Wire Harness connector

[Bolo]

Our E-32 III has a M-25XP on board and I recently had to have the transmission rebuilt. That's another story I'll post here after getting the bill from the yard. (It wasn't a happy experience.) After the work was done I went onboard to check the work and take the boat out for a spin. But as soon as I started the engine I noticed that all the instruments on the panel were dead. The engine and even the blower worked fine but the tach, water temp and battery charge were not working. I was also winterizing the boat and went on to that work before going back to my hotel. (we live about an hour and forty minutes from the marina.) That night I remembered that I had a similar problem with the wiring harness connector at the engine long ago. Sure enough, the next morning I started the engine and had the first mate look at the instruments while I "played" with the connector and they came to life.

Now I did pull it apart and put it back together a few times but it seemed that when I moved the wires around and the connection joint the instruments would sometimes die. This is what probably happened when the technicians worked on the transmission. So...I'm think that the pins in the connector could be pitted (and they did look sort of like that a bit) and/or the connector itself is failing. It's looks like an old design, sort of rubbery beige. So, I was thinking that I should consider replacing this connector with a new one but I also noticed that the wires seem to be molded into the body of the connector. Has anyone every replaced this part and if so then where did you get the replacement? I'd imagine that I would need to take careful notes as to what wire connects with what other wire before I cut anything and re-wire through a new connector.

 

[Bolo]

A photo

OK, this is not exactly the way the harness looks because of it's color but the design is very similar. It looks to be a 8 pin trailer connector??

 

[Loren Beach]

OK, this is not exactly the way the harness looks because of it's color but the design is very similar. It looks to be a 8 pin trailer connector??View attachment 17341

Bob, The problem is age... I doubt that anyone really considered whether this style of connector would be working well this many decades into the future!

Our M25XP has a couple of these connectors, put there in that harness by Universal to enable the OEM to put it all together quickly in a production line. We have one inside the engine compartment covered by a LOT of tape. Another tucked up underneath the cockpit panel - more covering tape.

I believe that the best solution for the long haul would be to source lengths of wire -- up-sizing gauge where appropriate! -- AND those wires would have to be correctly color coded. Then replace that old run with its dying connectors with uninterrupted wiring, and put it inside some flex conduit while I was at it.

I have not done this project, but did have to bypass the supply wire for the 12 volt feed for the fuel pump when the original wire dropped to about 10 volts. (That fuel pump wire also powers the engine hour counter on our boat model, and also the ready light for the Halon extinguisher.)

Regards,
Loren

 

[Christian Williams]

That is the infamous "trailer connector". There are two, one near the engine and one at the other end, near the cockpit gauges.

They keep Internet Guru Maine Sail (R.C. Collins) up at night: http://www.pbase.com/mainecruising/universal_wiring_harness_upgrade

But if your boat is like mine, it may be that many wire connections in the harness are loose or corroded, and the grounds compromised by lack of attention. It's inevitable in an aging boat.

I tackled all that with some success and came away considerably wised-up, a couple hundred bucks poorer, and much more confident about engine matters in general:

http://www.ericsonyachts.org/infoex...ng-Upgrade-Part-2-Alternator-Jump-and-Bus-Bar

See also Part 1:

http://www.ericsonyachts.org/infoex...5-Engine-Wiring-Upgrade-Part-1-Cockpit-Gauges

 

[woolamaloo]

I replaced mine last winter...

The dreaded trailer plugs. Mine looked a little melted and were causing shorts. Every turn of the key was a crap-shoot. They weren't as bad as the plugs on the page Christian mentioned but they made me uneasy nonetheless. I'd go below and fiddle with them until the engine would start. Luckily, that always happened at the dock but it was no way to live. I decided to (pay my mechanic to) replace them along with all the wiring with bus bars for the engine as well as upgrade the engine panel and rebuild my alternator and starter motor. I'm hoping for another 30 years. I'm much happier with it - and the pain in my checkbook has mostly been forgotten.

Jim
Woolamaloo
1985 E30+ Hull #685

 

[Tom Metzger]

If I was in salt water I would get a bunch of butt connectors and replace the trailer connectors with crimps.

If you want to get fancy you could replace the trailer connectors with another type connector, but there is no good reason why you would want to disconnect them. You might also have a problem finding suitable connectors that you can hook up. Some people have installed terminal strips, but I don't see the point.

For crimps, you would need 4 yellow #10-12 crimps and 5 blue #14-16 crimps for each of the two connectors. The wires are color coded so it is an easy job.

 

[frick]

Molex Plug

My Yanmar uses a few white molex Plugs. Here is an important trick that will stop the rust and corrosion in the plug. Use Dialectic Grease which will stop the air and water infiltration. WD40 works too... The WD stands for Water Displacement!

