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Ground fault after intake refresh

Old 08-09-2013, 02:54 PM
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While we're on the subject of re-building harnesses, does anyone have a trick for easily replacing the hardened, cracked and otherwise "jest fallin' apart" rubber insulating sheaths on the hundreds of spade connectors peppered throughout this engine? I hate to pull the entire harness just to re-insulated these terminations.

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Old 08-09-2013, 03:14 PM
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MainePorsche
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When I re-insulated mine, I had taken the whole harness out. I had cut new cable to length for the big power lines. This, on retrospect, will make it easier to re-insulate the bundles. What I used for insulation was fiberglass about 2 " wide in a 100' roll from an aircraft supply house. Rated for high thermal protection and mechanical protection. Over this I place a thick silicon tape. Again, a 100' foot roll from the same people. Meticulously, tightly and spirally wound each layer around my newly serviced and fabricated lines. Has been there for three years without a nick. Will be more difficult to tightly wind on if lines are in the car, but should be possible though. I am sorry I didn't keep the name/link to this supplier, but a search will find the material.
Old 08-09-2013, 04:10 PM
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Originally Posted by MainePorsche
What I used for insulation was fiberglass about 2 " wide in a 100' roll from an aircraft supply house. Rated for high thermal protection and mechanical protection. Over this I place a thick silicon tape
Sound much better than the factory harness sheath. What I was asking about though were just the rubber covers on the spade terminators themselves. I've thought about clipping off the lugs/spades and installing new ones with new insulating covers and stress relief but it would be tedious doing it in place unless there was a better way (I was thinking something like a slip on replacement). I wonder if heat shrink tube would work?

I'll probably just pull out the harnesses and re-build them as you did. Doing the injector harnesses might be tricky since I don't know where they go after leaving the engine compartment yet.

Thanks for the tip on the fiberglass wrap,
Old 08-09-2013, 04:23 PM
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MainePorsche
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Originally Posted by Pfc. Parts
Sound much better than the factory harness sheath. What I was asking about though were just the rubber covers on the spade terminators themselves. I've thought about clipping off the lugs/spades and installing new ones with new insulating covers and stress relief but it would be tedious doing it in place unless there was a better way (I was thinking something like a slip on replacement). I wonder if heat shrink tube would work?

I'll probably just pull out the harnesses and re-build them as you did. Doing the injector harnesses might be tricky since I don't know where they go after leaving the engine compartment yet.

Thanks for the tip on the fiberglass wrap,
You can heat wrap for whatever size you need. For me that was layer 1 of 3.
Old 08-09-2013, 07:19 PM
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Originally Posted by neilh
If your 14 pin looks like this, get ready to rebuild it!
Here's mine. I think I lose the contest for who has the worst looking connector.
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Old 08-09-2013, 07:24 PM
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Actually, not that bad.
That 4.0 mm to the starter is definitely in need of help.
Old 08-09-2013, 07:37 PM
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Originally Posted by MainePorsche
Actually, not that bad.
That 4.0 mm to the starter is definitely in need of help.
No kidding. That looks dangerous.
Old 08-09-2013, 07:43 PM
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Originally Posted by MainePorsche
When I re-insulated mine, I had taken the whole harness out. I had cut new cable to length for the big power lines. This, on retrospect, will make it easier to re-insulate the bundles. What I used for insulation was fiberglass about 2 " wide in a 100' roll from an aircraft supply house. Rated for high thermal protection and mechanical protection. Over this I place a thick silicon tape. Again, a 100' foot roll from the same people. Meticulously, tightly and spirally wound each layer around my newly serviced and fabricated lines. Has been there for three years without a nick. Will be more difficult to tightly wind on if lines are in the car, but should be possible though. I am sorry I didn't keep the name/link to this supplier, but a search will find the material.
That's cool right there, I need to follow that method. Can't ever seem to find the right insulation, need to go Aero...
Old 08-09-2013, 07:45 PM
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Originally Posted by MainePorsche
Actually, not that bad.
That 4.0 mm to the starter is definitely in need of help.
That's the one that got baked during the "great alternator fiasco" of 1987. It worries me...
Old 08-09-2013, 07:56 PM
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Originally Posted by Bill Ball
No kidding. That looks dangerous.
Hey Bill -

I noticed you're in NorCal, I'm planning to be at the Laguna Seca meet in November, I just re-joined last week in anticipation of getting my car back on the road after 15 years in storage.

If I can get it running again I'll be there, If anyone else is planing on it maybe you can give me some advice on what to do with "Dogbert"? I want to put the car on the track someday but I'll be running stock with the street car while I figure the lay of the landscape. Currently I'm thinking I'll be buying a couple of 16 valve heads...

Regards,
Old 08-09-2013, 08:00 PM
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Originally Posted by Pfc. Parts
That's the one that got baked during the "great alternator fiasco" of 1987. It worries me...
That is a very 'healthy' sized wire. If that got 'baked' within the harness insulation a fair amount of heat would be generated, probably melting some of the insulation on the smaller wires within the spaghetti bundle.

You may want to roll your sleeves up on this one and preventatively and/or reparatively address this.
Old 08-09-2013, 08:17 PM
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Originally Posted by MainePorsche
That is a very 'healthy' sized wire. If that got 'baked' within the harness insulation a fair amount of heat would be generated, probably melting some of the insulation on the smaller wires within the spaghetti bundle.

You may want to roll your sleeves up on this one and preventatively and/or reparatively address this.
Pardon me, I used too much artistic license.

It did get baked, to the point it had to be replaced. What I did was thread new primary wire (from the local auto parts store) through the harness and re-terminate it. That specific wire didn't get baked, it was the wire that got replaced, but it was the only wire I replaced. Since then it's shown those stress cracks you see, I don't think it was the best wire to use.

I agree. It's time (probably past time) to roll up my sleeves and re-build the entire harness.
Old 08-09-2013, 08:34 PM
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Originally Posted by Alan
Could be your battery is totally shot also.
And we have a winner!

As you guessed, the battery is totally shot. I had this idea it might be OK for awhile if the ground strap was disconnected. It probably would have been had it not been 15 years old and the subject of so many re-charges I can't even count them.

$275 for a new battery, the joy of finding the problem? Priceless.

I may be overly optimistic. I won't get the new battery until tomorrow.
Old 08-09-2013, 08:55 PM
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You don't need a $275 battery!
I got a Bosch at Pep Boys for less than $90
Old 08-09-2013, 09:10 PM
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Originally Posted by outbackgeorgia
You don't need a $275 battery!
I got a Bosch at Pep Boys for less than $90
Yeah, but did you get it 4 days before the Pebble Beach Concourse starts?

I made a strategically bad move on this one and I'm now paying for it. Honestly, I was so focused on getting the hard parts of an intake refresh finished in time I didn't even think about that d@amned battery!

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