Engine Wire Harness Upgrade Questions

[Jon W]

I've received the harness upgrade Kit A with volt meter. I was looking over the engine to get an idea of how to approach making the change. I noticed a couple of things that I'd appreciate some help on. The wire harness has 9 wires. 4 are 10 AWG, and 5 are 14 AWG.

Questions -
    When I remove the orange wire from the original setup, there will only be 7 left to interconnect. What are the other two wires for?

    Per the Kit A schematic, the yellow/red wire to the engine panel push start button is 14 AWG. The wire harness sent is 10 AWG. Will
    using 10 AWG be a problem going up and down in wire size?

    The Kit A schematic has the glo plug wire as gray 10 AWG. The closest to gray in the harness sent is a white 10 AWG. Is the white
    10AWG for the glo plug?

    The orange wire from the output of the alternator to the engine panel is to be removed and attached to the positive side of the start
    motor. On my boat, the orange wire runs from the alternator separate from the plug directly to the engine control panel as 14 AWG. It
    returns in the plug to the starter as 10 AWG. Shouldn't the new orange connection from the alternator to the start motor be 10 AWG, or
    per Mainsheet should it be 6-8 AWG? Also the wires appear to connect to the start solenoid, not the start motor. Is the connection on the
    solenoid or is there a hidden connection on the actual start motor?

    The purple wire is listed as the igntion switch, but on my boat is not connected to anything on the engine or starter. It has a push on
    type connector and some electrical tape around it, but is just hanging out in the air. Looking through the head door, I can see what looks
    like a tab on the lower start motor solenoid post below where the red positive wires connect to the solenoid. Is the purple wire supposed
    to be connected on the lower post? The engine started fine the last time I started the engine. I didn't try it today. Could it have just
    fallen off today? The previous owner did replace the alternator.

Any help is appreciated.

Regards,  Jon W.

[Stu Jackson]

Harness upgrade Kit A

I've received the harness upgrade Kit A with a volt meter. I was looking over the engine to get an idea of how to approach making the change. I noticed a couple of things that I'd appreciate some help on. The wire harness has 9 wires. 4 are 10 AWG, and 5 are 14 AWG.

Jon, please see comments below.

Questions -
   

When I remove the orange wire from the original setup, there will only be 7 left to interconnect. What are the other two wires for? 

Jon, it seems you're already aware of this:

http://www.c34.org/wiki/index.php?title=File:Harness1.gif

Yes, seven wires.

   

Per the Kit A schematic, the yellow/red wire to the engine panel push start button is 14 AWG. The wire harness sent is 10 AWG. Will using 10 AWG be a problem going up and down in wire size?

Bigger is always better when it comes to wiring.  Get the connections right.  J

   

The Kit A schematic has the glow plug wire as gray 10 AWG. The closest to gray in the harness sent is a white 10 AWG. Is the white 10AWG for the glo plug?

Ron Hill has always preached: "The colors can be different."  He's right.  Just connect the wire colors, if they're off, to what they used to be before (regardless of color!).  Mine are white, but faded to close to gray, but they sure didn't start out as gray.  J  The Tech wiki has my wiring diagram, here:
http://www.c34.org/wiki/index.php?title=Faster%2C_More_Efficient_Glow_Plug_Heating_with_a_Solenoid   

   

The orange wire from the output of the alternator to the engine panel is to be removed and attached to the positive side of the start motor. On my boat, the orange wire runs from the alternator separate from the plug directly to the engine control panel as 14 AWG. It returns in the plug to the starter as 10 AWG. Shouldn't the new orange connection from the alternator to the start motor be 10 AWG, or per Mainsheet should it be 6-8 AWG? Also the wires appear to connect to the start solenoid, not the start motor. Is the connection on the solenoid or is there a hidden connection on the actual start motor?

Good question - means you are beginning to understand the link between the alternator output and the starter, starter solenoid. 