Rick+

 

[supersailor]

Electrical Plugs

After a disastrous season with the engine failing three times, I threw away the engine electrical "system" and started over. The failures all occurred in the first season I owned the boat and none of them in a good spot. The first was in the Port Townsend Cut. The second in the Agate Passage with the tide running four knots and the third time in the Straights of Juan de Fuca outside of Port Angeles with zero wind. Actually all three times were with zero wind out. I don't know if any one else's M25XP is malicious as mine but mine only quit at the worst possible times. Flushing through the Cut and the Passage with no power of any kind was not fun.

Using trailer type connectors in a salt water environment is not wise. They aren't great in fresh water either. Ask any trailer sailor. Anyone that still has them really needs to replace them unless they like to be stranded. I used a Blue Seas terminal strip above the engine for all the hots and a second one to collect all the grounds. This replaced the "system" of grounds all over the engine with a single large ground and all other connections up high. The instrument panel side terminates at a Blue Seas fuse block with cover in the cockpit locker next to the instrument panel that terminates the grounds also. The fuse box at the instrument panel allows me to troubleshoot while single handing. The terminal blocks allow solid wire connections and the disconnecting of any wire without disturbing the harness. Liberal use of dielectric grease doesn't hurt either. While redoing the electricals, I corrected what I consider a few other flaws. The glow plugs are run through the ignition switch and then through the glow plug push button then through the ignition system. All of this is first fed through the ammeter. This creates a long high current flow from the engine to the instrument panel and back to the engine again with substantial voltage loss on the way. In fact, one of the engine failures happened because the push button switch at the panel for the glow plugs failed by welding the contact in the on position leaving the glow plugs on 24/7. The fuel pump failed due to low voltage (10.7 volts). I wanted to add a Bosh relay so that the high current had a 3' run from the battery to the glow plugs instead of the approximately 20' round trip before. The result is a 10 second start when it is 28 degrees out. The second thing I wanted to do was separate the glow plugs from the starting circuit. The M25XP only needs the glow plugs when stone cold. The rest of the time it doesn't start any faster when the plugs are on. There is no reason to heat everything up every time you start the engine. The third thing I wanted to do was exchange the ammeter for a voltmeter. I couldn't see what good the ammeter was doing me in the cockpit. A volt meter would tell me immediately that the alternator is working and approximately the amount of charge the batteries were accepting. If I needed more, my power monitor at the nav station could tell me more than I needed.

The rewire was a good winter project that has now given me a totally reliable engine that I can rely on for the foreseeable future. If anything gets "screwed up" in the future, I know who did it and how he did it.

 

[Christian Williams]

Excellent work. For anyone contemplating, the entire PhD in DIY is contained in threse links:

http://www.ericsonyachts.org/infoexc...3793#post83793
http://forums.catalina.sailboatowner...d.php?t=135558
http://c34.org/bbs/index.php/topic,5078.0.html

 

[Bolo]

Thanks all!!

A lot of good info from you all and and I thank you all! I think I'm going to go with Tom Metzler's suggestion of cutting out the plugs and crimping the connections together since there is no longer a need for a replacement plug. I kind of like the crimp suggestion better because I think it's a simpler solution, doesn't create a need for me to figure out how to waterproof a terminal strip, and find a place to put it all. BTW, Christian, I read your rebuild on the cockpit gauges and what you said about the blower switch (formerly know as the oil light test switch :roll eyes: ) and the no real need to have a blower in a diesel boat. True, but I noticed that when I use mine on long hauls it helps to pull a lot of heat out of the engine compartment. I can feel it coming out of the port stern cowling while were underway. Not sure how much good that does but I guess less heat in the boat is better? Yes? I also do have a voltmeter on my boat which I believe the PO installed to replace the ammeter and I agree that it's a more useful gauge to have overall. The only other difference I have on my cockpit control is a key start rather then a button. I guess going either way isn't wrong. We did misplace the key one day and have to use a spare until we found the original. Having a button maybe leave the door open for someone to steal the boat but where they gonna hide it!! :0305_bigg

 

[Christian Williams]

Regarding almost everything, I have to remember where I live. There is probably often a 30-degree difference in our respective ambient temps. Here the cooling water is 68 or less. Not the same as rounding Thomas Point Light at noon in August.

My new temp gauge never gets above 160F, and neither did the old one.

 

[Tom Metzger]

A great disappointment

My new temp gauge never gets above 160F, and neither did the old one.

It must be a great disappointment to change out the gauges to get better numbers and find the new ones read the same.

 

[Emerald]

. Not the same as rounding Thomas Point Light at noon in August.

.

you mean skillfully drifting backwards "on purpose"?.......

 

[lnill]

Engine temp

Regarding almost everything, I have to remember where I live. There is probably often a 30-degree difference in our respective ambient temps. Here the cooling water is 68 or less. Not the same as rounding Thomas Point Light at noon in August.

My new temp gauge never gets above 160F, and neither did the old one.

I was told that 180 will get better combustion, less soot on the transom, and better power. I switched to a 180 thermostat last year (but I also had the injector pump rebuilt at the same time). At any rate I do see less soot and power is good.

As as for re-wire/gage replace I followed your links last year. I went with buss bars.