what I could, and have never done it professionally...and I recently sought help here for a symptom that turned out to be a no more than simple ground issue.     How embarrassing.

I have no idea what the correct amps are for each fuse since I don't have a manual for the boat

Fuse amperage is determined by the maximum draw of the accessories you wire to each circuit...it can be looked up even if you don't have a manual.  You DON'T want to oversize the fuze or you waste its ability to protect the device.  Typically bilge pumps and similar high-draw motors (washdown pumps, horns, etc.) require slightly larger fuses (i.e 2000 gph Rule pump needs a 15 amp fuse), nav and courtesy lights require mid-size fuses (general rule of thumb approx 1 amp per incandescent bulb - LED's are less), and electronics often require the smallest to make sure they're adequately protected (my eagle fishfinder/GPS requires a 3.5 amp fuse).

I'd also HIGHLY recommend getting your alarm circuit functioning before taking another trip.

...and by all means listen to what Seabob says if his comments contradict mine...it's his training AND livelihood.  I only stay at a Holiday Inn Express from time to time...

[Georgie]

oh...and I have NO idea about the Newmar Power noise filter thingy...   It's an audio add-on, but that's all I got.

[seabob4]

Alex,
I did look at your pics yesterday, just didn't feel like typing out a long and winded response...football, y'know!

Anyway, my thoughts.  You have quite a tangled mess of spaghetti on your hands.  VERY difficult to determine what is what, what loose wire goes where, if indeed that loose wire is necessary at all, that sort of thing.  You can sit there and stare at it for hours, try to follow things visually, try to unravel this or that, but in the end, that pretty much gets you nowhere.  Been there, done that, so to speak...

Now, understand I do this sort of thing for a living, and I've been doing it a long time, so take this understanding my level of comfort doing what I'm going to suggest here.  When I get a boat in the condition yours is in, I unplug EVERYTHING!!  You need to get all that chit out of the way so your mind can process what your eyes are looking at.  Every boat consists of 2 separate electrical systems.  The “boat's” system and the “engine's” system.  The boat's system is every electrical device on board unrelated to the engine.  The engine's system is, of course, everything engine related, trim, gauges, that sort of thing.  By getting everything unplugged and out of the way, then you can attack each system separately without having the other system “confuse” you as to just what you are looking at.

Typically, a boat's electrical components are all wired into what we call the hull harness, or main accessory harness.  These wires culminate into a plug, which is plugged into a mating connector coming off your switch panel.  The ground wires for all the equipment may or may not terminate into another plug that comes off your ground bus bar.  Seeing the age of your boat, what's been added in or changed over the years, the re-rigging, some of the original stuff may not be there any more.  But this is the basis as to how things work electrically.  

In regards to equipment functioning, once you have all the engine crap out of the way, you can more easily trace the leads coming of the switches, determining what wire powers what item, and start checking for voltages and continuity.  For instance, I believe you said your nav lights don't work.  Once you determine the lead that powers the nav lights (gray or gray with a colored stripe), you can check for voltage at the switch, voltage in and out of the plug, and continuity between the plug and the nav light itself.  Depending on what you find (voltage or no voltage, continuity or no continuity), you can isolate the problem to either the switch, the fuse, the wiring, or the nav light itself.  Anything else that doesn't work, you follow the same steps.

In regards to the engine harnessing, I seriously doubt the old OMC harnesses were “adapted” to run the Mercs.  Way to much work to do that.  Once you get everything unplugged, you'll find out just what you have for engine harnesses.  On Merc harnesses, at the helm end, you'll have a 3-wire plug coming off each harness running to the binnacle (shifter) for trim and tilt (we call it TNT).  For the gauges, you'll have short leads, purple, black, tan, brown w/white stripe, and gray.  At the engine end, on the starboard side of the powerheads, there will be a large, round black connector.  Verify you have these features and you have Merc harnesses.  Anything else that's just laying there like it may be the remnants of old OMC harnesses should be yanked out.

Regarding the trim tab switch, I haven't seen that old joystick switch in years.  The problem may be in the switch, it may be in the harness connecting it to the pump, without troubleshooting, very hard to tell.  One thing I WOULD do is make sure you have a good ground on the pump.  Remove the plastic cover, you'll see the ground wire on the back side of the pump body.  Check for continuity between that and a known good ground.

Hope this has helped some.  It's a bit daunting to a novice, but with a little patience an d planning (and understanding of how things work), it's very doable...