Like this:  OEM 1-2-B Switch Wiring History  http://c34.org/bbs/index.php/topic,4949.msg30101.html#msg30101

If you combine this with what Maine Sail wrote, you should be able to get closer.  Then come back with another more detailed question.

   

The purple wire is listed as the igntion switch, but on my boat is not connected to anything on the engine or starter. It has a push on type connector and some electrical tape around it, but is just hanging out in the air. Looking through the head door, I can see what looks like a tab on the lower start motor solenoid post below where the red positive wires connect to the solenoid. Is the purple wire supposed to be connected on the lower post? The engine started fine the last time I started the engine. I didn't try it today. Could it have just fallen off today? The previous owner did replace the alternator.

It could be an old alternator regulator power wire.  New alternator or new alternator AND external regulator?

Here's what I did: 

Alternator Regulator Wiring Diagrams - all three

http://c34.org/bbs/index.php/topic,4548.0.html

Great questions.

Stu

[Jon W]

Thanks Stu.
It is hard to see in there, but best I can tell the purple wire is part of the engine side harness. In your April 30 diagram I see "purple ignition to alternator". Is that what you mean by this purple wire was the connection to the old alternator? What do you mean "separate ignition to starter" in the parenthesis? Should the purple wire connect to the positive side of the starter?

Back to the orange wire - The connections I see look to connect to the start motor solenoid not the start motor. From memory 2 red wires and a yellow with an in-line fuse in a fuse holder. Taking the Kit A directions verbatim, I would remove these wires, install the orange 8 AWG from the Alternator output, re-connect the red and yellow on top of the orange and tighten the nut? Correct?

I appreciate your patience in my rookie season. I'm just learning to crawl when it comes to electrical systems. I need to go slow and connect the harness first to remove the trailer plugs and have a safe boat.

Thanks for the help.  Jon W.

[Jon W]

Professor Stu,
I followed the links and came across the attached picture from a Mainsail write up on the subject. I went to the boat this morning and started her up. No problems. Shut her down, and looked through the door in the head to get a closer look at what I have.

Turns out the new 105 Amp alternator is connected from its' output to the start solenoid just like the attached picture except the wire/cable is looped down not up. However the orange 10 AWG from the engine side harness is also attached to the start solenoid. I'm guessing when I do the harness upgrade I should remove the orange 10AWG from the start motor, correct?

The other orange 14 AWG wire from the alternator that bypasses the trailer plug I mentioned in previous post, may be direct connected to the engine control panel as the replacement for the yellow and purple wire in the attached picture. My purple wire is there, but not connected to anything. I won't know until I remove the engine control panel and look.

Thanks for the guidance. Jon W.

[Stu Jackson]

Jon, I wrote these up before I saw your last post.  My answers include a link to that very article with that picture.  I'll post this, and then review your new questions after lunch.  

Thanks Stu.
It is hard to see in there, but best I can tell the purple wire is part of the engine side harness. In your April 30 diagram I see "purple ignition to alternator". Is that what you mean by this purple wire was the connection to the old alternator? What do you mean "separate ignition to starter" in the parenthesis? Should the purple wire connect to the positive side of the starter?

Jon,

The PURPOSE of me posting those diagrams was to show what was on MY boat, so I could: 1) keep track of what I was doing while I was working on it and record what I had done; 2) provide an EXAMPLE of how to make wiring sketches for others.  It was NEVER intended to be a "here's what you should have on your boat, too" example, although if the wiring colors were the same, it would be, or close, right?

Please also remember that those sketches were prepared when I was doing a number of things at the same time:  1) removing the old OEM Motorola alternator; 2) decommissioning and later removing an old Auto Mac regulator; 3) installing a new 100A alternator; 4) installing a new Balmar MC-612 external regulator.  

Because it appears you're only doing the wiring harness upgrade, your issues will be somewhat different, because you're simply trying to match like-for-like.  In my case, I had to not only figure out what was there, but I had to learn how to hook the new stuff up.  I "borrowed" much of the second two wiring diagram sketch layouts from that wiring harness diagram in the Tech wiki.

