Lamp type

[OkieAviator]

Dome light isn't working in the plane so I wanted to swap the bulb before I get an A&P involved. If it's the bulb I'll see if he'll sign the swap out. The bulb I pulled out is a GE 94 LG. However Aircraft Spruces bulb chart shows that's the wing and tail light and the dome is supposed to be a 313. I checked the manual and all I get is that it's a 'Lamp'. Found another table that talks about amp minimums.

Anyone know what bulb type goes in a 1977 172N?

 

[bnt83]

Dome light isn't working in the plane so I wanted to swap the bulb before I get an A&P involved. If it's the bulb I'll see if he'll sign the swap out. The bulb I pulled out is a GE 94 LG. However Aircraft Spruces bulb chart shows that's the wing and tail light and the dome is supposed to be a 313. I checked the manual and all I get is that it's a 'Lamp'. Found another table that talks about amp minimums.

Anyone know what bulb type goes in a 1977 172N?

electrical Stuff can be hard to distinguish in old Cessna manuals. One good shot is looking through wiring diagrams in the very back of the Service Manual. Otherwise you need a Parts Manual.

There was an AD on overhead lights but not sure that it applied to the 172N. The dimmer up there was catching fire on certain models...

 

[Stewartb]

NAPA know how!

 

[flyingron]

I suspect you're running afoul of the fact that the 172N is the model where they switched between the 12V and the 24V electrical systems. Yours being a 1977 is probably a 12V system. The 313 is a 28V bulb and has a miniature single contact bayonet (typical pilot light) base. The 94 is a dual contact 12V bulb with a larger dual contact base (essentially an automotive tail light).

Make sure you're using the replacement chart and documentation for your PARTICULAR instance of the 172N.

An owner/pilot doesn't need a mechanic to sign off a bulb change. You can do it your self (but you must log it).

 

[bnt83]

Dome light isn't working in the plane so I wanted to swap the bulb before I get an A&P involved. If it's the bulb I'll see if he'll sign the swap out. The bulb I pulled out is a GE 94 LG. However Aircraft Spruces bulb chart shows that's the wing and tail light and the dome is supposed to be a 313. I checked the manual and all I get is that it's a 'Lamp'. Found another table that talks about amp minimums.

Anyone know what bulb type goes in a 1977 172N?

I pulled up a 172/175 Parts Manual and it shows MS15584-2 which is a GE94. (This manual does not cover your year.)

Your screen shot is a Service Manual.

 

[OkieAviator]

So chances are the GE 94 I pulled out was the correct one? As Ron stated it's a dual contact vs the single contact.

I'll see if I can find a parts manual as well. Thanks!

 

[Jeff Oslick]

NAPA know how!

 

[Jeff Oslick]

There was an AD on overhead lights but not sure that it applied to the 172N. The dimmer up there was catching fire on certain models...

I would sure hope every plane involved in that AD has had that covered already. That ranked pretty high in the "could cause a really bad day" category. I think (IIRC) the issue was the dimmer pot on the lower instrument panel, not in the overhead.

 

[bnt83]

I would sure hope every plane involved in that AD has had that covered already. That ranked pretty high in the "could cause a really bad day" category. I think (IIRC) the issue was the dimmer pot on the lower instrument panel, not in the overhead.

I get that Jeff but one-time ADs get ignored and careleess maintence can cause basically the same issues to reoccur like firewall valve issues have brought down post AD Cardinals.

Putting a wrong bulb in something can cause fires.

 

[Mike Smith]

You can buy a 94 bulb at any auto parts store, should by around 3 bucks.

 

[OkieAviator]

You can buy a 94 bulb at any auto parts store, should by around 3 bucks.

I ran by O'reilly's and Autozone and none had the exact match. They could all order it though or had it in a warehouse somewhere. I had to order some more paint from Amazon so I just added a bulb on there for $5.

 

[bnt83]

I ran by O'reilly's and Autozone and none had the exact match. They could all order it though or had it in a warehouse somewhere. I had to order some more paint from Amazon so I just added a bulb on there for $5.

GE94 probably hasn't been used in cars since the 1970s so I think its getting harder to find locally.