Burnt bulkhead connector, and some general wiring Q's.

[_Russ_]

OK, so I have some questions regarding a new wiring harness, and I though it best I start a new thread to keep it all in 1 place, rather than hijack others threads.

Here is the original thread I began when my Challenger's problems first occurred: Diagnosing a "miss" - fuel or electrical?. Engine dieing. Towed home. Starts a couple days later. Repeat. Multiple times over the past couple months. I thought it may have been the ignition, but also went through the fuel system. The "miss" was fixed by proper timing & advance adjustments, but it still cut out on me.

Matt is having a similar problem in his thread here.

After reading some thoughts in his posts, and other threads linked to regarding the Ammeter gauge and burnt bulkhead connectors, I started with my bulkhead connector and noticed part of it is burnt through. Can anyone recognise what that port/wire is used for?






An auto-electrician had previously told me I was getting a voltage drop from this area (but he didn't specify which wire), as well as this fusible link:




With the burnt bulkhead connector, and some old looking wiring, Ive decided to replace the engine wiring harness. Here are a few questions.


1) I'll be getting the M&H Harness from YearOne. I have electronic ignition, but will be switching to a complete aftermarket electronic ignition (ICE Ignition). The YearOne link mentions that "If using an aftermarket electronic ignition system, our manufacturer suggests that a reproduction harness for point ignition would be a better starting point." Is this correct?  Any thoughts on why that would be the case? (I'm not doubting it. Just curious).


2) Does anybody reproduce the 70 E-Body bulkhead fuse box? (The bit that's burnt in the above image). I don't believe this is included in the new harness, and I'll need to replace it.


3) Regarding the Ammeter bypass, I read on a Charger forum that Redline Gauge Works will actually convert your factory Ammeter gauge to a Voltmeter gauge. Has anybody had this done? Successfully? I'd much prefer that than aftermarket gauges.


I'll probably have a few more questions as I go. This should be enough to get me started.



I appreciate your time and any thoughts.

I've never been able to wrap my head around electrics. My aptitude for this sort of thing is best when I have someone experienced next to me and teaching me first hand on the job, as apposed to reading books and looking at diagrams that I can't make heads or tails of 

 

[don340-4]

  I think my M&H dash harness came with a new fuse box, my connectors looked like yours, I replaced the engine & light harness too, everything is good now. M&H is really good quality.

     

[anlauto]

Reaplace ALL harnesses with new M & H and be done with it.
It's a little expensive, but so is standing on the side of the road watching your car burn to the ground.... 

[don340-4]

     

[_Russ_]

Yeah that sounds like the sensible option. Unplugged everything at the bulkhead connector and found another burnt out port, which I believe is the troublesome Ammeter connection. Could be the very source of my problems.

New M&H Engine and Dash harnesses on the way.

[johannes]

Be aware of other connectors also !

I strongly recommend to run a wire in parallell with the AMP-meter....
Effectively running from alternator output, to battery +.

The movement of the AMP-meter needle will be reduced, but there WILL still be indication as to charging or draining the battery

[_Russ_]

That's actually what my auto-sparky did.

Fit the new ICE Ignition system, but run a wire from the ALT directly to the battery to take off some of the load. Car is now moving under its own power with excellent spark. Just need a dyno tune to get it tip-top.

[72ls5fla]

I just did the M&H main harness and engine harness on my car.
I had the same short situation and mine actually came close to catching fire.

The M&H harness is excellent reproduction.  No issues with connections/terminals missing etc..
I did have to reuse my fuse block section (not bulkhead) from my old harness so I could get my horn relay (correct 1970) to plug in.

The bulkhead (part screwed to the firewall) was the same -

You can use the new harness as shipped by using the horn relay they ship with the harness - there is a tab on the side that you will need to remove to make clearance to plug into the fuse block.
Be sure you put PLENTY of di-electric grease into the bulkhead (female connections).  This will keep moisture from getting in plus stop arching from dry loose terminals.

Just an FYI --   fit the new engine/lamp harness connectors to the bulkhead before you put the main harness in the car.  you may need to massage things a little to get them to clip down correctly..



FWIW --  I would do the forward lamp harness too ..    you will get a new fusable link wire section plus the plug for the bulkhead will be new and clean.
The harnesses are all discount allowable from YearOne.   I would wait for a 20% or 30% off web sale.  I saved enough on the main harness to basically get the engine harness and a good bit of the lamp harness for free...

Bill