Engine Wiring Harness Question(Critical Upgrade)

[Mark Sutherland]

I'm having a mechanic replace my engine panel on my '86 next Monday.  I gave him all of this site's info and instructions pertaining to the engine wiring harness "Critical upgrade".  My question is, does ALL of the existing wiring between the engine and the panel necessarily need to be replaced or is it possible that 25 year old wiring could still be in satisfactory condition?  I told him to "use his judgement" as to whether to replace entire wire runs.  Would appreciate your input.  Thanks.

[Les Luzar]

Mike,
When I bought my new Instrument panel from Seaward Products I also purchased a brand new wiring harness (a little extended lenghth) because why not replace all of that 20+ year old wires. I would highly recommend the replacement with new wires. This makes the job easier and gives you the piece of mind that all of that wire is new and should be trouble free.  Also, as I recall, some of the old wire colors may be different so it is easier to install all new panels and wiring. Do it right the first time and you will be much happier going forward.

[Ron Hill]

Mark : To answer your question - it's not the wiring that's bad - its the connectors!! 
and in your case the elimination of the Ampmeter and the rerouting of the alternator output

Please read the upgrade. 

[Mark Sutherland]

I understand Ron. I will indeed have the mechanic replace all connectors and re-route the Ammeter connection.  I just want to know if you would have an issue using the existing(perhaps original) wire, or if you would spend the extra $300 or so to replace all of the wiring with new wires.  Thanks.

[Stu Jackson]

Mark, it really is your call.  As you know (from doing your homework - thanks, BTW! ) there are three parts to the upgrade: the ammeter, the trailer connections and the wiring.  Your question is the wiring itself.

On my 1986 boat, the PO did the first two, and it appears he left the original wiring.  Many folks have done that, because as Ron says, the danger is the connectors, and the improvement in charging is the ammeter removal/replacement.  My 1986 wires are working just fine.

This is a real-world example of "Your boat, your choice."  It'd be easy to say: "Change them," but I don't want to do that 'cuz it's YOUR money!

I think what you need to decide, more importantly than the wire replacement question, is how you want to connect them, as in Reply #32 in the Critical Upgrades (http://c34.org/bbs/index.php/topic,5078.msg44056.html#msg44056).  

[Added 12/5/2011] - Linked that one back to this topic.  Stu

If you keep the old wiring, I suggest you have them hard wire the ends, rather than using the Euro strips.  As I noted, I do have the Euro strips, but they were put in by PO.  In fact, I think my cockpit panel end was hard wired, no Euro strip there, only at the engine end.  If I was doing it myself, I'd hard wire it.  Hard wiring would make the decision to keep the old wiring much easier 'cuz you'd know you had good connections at each end.  Tinning the wires for the tiny Euro strip connections is time consuming, too.

[Ron Hill]

Mark : To change all of the wires or not??

I'll recommend that that decision is between you and your mechanic.   If the mechanic says that the wires are in good condition with no corrosion/breaks/cuts and you are satisfied, I'd go with what you've got.

When I wrote the article on installing a new engine, I recommended that people install the wiring harness upgrade by NOT using the euro strips and hard wiring the direct to the engine.  That harness with the plugs was installed for ease on the factory assembly line. 
I've removed my old engine and reinstalled it twice and as I said installed a new engine -- each of those times I disconnected and reconnected directly at the engine.  I NEVER touched those euro strips!!!
When I say "I" - I mean ME doing the work by myself!

Good Luck,  A few thoughts

[Stu Jackson]

Ron, if Mark is having a mechanic doing his wiring instead of an electrician, he's got a whole different problem. 

[2ndwish]

Mark- if you want to replace the wires seaward will sell you a harness pretinned and with eyelets crimped
For about 100$. It was actually easier than dealing with the euro terminals. We had ours made a couple of feet longer so that the panel can be serviced.sorry foi the iPhone typos but this is what we have been reduced to on the other side of town
T

[Ralph Masters]

If a mechanic is doing it you may as well stay with the plugs.   

Seriously, leave the wires in place, cut the wires one at a time, solder and shrink wrap them and move to the next wire, repeat on the other end.  Take the plugs up to the cockpit and see how far off the port side you can throw them.

Ralph

[Indian Falls]

Unless the wiring is too short to work with or has a lot of chafing and wear/tear on the insulation, I wouldn't waste the money changing them.  I removed my trailer plugs this spring. It took an hour to cut out the plug, strip the wire ends, and put in a 12 position Euro terminal strip that cost 4$.  It took a bit longer at the engine because of the awkward position I had to be in. 

I got em out there about 22 yards off the port side from my cockpit.

[Ron Hill]

What I've found on the right coast is that usually a good mechanic is also a more than fair electrician. 

All you have to do is look at the wiring ends + insulated jacket and determine if the wire needs to be replaced.  If the ends have cooroded wire and you have to cut more than 6 inches off to find shinny copper, I'd junk that wire for a new one.

Of course I'm a mechanic and a plumber, never professing to be an electrician. 

[Mark Sutherland]

Thanks for the advice everyone.  It was very helpful.  My mechanic hard wired everything.  He said the existing lower connecter "fell apart in his hand".   Thanks again. 

[Ralph Masters]

Mark,
Sounds like you made the right move.  Good luck and smoothe sailing.

Ralph