1970 510 white needle tack issue

[Hurley]

Looking for some help. I bought a used factory tack for my 510. Installed it yesterday and drove for a short time and it was working well.

Went for a longer drive this morning and the needle slowly began to rise until it pegged. I shut it off for a bit and then fired it up again and it was fine for a few minutes then it began to rise again. Any help would be appreciated.

Thanks! Brian

[jefe de jefes]

I had issues with mine so I ended up doing this.

Hope it helps.

 

 

http://community.ratsun.net/topic/33291-510-tachometer-fix/

[spottedog]

Probably "puffy caps". No, I am not pulling your chain, electrolytic capacitors common in all electronic devices, contain a gelled acid which will leak when they get old.

(they sometimes actually explode making the bad one easier to find)

 

Do whatever to expose the circuit board, electrolytic capacitors look like small cans with partial metal tops. The round metal top should be flat, not puffed up at all.

 

If you see a bad one unsolder it from the board, and look at the printing on the can and write it down.  For example,  '"16v or 16wv" means 16 volts maximum,

the next line will read something like "20 mfd" or something similar.

 

Put the bad one in your pocket and go to a Radio Shack store and buy a new one for a couple of bucks.

 

LOTS of electronic gear gets thrown out just because it has a bad cap (puffy cap) you can get for $1.50 or so.

 

This fix also applies  to vintage Ratsun radios.

 

[Hurley]

Probably "puffy caps". No, I am not pulling your chain, electrolytic capacitors common in all electronic devices, contain a gelled acid which will leak when they get old.

(they sometimes actually explode making the bad one easier to find)

 

Do whatever to expose the circuit board, electrolytic capacitors look like small cans with partial metal tops. The round metal top should be flat, not puffed up at all.

 

If you see a bad one unsolder it from the board, and look at the printing on the can and write it down.  For example,  '"16v or 16wv" means 16 volts maximum,

the next line will read something like "20 mfd" or something similar.

 

 

Put the bad one in your pocket and go to a Radio Shack store and buy a new one for a couple of bucks.

 

LOTS of electronic gear gets thrown out just because it has a bad cap (puffy cap) you can get for $1.50 or so.

 

This fix also applies  to vintage Ratsun radios.

Thanks! I'll check it out.

[MikeRL411]

If the capacitor is/are bad, instead of unsoldering from the PC Board try this.  Clip the leads close to the capacitor body and straighten them out vertically to the board.  Take the new capacitor and neatly twist the leads to the two wires you just straightened out and solder them together with due regard for polarity, slip a shrink fit tube over the soldered wires, obviously heat shrink the tubes, and dress them close to the PC Board [that's why you insulated the soldered joints, so they would not short to any other component.]  This puts much less stress on the solder joint to the PC Board, and is a "standard" repair method.  You can't really trust the through [via] holes on a 33 year printed circuit board.  They will delaminate and break connection with too much heat.  They will look fine but will have no continuity through to the other side circuit leads.  Good Luck!