That said:

I see "purple ignition to alternator". Is that what you mean by this purple wire was the connection to the old alternator?  

If you follow the three sketches, you'll see that the purple wire is from the cockpit panel ignition switch to the old alternator's REGULATOR.  This is the "signal" that turns the regulator, whether internal or external, ON when the key switch is turned on.  On my boat, that wire was purple from the cockpit panel, went to a quick connect electrical connection into a brown wire, which then went to the ignition input of the new regulator (brown).  In addition to identifying the color of the wires, keep working on learning the PURPOSE of each wire, too.

What do you mean "separate ignition to starter" in the parenthesis? Should the purple wire connect to the positive side of the starter?

No.  What that means is clarified by the upper right note on the second sketch: "Note: starter is not involved in the new alternator wiring..."  Then check the third sketch to see #5 red to starter solenoid.

The only way I was able to see all this stuff was to DROP the alternator.  Since I was taking it out anyway, it didn't matter to me.  In your case, it wouldn't hurt, since it would help to identify the wires on the back of the alternator, as well as more importantly for your EXPOSE the wiring to the starter and starter solenoid.  Once you do, you'll have an "AHA!" moment.

Maine Sail did an excellent writeup (it's different than what you're doing) but has very good pictures and descriptions, especially "Bypass the Orange/Red Circuit", the one with "the Quick & Dirty Fix box," here:  http://www.pbase.com/mainecruising/catalina_36_alternator  I'm not suggesting you do what this article describes, just trying to give you more information, for the  next question below.

Remember from above, I said:  "If you follow the three sketches, you'll see that the purple wire is from the cockpit panel ignition switch to the old alternator's REGULATOR."  Since you're keeping your old alternator, that wire should still go there.  It energizes the regulator when the key switch is turned on, and the regulator is what makes the alternator produce current.

Back to the orange wire - The connections I see look to connect to the start motor solenoid not the start motor. From memory 2 red wires and a yellow with an in-line fuse in a fuse holder. Taking the Kit A directions verbatim, I would remove these wires, install the orange 8 AWG from the Alternator output, re-connect the red and yellow on top of the orange and tighten the nut? Correct?

That orange wire has been the BIG question for most skippers for the past 30 years!!!  You are NOT alone!  The Maine Sail article also explains it.  My third sketch shows this.  The starter is on the bottom of the sketch; the starter solenoid is just above it, with the yellow wire going to the starter solenoid from the start button via the harness.  Since I was replacing my alternator and installing a new regulator, I didn't have the answer to this question.  I point you back to the "OEM 1-2-B Switch Wiring History" link from my last reply.  Your goal should be to understand what's happening there at the starter and starter solenoid.  Once you do, you can determine what wires to connect properly.

I appreciate your patience in my rookie season. I'm just learning to crawl when it comes to electrical systems. I need to go slow and connect the harness first to remove the trailer plugs and have a safe boat.

That is a worthy goal.  You'll get there.  Remember, none of was born an electrician.  I spent, literally, years drawing sketches on notepaper while I was eating dinner alone on business trips to get my head around this stuff.  We've tried to capture as much as we could for skippers like you, so you could avoid reinventing the wheel.  My wheel, in this particular case, was a tad squarer than yours!

[Ron Hill]

Jon W : You probably haven't seen my posts on not needing the wiring harness "euro" connectors, but here's an idea:

I had to remove and reinstall my old engine from the boat (over 5000 hr on it) 2 different times to fix oil seal leaks.  Then I had another problem with it and decided to just install a new engine.
On all of those times I disconnected the wires at the engine  I didn't touch the connectors at the engine or the engine instrument panel!!!!

The wiring harness was installed at the factory for ease of production and if you ever have to remove your engine (I hope not) you'll disconnect the wires at the engine not at those connectors as it's easier!!  I've never had to disconnect the wires at the engine instrument panel and can't conceive of a reason that anyone would ever have to!!!

