If you try and "crush" the rivnut to get it tighter, it will loosen back up. Crimp it down tight and call it good.
96 GMC K2500 Suburban Restoration (with a couple of mods)
- Thread starter South VA
- Start date
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
Good to know - thanks!
The rivnut kit showed up, and I installed a ¼-20 in the existing hole, after drilling the hole out a bit.
I tested the ground with the multimeter to verify continuity, and measured zero resistance between it and the alternator housing, and between it and the battery negative terminal (battery is out of the vehicle at the moment).
Of course I don't have a proper bolt to fit the rivnut, so I'll have to pick one up this morning.
However, in the process of getting the air cleaner housing out of the way to make room for the rivnut tool to work, I discovered that the packrat had chewed a substantial portion of the sheath on the battery ground cable to the starter and alternator.
For some reason, the positive cable wasn't affected.
The negative cable looks largely intact. I thought about wrapping it with tape and calling it good, but decided that I'll replace it with new cable.
For now I'll wrap it in electrical tape and run it as-is. I'm anxious to see if this thing will start and run once I get all the connections made.
You must be registered for see images attach
I tested the ground with the multimeter to verify continuity, and measured zero resistance between it and the alternator housing, and between it and the battery negative terminal (battery is out of the vehicle at the moment).
Of course I don't have a proper bolt to fit the rivnut, so I'll have to pick one up this morning.
However, in the process of getting the air cleaner housing out of the way to make room for the rivnut tool to work, I discovered that the packrat had chewed a substantial portion of the sheath on the battery ground cable to the starter and alternator.
You must be registered for see images attach
For some reason, the positive cable wasn't affected.
The negative cable looks largely intact. I thought about wrapping it with tape and calling it good, but decided that I'll replace it with new cable.
For now I'll wrap it in electrical tape and run it as-is. I'm anxious to see if this thing will start and run once I get all the connections made.
Found a bolt for the rivnut, added a couple of washers, and tightened it up snug. I had not been able to apply that much torque to the original bolt through the body; a huge improvement.
The only concern I have is that the surface area of the ground has been reduced to the area of the rivnut rim plus the amount of the bolt thread in contact with the rivnut. Not sure if it will be enough. We'll see.
With the new battery connected, it started right up. The new ignition switch appears to be working.
I checked voltages at the battery terminals, and then between the positive battery terminal and the chassis by the radiator cap. There's a .1 - .2 volt difference between the two locations. Not sure why, and don't know if it's a problem or not. Wish I knew more about this stuff.
I also sprayed some more foaming cleaner onto the evaporator, and put the blower back in to test the AC.
Air from the vents is blowing more forcefully - not like new, but noticeably better - and it doesn't stink any more! I'll know for sure once the cleaning foam has all drained out. At first it was draining onto the passenger floormat, but then started coming out from underneath the passenger side. I'm wondering if I could run some sort of a flexible rod up into the drain opening to unplug it. It appears that the cleaning foam has dissolved at least some of whatever is in there.
Anyway, I let it idle for about 20 minutes with the AC on, to complete the cleaning process per the foam manufacturer's directions. I'll probably spray the rest of the can in there before final assembly.
I also managed to get the new antenna cable installed. The job looked worse than it turned out to be.
Fortunately I had a 7/32 socket on hand!
It's a mess, but it starts and runs.
I debated whether to go ahead and put the dash panels back in now and drive it for a week or two, to make sure the charging and shifting issues are resolved, or to wait for the new soldering gun and shrink tube assortment to arrive tomorrow so I that can finish installing the sound system and backup camera. After today I won't be able to work on it until next week, as I have some other commitments, but I'm leaning towards finishing everything up next week.
Feels like progress!
The only concern I have is that the surface area of the ground has been reduced to the area of the rivnut rim plus the amount of the bolt thread in contact with the rivnut. Not sure if it will be enough. We'll see.
You must be registered for see images attach
With the new battery connected, it started right up. The new ignition switch appears to be working.
I checked voltages at the battery terminals, and then between the positive battery terminal and the chassis by the radiator cap. There's a .1 - .2 volt difference between the two locations. Not sure why, and don't know if it's a problem or not. Wish I knew more about this stuff.
I also sprayed some more foaming cleaner onto the evaporator, and put the blower back in to test the AC.
Air from the vents is blowing more forcefully - not like new, but noticeably better - and it doesn't stink any more! I'll know for sure once the cleaning foam has all drained out. At first it was draining onto the passenger floormat, but then started coming out from underneath the passenger side. I'm wondering if I could run some sort of a flexible rod up into the drain opening to unplug it. It appears that the cleaning foam has dissolved at least some of whatever is in there.
