Universal Wiring Harness Upgrade

[mainesail]

I know Ron and Stu have been harping on this for years but I still come across boats almost daily without these upgrades. Finally dug out some images from my library and put it into words & pics.. Hopefully this will make it more easily understandable...


http://www.pbase.com/mainecruising/universal_wiring_harness_upgrade

This one's easier to read:  http://forums.catalina.sailboatowners.com/showthread.php?t=135558

[Stu]

[David Urscheler]

Wow! Terrific post. This belongs in the Tech Wiki.

[Stu Jackson]

Maine Sail's great http://www.pbase.com/mainecruising/universal_wiring_harness_upgrade  has been added to the "Ammeters & Shunts 101" http://c34.org/bbs/index.php/topic,6032.0.html and placed in the tech wiki under Engine, as well as added a link in the Critical Upgrades, page 2 repeat discussion about the wiring harness.

I think we've got it covered.

Now, how many folks STILL haven't done it?

Please also note that Maine Sail recommends removing the alternator output from the 1-2-B switch C post and running it to the house bank, as he & I have have been suggesting for many years.

Read more in the "Electrical 101" topic in the "101 Topics" sticky.

[David Sanner]

Still haven't done it?

That would be me Stu, well kind of...

I've done the short-cut version which is not as good as a full
replacement but far better than not doing anything.

I've removed all the high amperage circuits which were
responsible for the overheating, melting and danger.

First and probably most important (and easiest) I rewired
the output from my alternator removing the long and dangerous
run up and back to the ammeter on the engine panel. I
then replaced that with a volt meter.   It's easy so if you
still have the original ammeter at least do this part.
... actually follow Stu's full recommendation, I'm not an
 example that should be followed  ;)  but it is far better
than not doing anything.

Second I did the glow-plug/solenoid improvement which avoids
the second long/hi-amperage run that goes through the
wiring harness and suspect plug.  It also shortened the
time I have to hold the glow plug button quite a bit.

I have since cleaned and inspected the suspect plug and
one of these days I'm going to do the last step and cut
it out and replace it with a terminal strip... the one that has
been sitting in my chart table for the last few years.

Higher on my to-do list is replacing my Tach/Hourmeter.
Just need to find one that matches the alternator for a
reasonable price... anyone have a good/bargain source?

[Ron Hill]

David : Whether you know it or not you are "playing with fire" and :
You definitely have NOT read my write up in the Mainsheet tech notes from about 1997?.

So, Let me give you a synopsis as it's definitely worth repeating :

I first heard about the wiring harness upgrade from Gerry Douglas at Sail Expo in Alantic City in 1992?  I had had some problems with my Auto Mac alternator (OEM) controller in 1990 and couldn't figure out why.  So I junked the Auto Mac (it was actually seeing alternator voltage instead of battery voltage at the key switch - the screwy + wiring being the cause) so I installed a Balmar duel output alternator in about 1992.
 
Thought I'd solved the problem (just like you) by eliminating that amperage circuit back to the key switch and  back to the Perko switch and then finally to the batteries .  I had a Voltmeter in my engine instrument panel so with the routing of the alternator output DIRECT to the batteries, all should be OK - I thought.  (funny that NOW, direct to the battery is the way to go!)

Previously, as a "Curious George" I had found, opened and examined the 8 pin trailer connector at the engine and put it all back together again.  All was OK
Based on what I had heard from Gerry Douglas, I immediately had purchased a wiring harness upgrade kit from Seaward, but with the new Balmar wiring thought I really had spent some unnecessary money - and put it in with my spare parts on the boat.

About a year later I thought that maybe I should connect the wires to that Euro Block that I had purchase.  
So one day I decided to take that 8 pin trailer apart and finally install the "upgrade" .

TO MY SURPRISE, WHEN I TOOK THE TAPE OFF THE 8 PIN TRAILER CONNECTOR at the engine  - THE CONNECTOR FELL APART/DISNITERATED IN MY HAND !!

I didn't have a short circuit between wires! All I can guess is that between the engine heat and the old amperage heat BOTH helped disintergrated the plastic connector?!?

I can say is that ALL of the Wiring Harness Upgrade need to be install -- or you can still run into problems !!


Guys : Enough said.   The old Mainsheet tech note are available to all of you.  They contain solutions to 99.99% of all problems that previous owners have already encountered and SOLVED!!!!!

[Stu Jackson]

Higher on my to-do list is replacing my Tach/Hourmeter.
Just need to find one that matches the alternator for a
reasonable price... anyone have a good/bargain source?

Dave, it sure sounds like you have reasonably addressed the "issues" related to the potential melting of those connectors by doing what you've done so far.

As far as the combined tach/hour meter, I'd try Seaward.  I've looked at the Teleflex models in the WM catalog and couldn't find one with both.  Your choice is to find a combined meter, or just buy a less expensive tach and install a separate hour meter (which doesn't have to be in the cockpit panel).

[Stu Jackson]

Here's another update to the Critical Upgrades topic on this subject:  http://c34.org/bbs/index.php/topic,5078.msg44056.html#msg44056