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

Thought I would start a new thread about the 51 conv. top problem so it be easier to follow.

We added fluid to the hydraulic canister and it was about 1 inch below the line where it should be. But still the top wouldn't go down. Before this the top worked fine, maybe a little slow but it did work. Owner says hydraulics were completely rebuilt about 6 years agoand everything looks new and clean. Where should we go now to trouble shoot? When I pull knob to lower the hydraulics jumps like it has juice going to it but I'm not sure what it's supposed to look like when it's working. Let me know what's next.

I'm assuming the pump does run normally both in trying to go up or down so we can rule out electrics?

Does the car have hydraulic windows and do they operate normally going up? Is the knob moving the top valve lever all the way when pulled or pushed? If it has regular windows and top valve is moving all the way, would check pressure and relief valve per instructions.

If it has windows and they work OK or if pressure is good, then about the only thing left is the top valve itself or maybe during operation something was loose and moved and is now causing a bind in the top mechanism.

Doubtful it would suddenly show after all these years but one other thought. Any remote chance top hydraulic hoses were changed to something incompatible or something contaminated fluid and hoses swelled?

Attach file:

---

  (34.33 KB)

The windows are manual.

Is the knob moving the top valve lever all the way when pulled or pushed? If it has regular windows and top valve is moving all the way, would check pressure and relief valve per instructions.

The above statement I'm not sure about because I'm a novice for sure. Can you be more specific with details as to how to do these things--thanks

The top valve is a large round affair bolted to the firewall behind the knob and a rod connects the two. You can see the arrangement with contortions and looking under the dash while moving the knob. Just verify nothing appears to be interfering with the movement such as something loose or a wire or something else dropping down preventing full travel of the valve when knob is pulled or pushed.

If you wanted to check the relief valve, it is behind the hex cap as shown highlighted in the photo. Depending on mounts, the pump may have to be removed to access and remove it. It is one of those things that needs to be done carefully so as not to damage or lose anything. The cap is spring loaded so pieces may come flying out.

If that is OK, then I think your next step is pressure and for that you will need tools, gauge and hose connections. Just what depends on where a measurement attempt is made. You might have to take it to a shop.

Attach file:

---

  (8.43 KB)


  (26.17 KB)

Thank you, I'll keep you posted on what I find out or what happens. The statement about parts flying out is intimidating :)

We were gone all last week and we plan on getting into the top this week, will let you know what happens.

Okay, we charged the battery all night then started her up the next day and let it run about 10 minutes and the top performed fine. I guess chalk it up to beginners error. Thanks for the help you guys provided.