I'd cut a wire from the 'trailer plug" and then cut the matting wire and connect those two wires together.  You can use a butt splice or solder them with a heat shrink sleeve.

Anyway think about it and save yourself a bunch of unnecessary work.  Good luck

A few thoughts

[Stu Jackson]

Professor Stu,
I followed the links and came across the attached picture from a Mainsail write up on the subject. I went to the boat this morning and started her up. No problems. Shut her down, and looked through the door in the head to get a closer look at what I have.

That look and Maine Sail's pictures should help you a lot.  If you go back to my three wiring diagrams, the third one showed the starter and starter solenoid.  Based on your visuals and Maine Sail's pictures, the BIG red wire from the C post of the 1-2-B switch lands on the BIG post of the starter solenoid, and just inboard (behind) that big lug is the slip on connector of the yellow/red stripe wire from the start button, the one with the notorious fuseholder (please also see the Critical Upgrades about that while you're in there).

Turns out the new 105 Amp alternator is connected from its' output to the start solenoid just like the attached picture except the wire/cable is looped down not up. However the orange 10 AWG from the engine side harness is also attached to the start solenoid. I'm guessing when I do the harness upgrade I should remove the orange 10AWG from the start motor, correct?

What you need to begin to do is start writing and thinking about the FUNCTION of the wire, not just the size and color.  In fact, size & color alone tell you nothing.  You NEED to know what that wire did or used to do before you disconnect anything.

You HAVE TO begin to ask yourself this:  "What does this wire do?  What is this wire called?"  Only then can/should you can identify it further by size & color.

I know, this doesn't answer your question, but you need to answer it.  Please see my previous post about why I'm not answering it – my stuff was different, I didn't do what you are trying to do.

The other orange 14 AWG wire from the alternator that bypasses the trailer plug I mentioned in previous post, may be direct connected to the engine control panel as the replacement for the yellow and purple wire in the attached picture. My purple wire is there, but not connected to anything. I won't know until I remove the engine control panel and look.

See above.

In addition, this is an excerpt from the OEM History link:  


"...one wire with a little connector between the alternator output and the starter (Fig. 2)  Why?  It was cheaper to build.  That one big wire served two purposes:  when starting it took power from the (selected) battery-or (ies) and fed it TO the starter, and through the small wire between the AO and the starter (small wire, short distance, high current, short time period of current flow); once the engine was running, the small wire did nothing, but the AO started flowing current BACK from the alternator to the switch in the opposite direction.  Same wire, current flowed in a different direction."

That small wire between the AO and the starter is CRITICAL to understanding what is there.

Also, here is a quote from Maine Sail's article that you found and read.  The critical part of understanding what's happening is explained.  That new red wire jumper is the key.  What Maine Sail did was to REPLACE the short small wire between the AO output and the starter with a heavy gauge red wire.  Better solution with heavier wire for the heavier load, same FUNCTION.  

Here's the quick and dirty fix. Try to focus on the red wire between the back of the alternator and the starter post. Simply jump the alternator output to the starter post and disconnect the orange wire. With this jumper the alternator output bypasses the 20+/- feet of teeny tiny 10GA wire and uses the large gauge starter wire to make its way back to the battery switch and then to the battery banks. Minimal voltage drop compared to the 10GA circuit and much less resistance and heat without going through all that small wire and two trailer connectors.

Think of it this way:  Any wire has two ends.  If it goes from the starter to the AO, it's the same as going from the AO to the starter.   Go back to the OEM history again, and reread it a few times.

Good luck.  Keep 'em coming.

PS - Ron's advice is superb.  Save some work.

[Clay Greene]

Amen to Ron's advice.  The termstrip is an improvement on the trailer plugs but unnecessary.  Make it fool-proof and connect the wires together. 

[KWKloeber]

Jon,

Do yourself a huge favor, and replace the wires all the way back to their termination at each engine component. 

