Fuse type for 56 radio?

[56 Buick]

Hi, so I bought the car knowing the radio didn't work but I see the fuse tube for the radio has no fuse in it.

 

The shop manual states the fuse should be a 7.5 amp special fuse. But what does 'special' actually mean? If it takes a glass fuse then they would have stated AGC?

 

Thanks

 

Drew

 

[EmTee]

Does it require a slow-blow fuse?

 

https://www.bentronics.com/14x114-glass-slow-blow-mdl-c-16_85_1154_87_662_131/75-amp-mdl-glass-fuse-2pk-slow-blow-14x114-p-457.html

 

[Rooster]

Possibly means it's a shorter fuse than the standard length.

[old-tank]

Save yourself some grief and splice in a fuse holder for the more readily available (and dependable) blade fuses...no one will see it!

Those old glass fuses are by now coming apart due to the cement giving up.  The 'new' replacements from the Pacific Rim are sometimes DOA or will not handle the rated amps.

[Beemon]

I've personally never had issue with glass fuses.

 

Why do you want to hook up the radio if it doesn't work?

[Guest]

Maybe it did not work because there was no fuse in the line.

[Bloo]

Glass fuses are the worst....

 

But if it is an inline fuseholder there is much less chance of trouble than if it were in a fusebox.. In that case I would leave it alone, particularly if original. It probably takes a slow blow fuse, due to the current inrush caused by cold tube filaments. If you can figure out what size fuse phycially fits in there (standard AGC, SFE, or 5mm metric or whatever), and measure it, we can probably figure out what the number is for a 7.5 amp slow blow. If the automotive suppliers don't have it, Newark, Mouser, or DIgi-Key will.

 

The constant glass fuse failures aren't really the fuse's fault. It is the fusebox. Some sort of springy metal is used for the clips, probably stainless but I'm not certain. Whatever it is, it will not solder. These clips are generally riveted on, and after some years the connection degrades due to corrosion. The rivet then gets really hot, The heat telegraphs up the clip into the glass fuse melting the solder inside. It also melts the hot glue that is holding the fuse end cap on. The air inside the fuse expands from the heat, pushing the end cap off just enough that the fuse element inside no longer touches the pool of solder. Then, everything cools back down. The fuse will look fine but will not work anymore. If you look at it really closely you will see a little bit of glue on the glass where the end cap slid. Hold it up against a new fuse, and it will be a tiny bit longer.

Edited June 4, 2018 by Bloo (see edit history)

[56 Buick]

Thanks for the help guys. I knew the radio was not working when I bought the car but I did not know why and perhaps there being no fuse is the reason why. Gotta get lucky sometimes :-).

[Beemon]

If the vibrator is not audible, turn the radio off and send it out. If the vibrator comes on but there's no sound, definitely turn it off and send it out. 

[Ben Bruce aka First Born]

6 hours ago, Beemon said:

If the vibrator is not audible, turn the radio off and send it out. If the vibrator comes on but there's no sound, definitely turn it off and send it out. 

 

  Words from the wise!

 

  Ben