Anyway, I let it idle for about 20 minutes with the AC on, to complete the cleaning process per the foam manufacturer's directions. I'll probably spray the rest of the can in there before final assembly.
I also managed to get the new antenna cable installed. The job looked worse than it turned out to be.
You must be registered for see images attach
Fortunately I had a 7/32 socket on hand!
You must be registered for see images attach
It's a mess, but it starts and runs.
You must be registered for see images attach
I debated whether to go ahead and put the dash panels back in now and drive it for a week or two, to make sure the charging and shifting issues are resolved, or to wait for the new soldering gun and shrink tube assortment to arrive tomorrow so I that can finish installing the sound system and backup camera. After today I won't be able to work on it until next week, as I have some other commitments, but I'm leaning towards finishing everything up next week.
Feels like progress!
Hey South VA,
I just read through your entire string. Great photos & documentation
of all the trials & tribulations that come with bringing an older
vehicle not up to just a pretty trailer queen performance level
(ie: just good enuf to get on & off the trailer) ...but instead be
pretty AND make it deliver on what the original designers promised. (!)
As for the color, if I were to be graced with a winning lottery ticket &
go all Jay Leno on the GMT400 product line, that Emerald Green Metallic
would be at the top of my wish list. Love that color, it's right up
there with what the used car mfg plant gave me. :0)
Let's see, what else. Oh yeah, on top of everything else, today
the word NEW is sometimes also an acronym for Never, Ever, Worked.
Trust, but Verify is the only way.
****
While reading your tale of wiring harness woe, it reminded me of a
old 4-eye Mustang Convertible with a highly desirable (to me)
5.0/5-speed drivetrain. Easy on the eyes, but after several attempts
to correct the battery going flat every couple of daze, I was seeing
red. Whenever I looked at the car, it's all I could think about. Looks
Good, Runs Bad -- I much prefer the opposite! :0)
Taming the underdash Wiring Harness from hell -- exorcising the PO's aftermarket anti-theft system & restoring good order
You must be registered for see images attach
Sometimes a picture really is worth a 1000 words. Finally I stopped trying to fix this while standing on my head, pulled the dash,
and danced this mess around until it was conquered. (This photo brings back some strong memories. :0)
Anyway, I came this close to giving up on the car & just selling it,
but I knew that if I could just get the harness back to the same
condition as it was when it popped off the assembly line it would
be OK. And it was. (NOTE: Every single hack spot in the harness
was repaired using the Western Union splice, then soldered, followed
by good quality heat shrink. After paying my mortgage chasing
other people's intermittents, I can't stand them in my own pleasure
vehicle(s) -- I'm trying to escape work, not relive it! :0)
****
To summarize, from here in upstate NY it looks like you are doing
great work. There is definitely something to the 'Built, Not Bought'
approach to the hobby. And I hope that you don't give up on your
'burb & get a fresh set of issues to work through on the replacement
vehicle.
Safe Travels --
Last edited:
Thank you for your kind words and encouragement. It helps - a lot.
As for the color, I too love it; hands-down my favorite of all the colors available for the GMT400s. Oddly enough, color was not one of my main criteria when I was looking for a Suburban, so I feel pretty fortunate to have found this one.
Yes, there was a brief period when I thought that I’d made a terrible mistake in buying this vehicle, and was wondering the best way to get rid of it, but after further thought I realized that any vehicle of that vintage would have issues, so I recommitted to seeing it through.
True, this particular Suburban maybe may have a few more issues than one would normally expect due to the packrat’s having taken up residence in the engine compartment while it was parked for awhile. I continue to find previously unnoticed places that have been gnawed by its nasty little teeth.
Looking at my last post 10 days ago I thought I’d be further along by now; but the heat has been a bit much for me to work on it, as it’s not in a garage or even under a decent shade tree. I don’t do heat very well.
In the meantime I’ve been further educating myself, mainly on youtube and other forums and 12v-oriented websites, on electrical issues and stereo installation. As a result I’ve learned some good stuff and ordered more parts and tools. Yippee!
Funny you should mention the Western Union splice, as I just read a reference to that yesterday. I was going to look it up, but you thoughtfully provided a link. I will definitely use that method from here on out. Thanks!
I have also been reading up on the use of ferrules with cable in set screw terminals. And, of course, I had to order some ferrules and a crimper. Using them on stranded copper cables makes a lot of sense. Worth a try, anyway.