The problem is (sometimes, but) rarely the section of the harness between the gummy bear plug to the cockpit.   The most problems are the sections between the gummy bear plugs and the engine terminations.  I won't get on my soapbox here about the stupidity of the CD / Seaward harness "upgrade" -- it's been well covered herein before.  Just understand that it isn't a panacea, and after you are done, the upgrade is still not ABYC compliant and leaves your entire harness unprotected from over current that might occur due to a short, and so therefore remains a fire hazard.

Remove the fuse at the starter solenoid - it's useless and is at the wrong end of the harness.   
One tip - the 1/4" quick connect to the solenoid is problematic and subject to corrosion and loosening.   Solder a wire w/ a female to the solenoid tab - cover the whole connection with HST.  6" away, put another male/female quick connect that's moisture-proof.

If you ever need to replace the solenoid I have one that replaces the OEM,, but has a threaded post for a ring terminal instead of a slide-on quick connect.

Heed Stu's advice about learning/understanding the purpose of each circuit.

Ken

[Jon W]

Hi Ron, I have read your post(s) and will not be using the euro connectors. Ken, I will replace the engine wires back to their engine termination point with new, and try to solder an extension to the quick connect on the solenoid. The orange wire will be discarded. Saturday I will be taking the aft cabin apart to check if a strainer is in the diesel fuel line inside the tank. Removing the cabin bulkheads will let me see if the new 16 ft harness will reach from cockpit panel to the engine connections with slack for removal/maintenance. If not I'll need to add wire and butt splices at the engine end of the harness. If luck is on my side, I won't need any splices except for the fuse.

The fuse however seems to be all over the map. Use 20 amp, use 30 amp, don't do it, use ATC type, add a second fuse to the red wire (which is also in the engine manual schematic). Adding the 20 Amp ATC type for the reasons Mainsail points out, and moved away from the engine as Stu and others have done might be the way I make the upgrade. Not sure yet about the additional 30 Amp on the red wire. Still a couple of weeks to decide, but then all critical upgrades listed on this site will be complete. Other improvements and learning will continue.

Thanks to all for the great advice and guidance.  Jon W

[Stu Jackson]

1.   Removing the cabin bulkheads will let me see if the new 16 ft harness will reach from cockpit panel to the engine connections with slack for removal/maintenance. If not I'll need to add wire and butt splices at the engine end of the harness. If luck is on my side, I won't need any splices except for the fuse.

2.   The fuse however seems to be all over the map. Use 20 amp, use 30 amp, don't do it, use ATC type, add a second fuse to the red wire (which is also in the engine manual schematic). Adding the 20 Amp ATC type for the reasons Mainsail points out, and moved away from the engine as Stu and others have done might be the way I make the upgrade.

Good to hear, Jon.

1.  That 16 foot harness (i.e., wire only) was "designed" to reach from a Euro strip in the cockpit to a Euro strip in the engine compartment, not all the way to all the connections on the engine.  On my boat, the engine Euro strip is located pretty much at the aft portside engine mount.  So, as a guide, you should realize that the new wires, first, won't reach "all the way" to each component on the engine, and, second, you'll be doing a LOT of butt splices.  I mention this only to avoid any assumptions on your part as to how far the wires will reach.  In fact, Seaward at one point offered a longer 18 foot harness, but since you have the 16 foot one already...  ITWMB, I'd connect the new wires to the instruments in the cockpit panel first, then snake the wires down to the engine area, and find a "comfortable" place to do the butt connections.  This could well be from the aft compartment "hole" or from above with the engine covers off.  Your boat, your back!     Only seven wires, right?     While you're at it, instead of doing two butt connections for each wire, replace the wires that now connect to the engine with new longer wires that reach back to wherever the new harness wires end.

2.  Ken's advice in Critical Upgrades is that the fuse between the start button and the starter solenoid is useless in that circuit, regardless of how "clever" I might have been in relocating it.  While I haven't personally researched it myself, and have chosen to leave it in knowing it's a 'weak link' but at least very accessible, I would urge you to follow Ken's suggestions to deal with fusing the main lead to the cockpit panel.  IIRC, that's his point.

