Door and Harmonica Connector - 10/15/2006

Since the steering column was replaced with a 1978 model and GM changed the harmonica connector between 1975 and 1978, I had to get the spade connectors from one plug into another. At the same time it can't be safe to have a door that doesn't open and close properly, so the door latch needed to be fixed.

The latch has been dipped in the parts cleaner for quite a while. The lever in the hole on the far left side of the latch was not moving at all, preventing the striker bar from staying latched. Lots of PB Blaster and gentle movements cleared this up.

Not perfect, but I don't want to spend $65 for a new one.

The side that is exposed to the door.

The inside of a '75 Firebird, with all latch guts removed. Notice the funky rot near the door jam switch. I've never seen a car rust\rot out here. It's really bizarre. These doors are wasted and probably should just be replaced. The seams along the bottom are full of mud and dirt and most are broken so that dirt and mud tries to fall right out.

The latch area.

All of the innards for the latch mechanisms.

We had a problem. The door wouldn't open once the hardware was placed back in. It would just rattle around. So Houston, we have a problem. The door closes, but the bonus of it not opening back up makes it quite an unpleasant trade off. We had to remove the striker bolt with a Torx bit (from INSIDE the door with the door closed) to get the door to open. At least The General designed it so you could get the striker bolt from inside the door with the door closed... It doesn't show well but someone used a pair of channel locks or a pipe wrench on this bolt, so it was quite knurled. Proper tools people!

Striker bolt removed. Striker was obviously added to the body BEFORE paint.

A 1969 Tempest uses the same striker bolt, but uses a 5/16 Alan wrench bit instead of Torx (not sure why). We removed this from a parts car since the original was quite nasty and we were unsure of whether the striker bolt was the source of the problem or not.

Striker bolt all nice and wire-wheeled clean.

Striker bolt is installed.

At least the backing brace is caged to prevent it from falling...

2.5 frustrating hours later and the door opens and closes as perfectly as one can expect from a 30 year clapped out Trans Am. Door sags slightly, but that will be remedied later.

All innards are installed.

This nylon guide piece was the source of ALL of our door problems. This nylon piece is supposed to guide the striker latch and keep it straight, likely serving as an anti-rattle mechanism. Well, unfortunately for us the nylon piece is supposed to be almost as long as the drive bolt holding it in. This was not. So the latch would hang up and get caught when the nylon piece twisted around. This is definitely NOT a serviceable part, so the only solution is to drive it out or replace it with a new one. I don't know how many Trans Ams out there have stuck doors, but this can definitely be a source of problems for them opening and closing. And it's SO much fun to do this with the door stuck CLOSED...

Now that this piece of drama was over with I could move on to the next bit, the harmonica connector on the steering column. Using a dental pick, the spade connectors can be removed from one and transfered over to the other! 1973 and 1978 wiring diagrams show the exact same order for all of the wires on each plug, so I doubt it would be much issue other than changing the connectors over!

The old spades from the harmonica connector are removed.

1975 harmonica connector, steering column piece.

Close, but definitely different. No idea why this was changed honestly... Total number of pins available and pins themselves didn't change.

Spades are transfered over in the same order.

And connector is plugged back in and tucked under the column. Just like nature intended!

Lookee here! A Camaro! A 1978 car with no AC (and really no other options either).

Yay! 305 2bbl with all of the smog equipment! Disc brakes and subframe are all in good shape (maybe, it stops pretty nicely).

Hard to tell from the photo, but it's burning a fairly good amount of oil.

Green interior... Seat is stuck halfway up, so my knees bang the dash as I drive it. Heater controls are disconnected like someone was trying to get them out but got bored halfway through... Fan still blows but not out the defrost OR the heater ducts, so no real clue there. Original Delco AM radio still included (doesn't work). As a matter of fact, none of the dash lights or gauges seem to work except the idiot lights and the speedometer. The gas gauge ticks up and down around 3/4, so no telling much gas is in it. Forest green fur headliner is a bonus.

The car is free provided I pull the motor and transmission out for Dana. No worries there, at least it runs and drives. I feel kind of bad about purposefully gimping a car that isn't rusty or rotten and still runs and drives, but it's just a Chevy, so I don't feel too bad about it. Not too many parts interchange, but there is plenty of good sheet metal to fix the handful rusty\rotten parts on the '75 and the mirrors are in great shape compared to the complete lack of mirrors on the '75. The hood and A-pillars are good on this car, which is a plus since someone put putty\silicon in the windshield channel of the '75, making me scared to find out what is lurking down below...

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Last updated October 15th, 2006