When I turn on my lights the instrument cluster lights up pretty good from the top down to everything below it BUT the gas gauge is a bit hard to read at night. Is there a bulb specific for that gauge? I reach behind the cluster and can feel 4 or 5 diff lights that spin out. I replaced bulbs in two of them on/near the gas gauge area but no diff. Even with them out the other warning gauges still came on when I turned the key and and then started it. I don't get it. Are these lights for something I don't have on my car as it is a bare bones car?????? Is the light I am getting jsut from one or two main lights at the top of the cluster????

 

Do you have the chassis service manual for this car? It would be supremely helpful if you did as there is a diagram in the chassis electrical section, giving a view of the cluster from behind, and showing exactly where each dash illumination lamp is and what it lights up.

I don't have the '74 manual, but attached is this diagram from the '73 manual. I think the '74 dash cluster is when Olds changed it from the square arrangement of '71 through '73 to the oblong arrangement of '74 through '76, so I don't this will be useful to you, but it gives you an idea of what the diagram looks like. But you definitely need this manual and the equivalent diagram if you're going to be trying figure what bulb illuminates what gauge and where they're located.

 

Note in that diagram above that the instrument cluster illumination lamps are labeled "A" and that there are only 3 of them, one each on the left and right about half-way up and one in the center near the bottom. One thing I've noticed on my '73 Custom Cruiser is that the instrument cluster is not exactly lit up like a Christmas tree at night, especially the fuel gauge, which is at the top of the cluster, at least by the standards of instrument clusters in today's cars, although it is perfectly adequate.

 

are there any PDF files avail to download for manuals?

 

The Auto History Preservation Society, which used to be Wild About Cars, has them only through 1973. I don't know of another source. For all the work you're doing to this car, you really should have your own paper copy, anyway. There is no single better investment you could make in the restoration of your car.

Here's one right now for all of $12 plus $5 shipping.

http://www.ebay.com/itm/OLDSMOBILE-1...d03435&vxp=mtr

 

DUMB ME. I bought a manual. Totally FORGOT. Sorry man.

 

So far I can't find a nice pic of the circuit board.

 

Just remove the cluster, disassemble it, clean the parts up (being careful of the possibility that some of the instrument markings may be water soluble), and check all of the sockets and printed circuit connections, and you'll know just how everything works, and be very happy with the result when you reassemble it.

- Eric

 

That requires MAJOR dash disassembly on 74-76 big cars.

Tim, there should be something in the electrical section of the CSM. I can't remember offhand which section that is in the 74 book but I'm pretty sure it's in there.

 

You can replace all of the bulbs without disassembling the whole dash. You can simply pull out the faceplate and speedo parts and access all of the bulbs from the front side.


I wrote up a step by step on how to do this for a friend. If it would help, I'm sure I can find it and send it to you. I believe I also have a scan of the page from the manual showing exactly which bulbs go where. They're not just all 194's if you want to do it correctly.

 

If this is in the '76 manual, it should also be in the '74 manual, which he has. What section/page is it in/on? That might help him find it.

 

That's what I was thinking. It's all pretty clear in the Chassis Service Manual, though I will admit I haven't done it myself, as I have a '73 (which I did do it on).

- Eric

 

I was able to change bulbs in the instrument cluster on my '73 Custom Cruiser by removing the lower trim panels below the steering column and on either side of it and then just reaching up under there with my arm. You can feel around and figure out which bulb is which while looking at the diagram in the manual. Granted, the right side trim panel is a big piece, stretching all the way across to the passenger door and requires moving about a dozen screws, but presumably you don't have to change bulbs more often than about once a decade.

 

I like to disassemble the cluster of any car that I actually pay attention to.
In my '73, the inside of the cluster was filthy, and the gauges were much better and more evenly lighted after I cleaned it.
The '73 cluster is a bit of a %#ch to get out, though.

- Eric

 

I attached the page from the manual...section 12 (chassis electrical).


Here are the steps I sent my friend for doing the same on his '76 98 Regency sedan (same dash as your '74 88)




- take out the 3 phillips head screws that go UP into the speedometer glass
- take out the 4 phillips head screws that hold the black trim in place
- At this point, you can slide/lift out the faceplate that has the shifter indicator printed on it, just be careful with the shifter needle. It's sometimes easier to turn the key forward and move the shifter through the gears to find the easiest position to lift the faceplate out.
- Now you can pull out the message center bezels and you'll see the bulbs behind them. You should also be able to see the illumination bulbs as well. It's a curious mix of nearly identical bulbs but the differences are in the lumens ratings and when all of the right bulbs are in place, it looks great at night and just has a more "factory-correct" look about it.

From memory, I don't think you need to remove the speedometer itself to get to all of the bulbs. I hope I'm right. If you do need to remove it, you may have to push on the cable release which is on the backside of the dash cluster and can be tricky to reach with the dash installed. I think you'll need to remove the fuel gauge but that's 2 simple 1/4" screws and pulls out/pushes back in easily (just be gentle with it). If your car has the "Fuel Economy" Gauge, you may need to pull it out to reach a bulb as well. Same as the fuel gauge, except 3 screws and there's a vacuum line attached to the back....just unbolt it and pull it forward enough to reach the bulb.