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1965 Honda CP77 — Ulsan Metro City, Rep. Korea
Restored with original parts — Owner: J. Doe

CA77 Starter relay

Charging System, Wiring, Lighting
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Nick
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CA77 Starter relay

Post by Nick » Fri Oct 31, 2025 5:50 pm

Anyone ever rebuild one? Mine still makes the requisite clicking sound when power is applied, but it hasn't been used in anger in at least 15 years.
Do what you've always done and you'll get what you've always had.

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Tim Allman
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Re: CA77 Starter relay

Post by Tim Allman » Mon Nov 03, 2025 12:09 pm

I've rebuilt a few CB77 relays but have no experience with CA77s but I suspect they are either similar or identical. Here are a few comments.

First, is your battery in good condition and charged? This is a requirement for the starter to work. If you need to, a 12V car battery or portable jumper will work. If the starter works the all you need to deal with is the battery.

Otherwise,

Remove the large cables from the relay.
Remove the small screws on the cover and remove the cap from the body. The fact that you are hearing the clicking tells me that the magnetic coil in the main body is fine so you don't need to do anything with it.
You can see the two contacts on the inside of the cap and the copper bar that closes the contact to run the starter.
Both contacts and the bar probably all need cleaning. Steel wool works well.
If you remove the two contacts be sure to keep track of the order of the steel and fibre washers so that they can be reinstalled properly.
Reassemble after cleaning.

Otherwise,

If this doesn't work then you may have a starter motor problem, either at the terminal where the cable connects or inside but I think that is less likely.

Good luck.

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Muddy
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Re: CA77 Starter relay

Post by Muddy » Mon Nov 03, 2025 6:24 pm

I agree with Tim. Address the battery first - make sure it is fully charged and reliable. As Tim suggested, use an alternate known-good battery as a check.

It could be the starter relay, but more likely the battery.
Thanks.

Regards

Muddy

'64 C72
'63 C72

Nick
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Joined: Thu Oct 15, 2009 2:03 am
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Re: CA77 Starter relay

Post by Nick » Wed Nov 19, 2025 6:37 pm

Thanks for all the info. Actually, it was working but I was just curious what all was involved. Took it apart the other day and everything was in very good condition, remarkable considering how old it is.
If I could ask another favor.... do you or anyone you know have any Dream petcock parts? Specifically, the the top washer with the little compression spring and, if possible, the two round rubber discs with the fuel holes. I can probably reuse the two round discs but absolutely need the top one with spring.
No suppliers have those parts so I may have to bodge something, so any tips in that direction would also be appreciated.
Do what you've always done and you'll get what you've always had.

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