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

Quote:

73 isn't exactly young but it looks like not young enough either as we were both wrong!

Quote:

You're still young! My mom was just telling me the other day that she wishes she was in her 70's again! She's 87.

Like Roland I have good news to report! Kick down is now working, and working well. I tried doing a reverse setting, that is, locking my throttle all the way open and then locking my throttle valve in the most forward position. This worked, but it was too sporty! I adjusted it again it so it is a little advanced from the factory setting.

Roland, I think if you "cheat" your throttle valve too much it could prevent your carb from fully opening as the throttle valve has a hard stop in the fully forward position, hence the spring on the throttle shaft.

Here's what all I did.

Measured and shorted the throttle valve control rod. (Apparently a little too much.)



As Ross noted the rubber bushings were bad in the bracket that bolts to the firewall. I disassembled it, put a little epoxy to fill the gaps, and riveted it back together.






Cleaned and worked the spring on the throttle linkage to make sure it could easily and fully expand.



With the cross-shaft secure I was able to reset it's position and then I lengthened the push rod from the pedal to the cross-shaft. Another one of Ross' suggestions. I'm starting to think Ross is a pretty smart guy!



Now, with what I would consider normal acceleration, the DD engages around 35 mph and feels good, that is, it's smooth and the car continues to accelerate just fine up to highway speeds. I can get the DD to engage around 20 mph if I accelerate to a little over 20 mph and then let off the accelerator.

Up to a little over 50 mph if I put the pedal down it disengages the DD no problem. I think I have it set so that it disengages at the beginning of "beyond full throttle". I think I like how it is currently set, so no plans to play with it any more.

Great you got it working, too! Must be a lot easier on the engine to pull away with higher revs when needed, e.g in busy traffic or uphill. Good you have your kick-down back, too. A bit tricky with all the couter-acting rods and levers. I also have this floppy action of the bracket which holds the horizontal trottle rod (the one which crosses the rear end of the engine). It allows the rod to move back and forth by some measure. And, of course, it flexes left and right. Not sure what this is good for. Trying to solve the stoic DDC problem, we locked it in its mid-position by another small bracket, but it had no impact on operation. May be it's a device that is to decouple the gas pedal from movements of the engine relative to the cars body. Packard was picky with smooth operation. I removed the 2nd bracket again and let it flex and flop as it it wants to.
I re-located the return spring, though, to the lower part of the throttle mechanism, closer to the pedal bracket. This gave me stronger spring action and avoids all interference with the vertical accelerator rod (shown on your last picture). Also, it stabilised the floppy bracket more in a mid position. Can send a photo when I have the car on the hoist next time.
Glad we could solve the riddle without tearing apart the transmission.
Cheers, Roland

Quote:

Yes, that should always be where it disengages, as the kickdown region of the throttle valve is directly past the regulated pressure region, which should correlate with full throttle plate opening in the carb.

However, if you have to mash the gas pedal into the carpet or against excessive spring pressure to even reach that point, then it will be annoying to get it to kick down.

So as we see, when adjustments are made to reverse 71 years of aging and fiddling, the suggestion that Ross and I made to basically just tap the gas to get it to kick down, should be easy to do when driving. That is to say, how people were driving these cars when they were new.

Good to hear the positive results from both of you.

Quote:

People fiddling with things, trying to get them to work, is certainly a problem on older vehicles. The lack of understanding of how the older technology worked, and was to be maintained, can be a problem.............it is for me! But, little by little I'm getting all my car's systems figured out!

This is the spring loaded "kickdown" turnbuckle/linkage off a V8 car. (6480849) You can see how it pulls out under tension. Full travel (not shown) is about ⅝". The same part is used on the overdrive cars.

Attach file:

---

  20241117_182142.jpg (1,763.25 KB)