140 Restoration - Filter Caps ground question

[jerrycpor]

In the middle of a restore on this 140 amp and am trudging through the replacement of the single dual can with a pair Chemi-Cons.

I discovered a way to use the original ground strap, if it can be attached to the screw holding the rectifier to its heatsink. The screw is verified ground, and goes through the heatsink with enough protruding to fasten the strap to it using a star washer and nut.

I just want to double check that it can be safely tied to ground there without any issues??

Attached is are images with an arrow indicating where I'm thinking of tying into.

Jerry

 

[catrafter]

That should work, IF the connections between the ground strap, the rectifier heat sink, and the chassis are all shiny and tight.
Keep in mind that the heat sink may be an aluminum alloy.

Here's another way to do it, YMMV.

Tom

 

[jerrycpor]

Thanks Tom.

The ground continuity will be mostly made with the screw itself, the internal threads in the heatsink, and then the star washer and nut holding the strap. Just the same, I will be sure all is clean and shiny. When you mention that the heatsink may be an aluminum alloy, are you thinking of an issue with dissimilar metals?

Thanks again,
Jerry

 

[jerrycpor]

Your installation looks pretty clean I might add.

 

[catrafter]

It may be difficult to keep the screws tight as aluminum is soft. I hadn't thought about galvanic corrosion, but that could be a consideration too, especially near the ocean.

Tom

 

[jerrycpor]

Okay, gotcha, thanks Tom

I think it'll be good. The screw threads into and through the heatsink...tightly. Then, on the remainder of the threads poking through, the ground strap is fastened with a star washer and nut. It's really more like a threaded stud that the ground strap is secured to.

Still have to put in a couple black zip ties to neaten up some wires, but here's the end result.

Thanks again!
Jerry

 

[catrafter]

Nice!