Cap & Rotor

[name]

Here are some pictures of the plugs :

 

[name]

Here are some pictures of the wires :

 

[name]

Seeing how we are on the subject of longevity, How long can you expect a Coil and ICM to last on a '94 5.7 ? My unit has 165K and the ICM appears to be original GM unit.

 

[Schurkey]

Near forever, IF the coil doesn't get overloaded/excessive secondary voltage due to failures of the plug wires or some copulating anthropoid deciding that the spark plugs need a gap big enough to push a kitten through.

Oh, sure...it's going to fail someday. But there's no expected service life that I'm aware of. They either fail right away from manufacturing defects (Infant Mortality) or they last indefinitely, often murdered by a failure "downstream".

If you're concerned, you could buy a respected-brand-name replacement module and coil, or you could do what I do. I grab OEM modules, coils, entire distributors, etc. out of the Treasure Yard, for pennies on the dollar compared to "new" cost. Test-run the parts BEFORE the original stuff fails, then keep 'em in reserve--in a plastic bag in the glove box, or wherever it's convenient. When (if) you have a failure on the road...you've got a proven-good replacement handy. Of course, the tools you need to change 'em will be at home, so you'll still be screwed.

 

[Scooterwrench]

I've been pleased with the United Motor Products blue vented distributor cap and rotor set with brass contacts, on both my 5.7 Vortecs. I live in Houston, Texas and humidity is something we suffer with here! So on a distributor like the Vortecs have, that is prone to gathering moisture, to have a way to prevent that is great. The trucks both ran better once those were installed too.

Those worked good for marine use also. Anything that can withstand salt water can withstand salted roads.

 

[Scooterwrench]

Near forever, IF the coil doesn't get overloaded/excessive secondary voltage due to failures of the plug wires or some copulating anthropoid deciding that the spark plugs need a gap big enough to push a kitten through.

Oh, sure...it's going to fail someday. But there's no expected service life that I'm aware of. They either fail right away from manufacturing defects (Infant Mortality) or they last indefinitely, often murdered by a failure "downstream".

If you're concerned, you could buy a respected-brand-name replacement module and coil, or you could do what I do. I grab OEM modules, coils, entire distributors, etc. out of the Treasure Yard, for pennies on the dollar compared to "new" cost. Test-run the parts BEFORE the original stuff fails, then keep 'em in reserve--in a plastic bag in the glove box, or wherever it's convenient. When (if) you have a failure on the road...you've got a proven-good replacement handy. Of course, the tools you need to change 'em will be at home, so you'll still be screwed.

As Shurkey said coils never die on their own. I've kept a GM ICM in my glovebox in every vehicle I've owned and never used it.

 

[name]

Is it safe to say that the pickup coil has the same " near forever " life span as the coil and ICM ? When I cleaned up the mess in the distributor left by the degrading cap and rotor I hosed it down with WD-40 and blew it out with compressed air, Then I removed the ICM and cleaned up the mounting area / base plate with carb and choke cleaner and a rag to remove the old thermal past and crusty debris , and then re-mounted the ICM with Artic Silver.

Is this the right procedure to address the mess I had in the above pictures ? ( mostly concerned with using the compressed air in the star wheel / pickup coil area after reading about some Magnets in the distributor , that I can not see ) This suburban is primarily used on road trips, so if it takes a ****, I am nowhere close to home.

 

[Schurkey]

Is it safe to say that the pickup coil has the same " near forever " life span as the coil and ICM ?

No.

The pickup coil wire insulation fails over time, the conductors within the insulation can break. The magnet near the pickup coil tends to crack by the rivets holding the parts together.

On earlier designs of the pickup coil, the magnet was part of the pickup coil rather than part of the mainshaft; and the pickup coil often moved on the shaft due to the action of the vacuum advance--so the older pickup coils had more problems than the TBI pickup coils aside from the magnet problem.

Then I removed the ICM and cleaned up the mounting area / base plate with carb and choke cleaner and a rag to remove the old thermal past and crusty debris , and then re-mounted the ICM with Artic Silver.

Did you assure that the screen vents are clear of debris? Aside from that, sounds good.

reading about some Magnets in the distributor , that I can not see )

Magnet cracked through the rivet, near the Copyright symbol.

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[name]

Looking at your first picture in post #28, and looking at my first picture in post #27 I would say that my magnet is cracked by one of the rivits also, hell I would go as far to say that your distributor looks better than mine.

Would these cracks cause a misfire or low idle ? I ask because I had time to take it out on a ride today and it seems like it has a misfire at idle, ( But it did appear to have better acceleration ) can these parts in the distributor be rebuilt ? I have a new ( made in china ) distributor that has been sitting in a closet that I have never used because I read a post a few years back about how they were junk, something about the bearings not getting any oil / ICM not worth a crap. Would I be better leaving the one I got in there and looking for a misfire somewhere else, of stuffing the $ 50. china unit in there ?

I did check the screens and they were clear.

 

[L31MaxExpress]

As Shurkey said coils never die on their own. I've kept a GM ICM in my glovebox in every vehicle I've owned and never used it.

I disagree, I have seen the insulation material crack and split and then they arc out internally.