Bussman barrel fuses, BUSS 125V FM01 5A

[mccdeuce]

Please ignore me.... they are all 5 amp.... one just says FM01A   5A.

[Bryan]

Sorry to bring up an old thread but did a (short) flight last night without instrument lights.  I had glareshield lights but the other knob did nothing for my instrumentation.  In reading, searching, and sifting thru the service manual, it appears the easiest thing for me to try is to change out the Bussmann Barrel fuse located (under the panel near the rheostat knobs?)  I have a (new to me) '98 M20K Encore.

Based on this thread, I ordered a couple of [GMW-5 - Fuse, PCB Leaded, 5 A, 125 VAC, GMW Series, Fast Acting] fuses from newark.

My question is, is there a visual indication when these fuses are blown?  Obviously, I could breakout the volt/amp meter but curious if you can see something visually.  I will start with the fuse, and then maybe the CB, and then the rheostat.

[DonMuncy]

No!

[jaylw314]

1 hour ago, Bryan said:

Sorry to bring up an old thread but did a (short) flight last night without instrument lights.  I had glareshield lights but the other knob did nothing for my instrumentation.  In reading, searching, and sifting thru the service manual, it appears the easiest thing for me to try is to change out the Bussmann Barrel fuse located (under the panel near the rheostat knobs?)  I have a (new to me) '98 M20K Encore.

Based on this thread, I ordered a couple of [GMW-5 - Fuse, PCB Leaded, 5 A, 125 VAC, GMW Series, Fast Acting] fuses from newark.

My question is, is there a visual indication when these fuses are blown?  Obviously, I could breakout the volt/amp meter but curious if you can see something visually.  I will start with the fuse, and then maybe the CB, and then the rheostat.

If you pull out the there is a yellow clear plastic top.  I THINK you can see the fuse element in this and whether it is burnt out, but quite honestly, my vision is not good enough to see.   You might need a microscope...

[Bryan]

Okay, so got the Bussman fuses in - they are 5A but them went up-under & behind my panel today to find where they were but could not find them.  Ended up pulling this "Lighting Control" (pictured) out of the panel which houses the two rheostats.  The rheostat on the left is my glareshield lights and the one on the right is my instrument panel lights - not working.

I have two circuit breaks for these two, each at 7½ AMP CB.  Pulling them and resetting did not trigger the panel lights at all - hoping maybe it was stuck.

Maybe the newer (1998) doesn't have the in-line fuses?  Strange that the fuses would be at 5A and the CB at 7.5A.  If I new how to test the rheostats - that might be next, checking that now.  I guess I could check the CB, too. Unless someone has some other ideas, I might give a MSC a call next week.

1998 M20K Encore (25-2026)

[Cardinal767]

On 9/22/2017 at 2:15 PM, mccdeuce said:

Ok - bringing this back to life hopefully you guys can fix my stupidity....

I blew the radio light fuse.  While working this I decided to remove all 4 of my bussman fuses that are down there.  Thinking they were all 5 amp....  They were not.  And I don't know which one goes where....  and of course they are not labeled with their amperage.

My schematic is for a 78 J but not my specific serial number and I believe it shows only the two 5 amp fuses.

Anyone know?

The spots are BUS  BATT RADIO  INSTR    

Look at your schematic. Find your SHUNT. It is still in the same section(CIRCUIT BREAKER PANEL) as the other two fuses. You’ll see a BUS and BATT fuses coming off the SHUNT and are going to your amp meter, that’s your other 2 fuses, amp sizes are shown. My 81’ K has a total of 4 each 5 amp fuses. The INST, powers the glare shield and FLAP/TRIM indicators. The RADIO, powers my radio and instrument back lights and a few post lights. I just put in a new radio and transponder and blew a fuse.