Packard Forum Index » Post-War (1946-54)

1951 300 model.
Found the two screws easy enough on the top.
I can see the two nuts on studs underneath the dash on the bottom of the gauge cluster. I can barely get to them.
I cannot figure out what size they are !
I thought for sure they were 3/8's.
I have tried 5/16, 3/8, even 8,10.
In my sockets i saw an 11/32 but there is no way i am getting a socket in there.
Has to be a wrench.

What size are the nuts, on the studs, for the bottom of the instrument cluster ?
Anybody know for sure ?

Thanks.

The parts manual says the nut is #G120622 and the utility section say that part# is a cad plated 8-32 standard nut. McMaster has the standard 8-32 nuts at 11/32 wide. It might be worth investing in a set of ignition wrenches although you would need a midrange set because that particular size is not part of Amazon's cheapest 8 or 10 wrench sets. You may still need to loosen and drop the headlight switch though because IIRC, it is fairly close to the left stud and nut.

I can't remember what all I used, but I remember those two little nuts required LOTS of patience!!!

And I want ro pull my cluster again, but have been avoiding it.

Thank you ! And now i have an excuse to go buy more tools !!!

I've got lots of pics from my 53 if you need. I labeled everything as I took it apart.

I've got lots of pics from my 53 if you need. I labeled everything as I took it apart.

I think I just ended up using some small metric wrench. Can't remember the size. Just need to get them loose then undo then by hand. Do not put the nuts back on the studs when you reinstall. Leave them off for your own sake.

This video may have some helpful tips

On a 55-56 they are 3/8 drive.

I suggest cracking them loose with an open end wrench then spinning off by hand. They are almost never seized on. Just hard to access.

Edit: Actually, I can confirm that specific nut is 11/32 drive. Same as the rear window lower outside molding retaining nut.

So thats an adventure i will not be looking forward to again.
Would it have killed an engineer somewhere to make the wires another 3 inches longer !
Oh well.
All the dash lamps illuminate. Still no turn signal indicator, oh well. If i have my "ears in" i can hear the flasher element.
And the speedometer works smooth as butter ! Two days of soaking with some 3-1 oil and the demons have been exorcised ! No more bouncing from 50 to 90, and no more small predatory mammal noises above 30 mph. A little lube every 74 years does wonders for the speedo head !

11/32 nd is the size for those damn nuts, which i did not reinstall. Go ahead, judge me, i don't care.

Onto the next thing...

Is the flasher the original TungSol unit or is it the modern inexpensive 535 equivalent? If you hear the flasher clicking, do the outside lights work? The indicator light is between terminal 2 (flasher P) and the bulb socket should provide ground in a 49-52. Those cars with the single indicator light, not very much to troubleshoot other than the flasher itself, the connections or bulb. Later 53-56 models with two indicator bulbs is a bit more involved in grounding the indicator bulbs because the flashing bulb ground is made by being in series with the front bulb on the non flashing side but is still powered by terminal P of the flasher. Because the outside bulb filament is much heavier than the indicator bulb filament it does not get enough current coming thru the indicator bulb to light so only provides the ground.

If it is a 535, those flashers while advertised as universal or some ads even say positive ground are actually polarity sensitive and will work the outside lights just fine because that part is relay driven but the indicator light is transistor driven and will not work in a positive ground car unless the transistor inside the unit is changed. In place of a 535 you may need to find an original all mechanical TungSol flasher or go to a more expensive full electronic positive ground flasher.

Here is an extraction showing only the turn signal circuit wires and how bulbs are connected and selected thru the switch.