Fusible Links Smoking

[SteveJ]

Does your meter autoscale? A reading of 1.84 ohms would translate into 7A of current. That won't blow a fusible link, but that's a strong drain. Did you make sure all of the switches were off? ( @Captain Obvious I beat you to the question. 😉 )

By outside front, I'm going to assume that is the black fusible link in the picture Capt posted. That has 3 connections at the alternator:

1. Condensor
2. Battery terminal
3. Sense terminal

Make sure all three are unplugged. It also runs to the ignition relay and fuse box. It feeds a bunch of circuits.

You can isolate the alternator from all of those circuits by unplugging connector C-9 and taking the resistance measurement again. C-9 is a 6 wire connector in the passenger footwell with the other engine harness to dash harness connectors. By the way, testing an internally regulated alternator that I have handy, I saw 2.2K ohm from the B to E terminals. 

[mayolives]

I have too many z cars so this 78 280 is an outside project and weather has prevented me from completing some suggestions of what I should test next.  However, I'll respond to a few comments listed in this thead.  My ohmmeter does autoscale.  I haven't found any other things like lights, etc that are truned on and causing a drain.  But I haven't hooked up my battery again since I smoked the fusible link.  The fusible link connection that I had the readings on (1.84 and 1.032) was the black one that is to the alternator.   

The photos below are of my alternator wiring, starter wiring at the starter, the other two connecters with green wiring in holders mounted on the side of the relay box, and another unrelated photo of a device mounted beside my new coil.  It's in the right top portion of the photo.  It's the small six sided plastic box with two wires.  What is it?  I can't locate it in my FSM.

My next steps for tests will be removing some fuses in the fuse block and unplugging connector C-9.  Thanks for all the advice thus far.  

[Zed Head]

44 minutes ago, mayolives said:

It's the small six sided plastic box with two wires

Those are the distributor "trigger" wires to the ignition module.  They only have voltage when the distributor is spinning.  Edit - actually those must be the wires up to the ignition module in the cabin.  So they're dead, no voltage.

Nothing obvious in your pictures.  "New coil" seems like a possible problem source.  I think that it's more than just a coil, it's an ignition system.  It has power and ground circuits, one of those misconnected could cause your issue.

Instead of going to the fuse box you might disconnect the things that have positive wires connected to them then see if your battery positive cable has a path to ground.  Leave the battery disconnected and you can't smoke any wires or fuses.

I think that FAST bought Crane's technology.  The FAST site is very poor, but Summit has old instructions.

https://static.summitracing.com/global/images/instructions/xr700 instructions.pdf

Edited November 5, 2021 by Zed Head

[SteveJ]

Here are some suggested steps. Some of these I have already provided.

1. Disconnect C-9 and check resistance on the alternator side of the black fusible link to ground. 
2. If the resistance went up, go to #5.
3. If you still have low resistance, disconnect all of the white/red (W/R) wires (including the one to the condensor). Measure resistance at the fusible link again.
4. If the resistance at the link went up, check resistance to ground at your alternator where all of the W/R wires were connected. Otherwise, you likely have a problem in your wiring harness.
5. With C-9 still unplugged, measure resistance from the (W/R) to ground. You can do that at the fuse box. Just select the right side of any of the fuses I circled.
6. If the fuses were in the fuse box with high resistance, remove the fuses and measure again.
7. If the resistance is still high, unplug the ignition relay and measure again.

Record your results, and also take photos.

As for the wiring at the coil, is that an I91, E92, or E93 coil? I recognize the red, yellow, black wire bundle as probably being from a Crane ignition system. It makes me wonder what distributor is in the car, since the Crane optical trigger was designed to replace the points, not a reluctor.

[mayolives]

21 hours ago, Zed Head said:

I think that FAST bought Crane's technology.  The FAST site is very poor, but Summit has old instructions.

Yes Fast is the "new" Crane and is now part of the Holley products line up.  Good wiring instructions were included with the ignition system.  This is the second Fast system that I installed on L6 engines.  The first one worked fine.  This one is the XR3000.  It has an ingition module that I mounted futher back on the inner fender, and the optically triggered parts that replaced the original pick up parts in my Hitachi distributor .  The installation was straight forward and I installed it according to the instructions.  I used thier I91 coil that a Fast tech person said I should use with this system.   