Good luck, glad we could help.

[britinusa]

Sorry guys, having difficulty understanding what you are talking about when it comes to gummy bears, termsticks, etc.

Here's a pic showing some do-hickies in my boats wiring harness.

Any chance you guys can post pics showing a harness gummy bear, termstrip etc look like?

Thanks.

Paul

[Jon W]

Stu, poor wording on my part. I meant to say if the harness would not reach from cockpit panel to engine terminations with slack for maintenance/serviceability, I would connect directly to the cockpit panel and add the splices only at the engine end so they are accessible. I intend to have as few splices as possible. I'm going to take the wire to a local electrical supply to see if they carry this type wire or equivalent. Looking online THHN/THWN has less strands, but the exact same specifications as AWM otherwise. It even references THHN/THWN used as AWM.

I ran across the acronym RTFM, but what does ITWMB mean? If iT Was My Boat?

By main lead you mean the red wire from starter solenoid to the "B" side of the ignition switch (when VM installed). I believe this is the one Mainsail added a 30 amp inline fuse to.

Paul,
I don't have any pictures to post, but gummy bears refers to the trailer type electrical connections where the engine wires and extension wires (harness) join. They are also behind the engine control panel in the cockpit joining that end to the harness. The harness is simply 9 individual wires (5 14AWG and 4 10AWG) taped together and solder tinned at each end. Not really a harness in my opinion. Termsticks I think was meant to be terminal strips or euro strips which come with the harness upgrade kit to replace the plugs/ gummy bears.

Jon W.

[Stu Jackson]

Sorry guys, having difficulty understanding what you are talking about when it comes to gummy bears, termsticks, etc.

Here's a pic showing some do-hickies in my boats wiring harness.

Any chance you guys can post pics showing a harness gummy bear, termstrip etc look like?

Paul,

Your picture appears to show what are waterproof fuseholders, those yellow thingies.

To answer your other question, please read the Critical Upgrades topic, which has tons of posts about the wiring harness plugs, aka, gummy bears.  There are links to many other threads with pictures.

Critical Upgrades  http://c34.org/bbs/index.php/topic,5078.0.html

The term strips (Euro strips) are shown in the original wiring harness article located in the Tech wiki under engines:  http://www.c34.org/wiki/index.php?title=Engine_Harness_Upgrade

[Stu Jackson]

Stu, poor wording on my part. I meant to say if the harness would not reach from cockpit panel to engine terminations with slack for maintenance/serviceability, I would connect directly to the cockpit panel and add the splices only at the engine end so they are accessible. I intend to have as few splices as possible. I'm going to take the wire to a local electrical supply to see if they carry this type wire or equivalent. Looking online THHN/THWN has less strands, but the exact same specifications as AWM otherwise. It even references THHN/THWN used as AWM.

I ran across the acronym RTFM, but what does ITWMB mean? If iT Was My Boat?

By main lead you mean the red wire from starter solenoid to the "B" side of the ignition switch (when VM installed). I believe this is the one Mainsail added a 30 amp inline fuse to.

Jon,

If you want to minimize butts, you will have to make ONLY one butt connection on each wire:  where the wire harness wiring ends at the engine end and the new wires from the engine connections themselves.  That's it, 7.  However, remember that when you make up the new wires that connect to the engine, you're going to be making new connections there, too, like to the thermostat and oil pressure sensor new ring terminals, etc.   So, 14.  Each butt has two crimps, so 21.

Do you have a ratcheting crimper?  If not, get one.  It's a wonderful investment.

ITWMB mean? If iT Was My Boat?  If That Was My Boat.  Close!  Good for you.    [I did make that one up myself.]

Don't overthink the wiring.  You can buy Anchor wire at WM, figure the lengths and buy the right colors and gauges.

Main lead:  see my last post, I dunno specifically, Ken does.