Fuse box corrosion

Moderators: Sluggo, Amskeptic

Post Reply
User avatar
satchmo
Old School!
Location: Crosby, MN
Status: Offline

Fuse box corrosion

Post by satchmo » Sun Jan 06, 2013 11:26 am

The bus is having lots of electrical weirdness, so I decided to a little investigation into the rats nest of wires under the dash. I knew there had been an electrical fire there at one time, because I found tons of residue from the fire extinguisher that was used to put it out when I took the upper dash off to refresh the wiper motor, and I had seen some burnt paint and melted wire casing.

But the corrosion I found in the fuse box was a little surprising:

Image

The parking lights up front haven't been working, the brake lights are iffy, the left side high beam doesn't activate, and the turn signals are schizo. Now I know why. Several wires have melted casing in places, but no metal/wire is exposed.

I can label and remove every wire, clean up the fuse box, and refit, but what do I use to clean the connectors? An emery board is too big to get in and file the inside of the connector, and I can't imagine trying to sandpaper out each one. Would battery terminal cleaner work? What is causing this corrosion?

Suggestions welcome. Also, maybe someone could submit a photo of how these wires were originally bundled so it doesn't look like spaghetti under there when I am done.

Tim
78 Westy 59,000 miles
By three methods we may learn wisdom:
First, by reflection, which is noblest;
second, by immitation, which is easiest;
and third, by experience, which is bitterest. -Confucius

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Fuse box corrosion

Post by Amskeptic » Sun Jan 06, 2013 11:54 am

satchmo wrote:residue from the fire extinguisher
corrosion was a little surprising:

Also, maybe someone could submit a photo of how these wires were originally bundled so it doesn't look like spaghetti under there when I am done.
That corrosion looks a lot like fire extinguisher salts attacking the copper.

Label each wire in alphanumeric order right across the fuse box where
letter = fuse position (a =1 b=2 etc)
number = upper (odd)or lower (even) terminal
(piggyback terminals just double digit 22 or 55 or whatever).

Take the fuse box out and yes, clean each spade and each fuse end with 800 grit sand paper.
DeOx gel each spade and fuse end. As you reinstall wires, smear the DeOx gel tracks on the females.

Now you get the delicious opportunity to re-route wires logically. I did this with the BobD after removing the dash panel.

Image

All brown grounds were placed at a similar elevation, all blue indicator/warning lamp wires were grouped to the main harness going back to the engine, all illumination wires (grey-red) were run along the top, and there were countless un-knots required. What does it say that I enjoyed this operation.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

User avatar
satchmo
Old School!
Location: Crosby, MN
Status: Offline

Re: Fuse box corrosion

Post by satchmo » Sun Jan 06, 2013 12:44 pm

Where does one get this DeOx gel of which you speak? I have never seen it in any FLAPS. I've only seen the dielectric tune-up grease by Permatex.

Tim
By three methods we may learn wisdom:
First, by reflection, which is noblest;
second, by immitation, which is easiest;
and third, by experience, which is bitterest. -Confucius

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Fuse box corrosion

Post by Amskeptic » Sun Jan 06, 2013 2:16 pm

satchmo wrote:Where does one get this DeOx gel of which you speak? I have never seen it in any FLAPS. I've only seen the dielectric tune-up grease by Permatex.

Tim
Yes . . . dielectric grease.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

User avatar
hambone
Post-Industrial Non-Secular Mennonite
Location: Portland, Ore.
Status: Offline

Re: Fuse box corrosion

Post by hambone » Sun Jan 06, 2013 9:32 pm

I have seen old de-ox jell bonding with centuries of dust and droppings and acting as an insulator.
http://greencascadia.blogspot.com
http://pdxvolksfolks.blogspot.com
it balances on your head just like a mattress balances on a bottle of wine
your brand new leopard skin pillbox hat

User avatar
satchmo
Old School!
Location: Crosby, MN
Status: Offline

Re: Fuse box corrosion

Post by satchmo » Sun Jan 20, 2013 8:41 pm

I got the corroded fuse box changed out and all the electrical gremlins are resolving slowly. The replacement AFM needed to be exercised, so I took a trip to Joshua Tree National Park for a little desert biking - a new sport I just invented. Range is limited by the amount of spare inner tubes one must carry on account of all the cactus spines you roll over. Anyway, the new-to-me AFM worked well with none of the hiccuping I had near San Fransisco. I thought my CHTs were a little high (400* cruising at 3500 rpm), so I made things a little richer on the dynamic adjustment, which helped the CHT, but I got only 14.4 mpg on my way home. So more adjustment will be done soon.

The fast idle on cold starts has disappeared as well, for no reason that I can identify. I know the AAR is working as it should with lots of vacuum pull at start-up then going to almost no air passing after a few minutes. I tried two different Temp II sensors and that didn't help either. The Bentley says the Temp II should be 2500 ohms when grounded at the connector, but they don't say at what temperature the reading should be taken. I imagine that makes a difference, right? I got over 4000 ohms when I first checked it this morning and then later in the day I had a reading closer to 3000 ohms. Neither Temp II sensor I installed seems in spec but maybe I wasn't taking the reading at 75* ambient if that is what is necessary.

I was by myself camping at Joshua Tree. Not many other people there who would take any time to step out of their RVs and brave the cold. Each morning, however, I would awaken and find this face staring at me:

Image

I started calling him "Wilson" and we had some interesting conversations.

I nearly froze my arse off at Joshua Tree. It gets really cold when the sun goes down. Sweatshirt, down jacket and two sleeping bags were needed to keep me from shivering. I must be getting hypothermic as I age. There is no wood available in the desert for a decent fire, at least not within a half mile radius of the campground at which I was located (Jumbo Rocks). You aren't supposed to pick up any dead plant material in the National Park anyway. I made a fire one night with sticks I had in the bus and a little log I walked about a mile to find. Don't tell Mr. Ranger.

Image

Tim
78 Westy
By three methods we may learn wisdom:
First, by reflection, which is noblest;
second, by immitation, which is easiest;
and third, by experience, which is bitterest. -Confucius

User avatar
Elwood
IAC Addict!
Location: So Cal
Status: Offline

Re: Fuse box corrosion

Post by Elwood » Sun Jan 20, 2013 9:16 pm

Love the face !!!! and was thinking about you in JT--- great place !

Was freezing cold in my cabin--- all pipes froze for 4days , forgot some of my survivor skills to get water. Had to drain hotwater heater on 5th day.

thanks for sharring.
'69 weekender ~ Elwood

User avatar
ruckman101
Lord God King Bwana
Location: Up next to a volcano.
Contact:
Status: Offline

Re: Fuse box corrosion

Post by ruckman101 » Mon Jan 21, 2013 3:34 pm

Corrosion on my fuse box has been from the windshield leaking and dripping onto it. But that's pretty easy to spot.


neal
The slipper has no teeth.

Post Reply