Edited November 6, 2021 by mayolives

[Zed Head]

20 minutes ago, mayolives said:

I installed it according to the instructions. 

It's new and you have a new problem.  FAST and Holley and Crane are all just brand names now, supported by big marketing.  Many of the names are actually part of the same big corporation.  The product manufacturing has all been outsourced to the least expensive contractor.

Won't hurt to disconnect it and be sure it's not the source.  Trust, but verify.

https://en.wikipedia.org/wiki/Holley_Performance_Products

Effective June 22, 2010, Holley emerged from bankruptcy protection.^[33]

In 2012, the private equity firm Monomoy Capital Partners acquired Holley Performance Products.^[34]

In 2013, Monomoy Capital Partners sold Holley to Lincolnshire Equity Fund IV, L.P.^[35]

In 2015, Holley acquired the MSD Group which includes MSD Performance, Mr. Gasket, Accel, Superchips, Edge, Racepak, Mallory, Hays, QuickTime, and Lakewood.^[36]

in 2018, Lincolnshire Equity IV, L.P. sold Holley to Sentinel Partners who merged the company with its Driven Performance Brands

[mayolives]

21 hours ago, SteveJ said:

As for the wiring at the coil, is that an I91, E92, or E93 coil? I recognize the red, yellow, black wire bundle as probably being from a Crane ignition system. It makes me wonder what distributor is in the car, since the Crane optical trigger was designed to replace the points, not a reluctor.

The coil is the I91 series.  The Fast tech person told me to use it.  The included instructions for my Hitachi distributor had step by step instructions for removing the original stator, reluctor and other internal parts befor installing the new Fast parts.  My distributor is a new (rebuilt) unit and it's part number was the correct one for this car.

Edited November 6, 2021 by mayolives

[Zed Head]

Here's the more relevant industry news for Crane.

https://www.cpgnation.com/wp-content/uploads/2015/12/FAST-Unveils-New-Ignition-Division.pdf

In 2001, FAST® was acquired by the COMP Performance Group™

https://www.aftermarketnews.com/edelbrock-owner-acquires-comp-performance-group/

Industrial Opportunity Partners (IOP), an operations-focused private equity firm based in Evanston, Illinois, and owner of Edelbrock LLC, has announced the acquisition of the COMP Performance Group.

[mayolives]

I'm always concerned when big companies take over the smaller ones.  But it's just what's going on out there these days.  We almost must live with it or do without!

[Zed Head]

My basic point is - your ignition system might be bad, or incorrectly wired, despite the fact that i's new and you followed instructions.  Disconnect, test, know.  Use the process of elimination.

[Zed Head]

On 10/9/2021 at 11:03 AM, mayolives said:

The major things i've done so far are installing new starter, alternator, distributor with fast xr3000 ignition module with distributor internals and matching Fast coil along with new plug wires, etc.

Upon attempting to start the engine for the first time the fusible links under the two white plastic covers on left side produced some smoke

Just a look back at the start of the problem.  All of the new electrical connections should be examined for correctness.  Any one of the three could be the source of the problem. 

But, if you take your first post literally, then the problem happened with the key at Start.  That narrows things down to the circuits involved in starting.   It might be though, that the smoking happened when you turned the key on.  Whatever it is though, the circuits initiated by the key seem to be involved.  Unless the smoking started as soon as you connected the battery terminals.

I'm just offering a different way to address the problem.  Your first post actually leaves a lot out that could be important.

If I had the problem I would disconnect the battery, and check the positive cable resistance to ground with the key in whatever spot it was in when the smoking started.  Remove loads until resistance rises to the appropriate level.  

[SteveJ]

46 minutes ago, Zed Head said:

My basic point is - your ignition system might be bad, or incorrectly wired, despite the fact that i's new and you followed instructions.  Disconnect, test, know.  Use the process of elimination.

For the Crane, red goes to coil positive and yellow goes to coil negative. The black/white wire that is hot when the key is in Start or On is on the coil positive. Why is the green wire on coil negative? It would either go to the distributor or to the TIU. Neither one is in service, so it could be pulled off the coil negative.

Has the TIU been disconnected? It doesn't work with your (@mayolives) setup anymore. 

Edited November 6, 2021 by SteveJ