Once the main battery ground cable is replaced (the new cable finally arrives tomorrow), I’m also going to enlarge the battery to body ground I mentioned earlier in the thread. I’ll drill out the ¼ - 20 rivnut and install a larger one, along with some thicker ground wire. I’ll also check the main positive battery cable in case I missed something earlier. Getting to the cables will involve pulling the battery and air intake assembly, and probably more, but that’s fine. More room is better. Besides, I have to route the amp and subwoofer power wires through the firewall while I’m at it.
Speaking of the air intake, when I happened to look inside the air filter housing, I discovered that Mr. or Ms. Packrat had gotten inside of it and remodeled the
The new sound system is testing my installation skills, which is part of the reason I’ve been avoiding doing it. I’ve installed several systems in the past, but they were years apart and it seems that I have to relearn each time. This one ought to be fairly simple, with an amp that attaches to the rear of the shallow head unit (Alpine), a powered sub, and new door speakers, with component speakers in the front doors including tweeters. Routing the video wire for the backup camera has taken some head scratching and asking for advice in another thread, but I think I’ve sorted it out.
For awhile (also in another thread) I thought about removing the alarm system, as it would sometimes go off without apparent reason. I’ve since learned that it happens when there’s been an interruption to the battery connection, like when the alternator was replaced. Now that I know about the button on the underside of the dash that has to be pushed when starting (temporarily disabling the system) after the battery was disconnected, I’ve decided to leave the alarm installed. After repairing some chewed wires, that is.
A more recent issue is that the rear AC blower now only runs on High, and won’t shut off. I’m going to try replacing the blower motor resistor, assuming I can find one. If not, I’ll pull the fuse and run it without rear AC for now. In the scheme of things, I’m not worried about it.
Just to move things along a bit, I scheduled another camping trip for August 7. Call me crazy, but I need a deadline to work towards. So I figure that will give me enough time to finish everything up (working in the early mornings before it gets hot) and have a few days to test drive it before departure. At least that’s the plan.
More updates to follow.
Last edited:
As part of the USAF Avionics tech school back in the '70s, we
to attend a 3-day version of NASA's High Reliability Soldering Techniques
course. The instructors inspected your work mercilessly, and I certainly got my
money's worth, for I think I had to redo/retry every single thing I soldered
at least 3-5 times each. I had soldered in High School Electronics class, but
I was the king of cold solder joints...so I wanted to know what the secret
was. I enjoyed every second of this 3-day full-contact soldering training.
This training has served me well over the past 40+ years -- and if you are reading
this as a US taxpayer, that young airman wishes to *thank you* for
the opportunity that the military provided me. :0)
Guess where I learned about the Western Union splice? Yup, that NASA
soldering class. Check this out: (link)
Heck, I'll do you one better. Since you paid for this as a Taxpayer, and
by sharing this link I am not divulging the Capability of anything, do
yourself a favor and download a .pdf copy of the official NASA Technical Standard
titled "Workmanship Standard for Crimping, Interconnecting Cables, Harnesses,
& Wiring.
Follow this document, and your wiring will reliably outlast the rest
of the vehicle. Commit it to memory (like some of the Avionics elders
had managed to do) ...and you will become a true Subject Matter Expert
on all this stuff. (Note: Western Union Splices are covered, starting on pg. 82 of 113.)
Speaking of which, part of the reason why the Western Union splice is so
reliable and high performing, is because it forces you to make a tight physical connection
before you apply the solder. So many people think that the solder is the
conductor between 2 wires that may or may not be in direct contact. Wrong.
Keep in mind while referencing this manual that a tight physical interconnection between
2 wires is where the reliable conductance comes from -- the solder is only there to
A) keep the connection airtight & B) help ensure that the connection doesn't loosen
under stress/vibration. (ie: solder is nothing more than liquid > solid safety wire
for electrical connections. :0)
****
Q: How do I know that properly installed Western Union splices will
last a long time?
A: I'm a half-owner of a Factory Five Cobra replica. My good buddy
Paul & I built it around the turn of the century. He was the fabrication
master, and my end of the bargain was the drivetrain, suspension,
wiring, brakes, and misc. fiddly stuff. Here's a photo of me after a full day of
(WTF) wiring from scratch:
"May I be excused? My brain is full." -- (G. Larson)
You must be registered for see images attach
Ghz/Mhz RF is hard like calculus. 120/240V 60Hz AC can deliver a jolt if unwary. 12V DC is easy like addition. WTF? (Why The Face? :0)
(Time passes...)
Yours truly on I-495 last summer in same car, w/trademark SEG! Knock on wood -- Never once in the past 22 years have we experienced a wiring harness failure/gremlin.
