Author Topic: Cleaning my Bulkhead Connector.  (Read 17408 times)

Offline Spool

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Cleaning my Bulkhead Connector.
« on: January 25, 2018, 06:49:06 PM »
Hey guys,

73' C20 here.

I'd like to clean my Bulkhead connector.
I've removed my fuse panel from the bulkhead, but does the bulkhead separate in two pieces so that I may clean it without a firewall in my way?

Pictures attached.

Thank you.

Online bd

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Re: Cleaning my Bulkhead Connector.
« Reply #1 on: January 25, 2018, 10:10:26 PM »
There is no need to separate the fusebox from the bulkhead or the bulkhead from the firewall unless you are replacing wires that connect to the bulkhead inside the cab.  Removing the center screw from the outside as you have will allow you to unplug the engine compartment side of the connector from the firewall bulkhead.  Why are you cleaning the bulkhead connector?
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Spool

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Re: Cleaning my Bulkhead Connector.
« Reply #2 on: January 25, 2018, 10:22:53 PM »
I don't seem to see the capability of disconnecting the bulkhead on the engine side; is there a tab or screw I'm not seeing?

I'd like to to have the engine side free so that I may spray cleaner inside of it, clean it out, and let it air dry so that I can pull out the gunk and replace the connection on ckt 3.

Offline ehjorten

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Re: Cleaning my Bulkhead Connector.
« Reply #3 on: January 26, 2018, 10:37:54 AM »
When you removed that center screw on the engine side of the bulkhead connector, it should have stayed connected to the engine side connector and pushed the connector off of the bulkhead.  With that screw removed, you should just be able to pull the engine side of the connector off of the bulkhead.
-Erik-
1991 V3500 - Gen V TBI 454, 4L80E, NP205, 14 bolt FF, D60, 8" Lift on 35s
1977 K20 Silverado - 350, THM350, NP203, 14 bolt FF, D44, Stock Lift on 31s
1969 Chevelle Malibu Sport Coupe - EFI350, THM350
1968 Chevrolet Step-side Pickup - 300HP L6

Offline Spool

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Re: Cleaning my Bulkhead Connector.
« Reply #4 on: January 28, 2018, 12:10:23 AM »
This is what I was hoping to do, but I can't seem to separate the two.
I also couldn't see well enough to fully observe it.

What type of connection holds the 'engine side bulkhead connector' to the 'interior side fuse panel'?
Should I be able to simply pull them apart?


My primary objective is to replace ckt 3 on my bulkhead connector.
I attempting to see the otherside of the bulkhead connector before cleaning and removing the existing wire. (If it's possible to do so.)

Online bd

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Re: Cleaning my Bulkhead Connector.
« Reply #5 on: January 29, 2018, 12:40:27 AM »


The center-bolt (red circle in image) retains the engine harness connector to the firewall bulkhead socket.  Generally, an e-clip locks the center-bolt into the engine harness connector such that unscrewing the center-bolt dislodges the harness connector from the firewall bulkhead and separates the two along their seam (yellow line in image).  The harness connector is a very snug fit into the bulkhead, because of the number of press-fit electrical terminals and the tacky antioxidant "gluing" the connector halves together.  You may have to work at it by wiggling the engine harness connector side-to-side and up-and-down while pulling hard.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Spool

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Re: Cleaning my Bulkhead Connector.
« Reply #6 on: January 29, 2018, 03:08:41 PM »
That was exactly the case.
A general rule of thumb I have in the camera/production world, is if you have to force it than you're doing it wrong.
However, after close examination I saw one corner of the engine side bulk head connector was coming apart.
With a little help of a flathead screwdriver I was able to peel them apart.

What I found inside was horrific. I'm in the process of cleaning this out now.
Any tips?

Is it possible to just order a new one to start clean?

Online bd

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Re: Cleaning my Bulkhead Connector.
« Reply #7 on: January 29, 2018, 04:38:30 PM »
The bulkhead connectors, if available at all, are serviced only as part of a replacement wiring harness.  The tacky black gunk is an antioxidant/sealer that helps seal out moisture and contaminants.  Don't let it concern you.  The area of concern is the muddy half of the connector.  Water and dirt have intruded that side, which can lead to corrosion.  It appears the bulkhead connector gasket deteriorated and someone did a poor job of substituting red silicone sealer.  You can make a new gasket with some 1/8" closed-cell foam rubber, an Exacto knife and a lot of patience. 

To prepare the bulkhead for reassembly, spray the terminal side of the connector liberally with aerosol carburetor cleaner and scrub using a nylon bristle brush to remove the dirt and dried gunk.  An old toothbrush may work for this purpose.  Blow the connectors and terminals dry with compressed air.  Make sure there is no greenish corrosion on any of the terminals then pack the connector cavities and terminals with Truck-Lite NYK-77 Corrosion Preventive Compound (#97944).  Pick up a couple of tubes - you will use it a lot in electrical repairs.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Spool

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Re: Cleaning my Bulkhead Connector.
« Reply #8 on: February 01, 2018, 10:27:38 PM »
I personally can't stand dirty environments, especially if I'm fixing something.
With that, I labeled all my wires, disconnected them and deep cleaned my bulkhead connector on the engine and passenger side.

I used Carburetor Cleaner, wire brushes, sand paper and tooth picks while exercising extreme caution not to leave any remnants of wire brush or wooden toothpicks behind.
Pictures are attached of the job.
(I also fell in love with carburetor cleaner. It allowed me to clean my wires to almost new condition, revealing their original color.)

Truck-Lite compound is on the way.
I'd like to ask, is it best to insert the terminal into the connection before or after applying the corrosion preventive compound?

I researched the difference between open and closed cell foam after your recommend of using a closed cell foam as a gasket.
However, my concern is that I'd rather not seal it at the moment considering many of my wires need repair and I would like
easy access to my bulkhead. Living in Los Angeles, which has very little rain, yet occasional dewy mornings, do you think I can get away with holding off for now?

Offline Spool

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Re: Cleaning my Bulkhead Connector.
« Reply #9 on: February 04, 2018, 06:36:42 PM »
Pictures of the bulkhead re-wired after cleaning.

Corrosion Preventive Compound still on the way in the mail.

Online bd

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Re: Cleaning my Bulkhead Connector.
« Reply #10 on: February 06, 2018, 08:29:58 PM »
Looks sharp!  Be sure to pack the area between the connectors and all of the cavities with NYK to fill all of the voids and repel moisture and dust.  It will be messy.  Initially, the antioxidant will be very creamy similar to a low viscosity white grease.  As time passes (several weeks to a few months), it will gradually thicken.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Spool

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Re: Cleaning my Bulkhead Connector.
« Reply #11 on: February 07, 2018, 10:14:42 PM »
Thank You!

The NYK arrived today.
Knowing it will expand the way it does, would you have any tips on applying it?

Aesthetically, I'm currently thinking I can fill each cavity a few millimeters away from the surface of the bulkhead,
so that the compound will sit flush with the surface of the bulkhead after it expands.
Do you think that is a good approach?


Online bd

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Re: Cleaning my Bulkhead Connector.
« Reply #12 on: February 08, 2018, 08:34:01 AM »
NYK doesn't expand, it becomes more viscous.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Spool

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Re: Cleaning my Bulkhead Connector.
« Reply #13 on: February 08, 2018, 12:05:52 PM »
I had misunderstood 'thicken over time' as a way of expanding.
(Specifically because the last job done, that I had just cleaned out, was far outside of the cavity itself.) I was assuming that was why it was everywhere.

With that, I'll just keep it clean and apply it up to the surface of the bulkhead connector.

Thanks again!