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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: richard5933 on September 10, 2019, 11:53:00 AM

Title: GM Dash Light
Post by: richard5933 on September 10, 2019, 11:53:00 AM
Looking for a replacement dash light for my GM 4108. Says "Grimes A7195-1-334" on the barrel. They are about 3/8" in diameter and about 3/4" long and mount through the dash over the switch banks. You can see it in the attached photo at the top of the toggles.

Anyone know of a source for these? Or, anyone have a working light in a parts bus that they can spare?
Title: Re: GM Dash Light
Post by: richard5933 on September 10, 2019, 04:34:21 PM
Discovered today that the lights GMC used for the dash lighting were pulled from the aviation parts catalog. Not sure why they went that route, but perhaps it will help find replacements.

Anyone in the aviation world have any parts suggestions for something like this? Checking on eBay I've found one with the same number, but it had a blue lens and was $400. Not quite what I'm looking for on either account.

Luke is checking his sources, but apparently I'm the first one to have such a light burn out. Figures.
Title: Re: GM Dash Light
Post by: chessie4905 on September 10, 2019, 05:57:01 PM
Are you sure the bulb can't be replaced?  Pull the assy. and check. Let me know how Luke makes out. My conversion has nice chromed domed lamps with illumination slots for bulb output. About 1/2" diameter and about 1 /2" high. If Luke can't help, I could pull two from my parts coach.
Title: Re: GM Dash Light
Post by: richard5933 on September 10, 2019, 06:13:59 PM
Quote from: chessie4905 on September 10, 2019, 05:57:01 PM
Are you sure the bulb can't be replaced?  Pull the assy. and check. Let me know how Luke makes out. My conversion has nice chromed domed lamps with illumination slots for bulb output. About 1/2" diameter and about 1 /2" high. If Luke can't help, I could pull two from my parts coach.

Haven't found a way to get to the bulb yet. I'm thinking that the whole assembly is intended to be replaced, not just the bulb. Waiting to see what Luke can dig up before I attempt to remove the assembly. Luke said this is the first one he's heard of that's gone out. Figures I'd have it happen.

Of course the one that's gone out is the one on the left side, which is more difficult to get access to. Lots more going on under it with the gauge cluster, and it's not nearly as simple as pulling the speedo on the right side. Don't really want to open things up till I know that I have a game plan to move forward.

I found a couple on eBay, but I suspect that they are going to be too big once they arrive. If so, they'll be useful in other places so I didn't mind checking them out.

Would love to find someone that's been inside these Grimes assemblies before.
Title: Re: GM Dash Light
Post by: chessie4905 on September 11, 2019, 04:22:18 AM
Did you try pulling the two screws for the switch panel and moving it aside? the switches and wiring should be more durable to move around with less drama. Maybe it will turn out to be a bad connection.
Title: Re: GM Dash Light
Post by: richard5933 on September 11, 2019, 07:07:15 AM
I got a bit daring this morning and decided to yank on the cover of this lamp. Lo and behold, the cover comes off and there is a bulb underneath that can be removed. Tiniest little bulb I've ever seen. Good thing is that there is still power to the socket, so all I need is a new bulb.

No markings on the bulb other than "USA". Any thoughts on where to find one of these? Or maybe what this type of bulb is called?
Title: Re: GM Dash Light
Post by: richard5933 on September 11, 2019, 07:20:07 AM
Sometimes things surprise me. I stumbled upon the bulb by looking on a few aviation supply websites.

Apparently it's this bulb: GE Incandescent Lamp: 28v | 334 | 28588

They were only $0.61/ea so I ordered a few. Probably never need the others now that I've got them.
Title: Re: GM Dash Light
Post by: pabusnut on September 11, 2019, 08:29:05 AM
Richard,

Can you list the site you bought the bulbs from?
I need some too! 

Thanks!

Steve
Title: Re: GM Dash Light
Post by: richard5933 on September 11, 2019, 08:29:53 AM
https://pilotshq.com/incandescent-lamp-28v-334-28588-p-8907.html
Title: Re: GM Dash Light
Post by: pabusnut on September 11, 2019, 09:58:03 AM
Richard,

Thanks!  I will buy a few extras --somebody may have a need at Blytheville.

Steve
Title: Re: GM Dash Light
Post by: buswarrior on September 11, 2019, 11:07:50 AM
Same or similar in the transits too.

So many busnuts don't drive at night... which came first?

Happy coaching!
Buswarrior
Title: Re: GM Dash Light
Post by: richard5933 on September 11, 2019, 11:10:00 AM
Quote from: pabusnut on September 11, 2019, 09:58:03 AM
Richard,

Thanks!  I will buy a few extras --somebody may have a need at Blytheville.

Steve

Funny, I did the same thing. Figured either I'd need them or someone else would down the road.
Title: Re: GM Dash Light
Post by: chessie4905 on September 11, 2019, 11:53:03 AM
Probably listed in the parts book, along with industry part number.
Title: Re: GM Dash Light
Post by: richard5933 on September 11, 2019, 12:25:49 PM
I found one which might be it on page 7-3 in the parts book (X-172010). It's listed as:

273986      Bulb - drivers switch panel lamp

Parts manual does list it as industry part 334.

Don't know how I missed that - must have looked half a dozen times. Guess I'm not that good with parts books when I'm tired and frustrated.

Regardless, some are on the way.
Title: Re: GM Dash Light
Post by: chessie4905 on September 11, 2019, 03:55:28 PM
Most items are in the parts book.  Finding them sometimes requires advanced sleuthing. Then, in the service manual, where is the fuel tank strap bolt torque specs?
Title: Re: GM Dash Light
Post by: richard5933 on September 11, 2019, 06:30:31 PM
Quote from: chessie4905 on September 11, 2019, 03:55:28 PM
Most items are in the parts book.  Finding them sometimes requires advanced sleuthing. Then, in the service manual, where is the fuel tank strap bolt torque specs?

I give - can't find it. Thought it'd be in either the 'body' or 'fuel' section, but I cannot find it.
Title: Re: GM Dash Light
Post by: chessie4905 on September 11, 2019, 06:44:12 PM
Not there. Also no info on removing and installing fuel tank, although it is pretty easy.
Title: Re: GM Dash Light
Post by: richard5933 on September 11, 2019, 06:57:05 PM
Quote from: chessie4905 on September 11, 2019, 06:44:12 PM
Not there. Also no info on removing and installing fuel tank, although it is pretty easy.

Trick question then. Surprising the info isn't in there somewhere, as it's pretty complete (at least compared to what I hear about the MCI manuals).
Title: Re: GM Dash Light
Post by: chessie4905 on September 12, 2019, 04:28:19 AM
There are two low air pressure warning switches tied into the push pull valve for parking brake. They are up in the area where all the lines go vertical where the floor level changes. Usually are accessible from inside of coach on face of riser last step. My conversion had this area covered over. Discovered them from underneath with a stethoscope. Of course they were both leaking some.They were next to impossible to get to. After several hours of reaching with all kinds of wrenches and screw drivers to loosen terminals, finally got them replaced.