Of course the wiring harness complexity is probably 1/20th that of the modern 'burban. But what little is there has remained Code 1 for the past couple of decades of go-karting.
You must be registered for see images attach
(Hopefully the fact that this car is painted Corvette Millennium Yellow will keep my driving this car from getting me kicked off the GMT400 forum.
Please be assured that my big block '99 C2500 entertains me just as much as this does...just in a different way.
****
I enjoyed your post, and consider myself fully briefed & up to speed on your project.
If knowing that there are several of us watching over your shoulder gives you that
wee bit of extra juice to divide & conquer the problems on your project, PERFECT.
Speaking for myself, if I have an idea & never say it in public, there's a good chance it won't happen.
On the other hand, IF I say something in public and others hear it, then I have no choice but to make it so.
Anyway, be sure to download that NASA .pdf file, and treat that Suburban like it's a
college-level hands-on course on real-world High Reliability wiring harness fabrication.
(Man, think what the tuition would be for that? The mind boggles... :0)
I'm going to join the folks already following your project & will be patiently waiting for updates.
But no pressure. No rushing.
Remember, "Quality is the Constant, and Time is the Variable."
Good Luck --
Last edited:
HotWheelsBurban
Gotta have 4 doors..... Rawhide, TOTY 2023!
The "magic button" is good to have, my CCLB has one on its aftermarket alarm (that may have been dealer installed or done at a shop shortly after the original owner bought it. It could function as a kill switch if you had the battery disconnected, since that's effectively what it does.
Finally pulled the main battery ground cable, which was shown in post # 63.
Here's the closeup:
There's some green oxidation on the strands. I'm replacing it with 2 AWG OFC. Now I just have to get the correct connector; I went to NAPA before the cable arrived and mistakenly got some 2/0 connectors, which of course are way too large.
I'm not sure how much of a role this chewed and oxidized cable played in my electrical woes, but I have to believe it's a factor.
One more variable eliminated.
You must be registered for see images attach
Here's the closeup:
You must be registered for see images attach
There's some green oxidation on the strands. I'm replacing it with 2 AWG OFC. Now I just have to get the correct connector; I went to NAPA before the cable arrived and mistakenly got some 2/0 connectors, which of course are way too large.
I'm not sure how much of a role this chewed and oxidized cable played in my electrical woes, but I have to believe it's a factor.
One more variable eliminated.
Got the correct size (2 AWG) ring terminal from NAPA (dang those things are expensive!) and made up the ground cable, with a ferrule at the battery end to go into the set screw battery terminal.
I'll be interested to see how well these terminals work. If they don't, at least they'll be easy enough to change out.
Now to upgrade the ground on the inner fender with an 8 gauge wire. I was considering drilling out the ¼ - 20 rivnut and putting in an M8, but decided to see how the resistance measures once the 8 gauge is installed before further modifications.
The bolt where the main ground cable attaches on the front of the engine is a pita to reach. Trying from above, which is a long reach, I probably got it tight enough, but I woke up thinking about it this morning and how it might come loose. So I crawled underneath to get better access, and now it is gutentight.
While I was at it I checked the engine to frame ground strap, and it appears to be intact. It wouldn't surprise me if it's been replaced at some point during the past 27 years.
I also verified that the positive lead to the starter has not been chewed, or at least has been replaced. Once I get this thing a bit higher off the ground, preferably on some ramps and on the lawn instead of on the gravel parking area, I may consider replacing it with 2 gauge wire. For now, it's going to stay as-is.
I really, really want a garage!!
You must be registered for see images attach
I'll be interested to see how well these terminals work. If they don't, at least they'll be easy enough to change out.
You must be registered for see images attach
Now to upgrade the ground on the inner fender with an 8 gauge wire. I was considering drilling out the ¼ - 20 rivnut and putting in an M8, but decided to see how the resistance measures once the 8 gauge is installed before further modifications.
The bolt where the main ground cable attaches on the front of the engine is a pita to reach. Trying from above, which is a long reach, I probably got it tight enough, but I woke up thinking about it this morning and how it might come loose. So I crawled underneath to get better access, and now it is gutentight.
While I was at it I checked the engine to frame ground strap, and it appears to be intact. It wouldn't surprise me if it's been replaced at some point during the past 27 years.
You must be registered for see images attach
I also verified that the positive lead to the starter has not been chewed, or at least has been replaced. Once I get this thing a bit higher off the ground, preferably on some ramps and on the lawn instead of on the gravel parking area, I may consider replacing it with 2 gauge wire. For now, it's going to stay as-is.
I really, really want a garage!!
