Pat McGriff

Good evening,

I'm in the process of replacing the engine wiring harness on my 69 big block. I've read a number of threads on here outlining this process, including loosening the 3/8" bolt, pulling, and repeating. I've been at it for a few hours and nothing seems to be happening. I tried from under the car, and have now removed the brake booster to get at it from above. I've been able to pry the edges of the engine side connector away, but the bolt in the center of the connector doesn't want to do anything but spin (I understand it is captured and does not come out of the connector).

Any advice from someone who's had a similar battle......and won? I appreciate the help.

caskiguy

Pat, If the center screw is turning with no results, maybe can you wedge a screw driver (something flat) between the firewall and the wiring bulk head on the side to create upward pressure and turn the center bolt at the same time ? If all else fails drill numerous holes in it and remove it bit by bit, its brittle plastic and should crack easily.
Don't get to crazy a the firewall is pretty thin and you may damage it.
Taking things apart on these cars after 45-50 years can be a trick.
Good luck.

CanadaGrant

I replaced the engine harness on my 69 BB last year. I removed and installed the block from underneath without removing anything else except the lower bolt-on panel between the frame and fender but yours is a different story. I think Caskiguy is correct and the caged nut on the other side of the assembly is turning. Since you are replacing the harness and already have the booster off for access I would use a dremel tool with a cut off wheel on the engine side, cut into it and remove the small 3/8" head off the hold down bolt to slide the harness block off. The new harness block should come with a new fastener. Then you can see if the enclosed nut is turning, maybe stick something in there to hold it while you turn the bolt out or whatever you have to do to then JB weld the nut to prevent it from turning and doing it again.

Pat McGriff

Thanks for the advice! After prying and prodding, I took the drill approach and got the lighting harness out ( wanted that one out of harm'sway)

, then drilled off the head of the bolt holding the harness to the fuse block . What a PITA. Epoxying the captured nut back in its home in the fuse block.

caskiguy

That a boy !

CanadaGrant

Once your brake booster and everything else is back on, if you need to do anything with that harness just remove the 3 bolts on the triangle (sorta triangle) shaped weathershield that is between and bolted to the frame, the inner and the outer fender. It comes off from underneath and you then have access to the 2 parts of the fuse block and everything else in that area from the under side.
Glad it worked out for you!