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

Hi Owen,
Never mind, found the guidance in the tune-up document - Thanks.
Mark

Dear Mark:

Given the electric pump, what is needed here is a step by step approach to isolate what system is causing the problem.

1) Get the car into a no start situation.

2) Pump the accelerator a few times and check for fuel. Using a squirt oil can squirt some gas down the carburetor. That will isolate a fuel delivery problem.

3) Using a KD Tools spark tester set to 20Kv (available from NAPA) and connected to ground; check the ignition. You should have a good strong spark.

4) With the motor hot pull a plug and using a screw in compression tester crank the motor with the throttle wide open. If the compression is well below 100 that may be a problem. If the cranking speed is slow that is also a problem.

Hope this helps.

OK Guys,
I am definitely not Mr. Carburetor, but I am trying to check the Anti-Perc Valve adjustment. I've got the dust cover off and magically, I can see them. The valves are clean, the lips on the AP arm are up out of the way and I can barely see the indicator line on the stems.
However, the tune-up guide is baffling me. I see that this is one of the last adjustments with a warning not to screw anything else up.(Makes Ssnse).

I don't understand the very first step. "Back out the throttle adjustment screw." (where is that?)

The rest of this makes sense, you put the feeler gauge between the stem and the arm and adjust so the indicator line is flush with the top of the plug, as follows.

"With throttle valve tightly closed, insert .015" feeler gage between AP stem and lip on AP arm. Bend lips on AP arm so indicator line (presumably on the stem) is flush with top of anti-percolator plug."

Can someone describe the throttle valve so that I can close it?

Feel free to tell me I am over my head! Thanks.
Mark

Wow!

As ususual I made things more complicated than thet were. Throttle valves just too obvious - they are connected to the throttle! Duh.

Anyway the real shocker is that my measurement of the existing gap to get the indicator lines to the top of the AP plug measures about .090 - about six times greater than it should be (.015)!!!

So, before I start adjusting the lips on the AP arm, my question to the experts is this..with the gap this much off, would this essentially make the AP valves totally useless and non-operational? If so, I think I may have found a major part of the problem.

Thanks guys,
Mark

Are you sure the "sticking acclerator pump" you mentioned in your first post was correctly fixed? As I recall they all operate off the same shafting and thus one adjustment affects the other. Reread the service instructions again making note of the sequence of adjustments and I think it should all become clear.

Thanks Owen and Happy Indepence Day to all!
I hope I am not wearing out this thread, but here goes.

I think, short of removing the carb and tearing it down, verifying the accelerator pump fix will be a problem. Given that she runs well at speed and starts well cold, I think I am safe in assuming all is well there.

The literature lists the AP valve(s)adjustment as the last procedure, and warns not to disrupt any other adjustments when adjusting the AP valves.

Granted I do not fully understand how the AP valves function other than they fix the foaming problem, (as I recall by draining fuel back to the bowl).

If my initial finding is correct, it will be an unexpected and major adjustment, as I previously mentioned. I suppose it is possible that the rebuilder simply stopped short of a full adjustment - it was a rather rushed affair to get the car ready for shipment.

I will do some more study, check the price of a new carb (in case I really screw this one up) and let folks know what develops.

Thanks to all,
Mark

Hello Packard Friends,
I can wrap up this thread with a report that the Clipper is running most excellently, thanks to the help and guidance I received from all of you.
In a nutshell, given that the anti-perc valves were so way out whack, it made the previous carb "rebuild" suspect. So, I installed a remanufactured unit from Max Merritt. Wow, what a difference - very satisfied.
Also, the timing was way, way off. Perhaps set so, to compensate for the messed up carb.
And, the gap on several spark plugs was way off.
Therefore, I am happy to report very quick starts, even when hot, and smooth running at speed - what a joy! I haven't tried the "nickel on edge" test yet, but I am tempted.
Thanks everybody, I am a happy fellow today!
Mark

Glad to hear the report that your hardstarting problems are over; always nice to read a successful diagnosis and cure story. Yours just demonstrates the many meanings to the word "rebuilt".

Proper adjustment of the anti-perc valves (on those carbs that use them) is important and I'm frequently surprised at how often they are mis-adjusted or just plain ignored, and how their function is often not understood.