1956 Power Top Limit Switch Mechanicals

[Richard M.]

Re: 1956 Power Top Limit Switch Mechanicals

Here are the relays and wiring. It's simply splitting the solenoid load wire out of the switch circuit and into the relays which are controlled by the 4 normal limit and safety switch paths. I chose to source the feed for the relays from the Dash Switch #12 Red tap for the pump motor. This keeps the feed wire in the trunk unpowered, and only live when the Power Top function is used. I also installed a 20A inline fuse at the dash switch tap point. The relays(with mount tabs) mounted easily to each solenoid cover corner using the existing screw holes. Using 90* terminals, I was able to keep the modification rearward height covered up with the stock bulged division panel. This would keep the modification unobtrusive if the car is being judged.

BTW, each relay coil draws about 170 mA (0.170 A). Each solenoid draws about 15 amps. Since all of the solenoid load current now passes through the relay switch contacts, the electrical system will never get hot as it did before, and all of those rare switch contacts will breathe much easier.


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While I was at it I also rebuilt the Dash Power Switch.
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With all rebuilt switches, restored/repaired wiring and all terminals, rebuilt motor, pump, valves, and solenoids, along with added fuse and solenoid relay protection, this power top system will hopefully last a long time.

Rich

[Dan D.]

Re: 1956 Power Top Limit Switch Mechanicals

Hi Rich, very nice, and a very good idea.

As a side note, what did you use to clean the brass contacts and copper rivets on the switch? I can clean copper quite well with vinegar or with off the shelf type kitchen cleaners found in most grocery stores, but I have not found anything that will clean brass, and your switch sure looks nice.

-Dan-

[Richard M.]

Re: 1956 Power Top Limit Switch Mechanicals

Dan,

I start with a fine wire brush to get the heavy dirt off, then finish with my trick eraser. It even gets under and between the rivets and blades. It's made for cleaning electrical contacts like brass, copper and gold without damage. I've used these for years. They also work for chrome & stainless. If you ever had light pitting on small chrome or stainless trims, the eraser even cleans light rust stains without a hint of scratching.

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However, they are pricey. Several years ago I bought a replenishment stock of the Fine Grade refills. And a few of those Red stick erasers. They're a fine tip also, and just peel the plastic away when it wears down.

The Eraser company, Syracuse NY http://www.eraser.com/fybrglass-brushes-and-erasers/

You cannot buy from resellers, direct only. Unless someone else re-sells them now, not sure.

Rich

[Cecil L.]

Re: 1956 Power Top Limit Switch Mechanicals

Great work, as usual Rich.
BTW those erasers look like stick versions of Never-Dull. They would obviously be much easier and more effective than trying to work a wad of Never-Dull into all those tight places with your fingers.

[Richard M.]

Re: 1956 Power Top Limit Switch Mechanicals

Fellow member Dave Zuberer did me a great favor and created a PDF file and documented the CF thread I started when I began work on this top system.

It can be downloaded for future reference from here.....

http://home.comcast.net/~richmz/onlinestorage/Documents/1956PowerTopRestoration_07-11-14.pdf

Edit(3/26/2024)... my Comcast site is gone but look in our Stickey "Database of Restoration Documents" page. It's in there.

Rich

[Richard M.]

Re: 1956 Power Top Limit Switch Mechanicals

Last weekend I got a call from someone with a '56 Power Top problem. We figured out he had a miswire. He fixed it and it works fine now. I decided to create a Operations Sequence document for future diagnosis reference. Dave Zuberer PDF'd it for me.

Attached below. See 1956PowerTopSequenceChart_with diagr.pdf

A new revision of my PT Wiring diagram is also included within the document,

Also attached here separately is the new Wiring Diagram, Rev 4. It's the same as Rev 3 above except I added a few items, no corrections.

Rich

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