Packard Forum Index » Pre-War (1899-1942)

I think this might pertain to the original question, but I have gotten lost.

Here is an easy method for a check on your vac advance. Hook up your timing light and start the engine. As you give gas to oh, 2000 rpm or so you will see the timing marks march past the pointer. Now snap the throttle shut. If the vac advance is working, you will immediately lose more than half the advance as the carb shuts off the supply of vacuum. As the revs drop the other half will fall away as the centrifugal advance retracts to its beginning position.

Oh, and to clear a point, the vac advance retards the timing as the engine is placed under load. At 50 mph on a flat road you will have full vac and centrifugal advance. Encounter a steep hill while maintaining 50 and the engine vac will drop as you open the throttle; the vac advance will relax its position and let the timing retard a bit to prevent pinging.

I always hooked up a hand vacuum pump to the distributor tube. The unit should hold vacuum. Additionally, the unit feed is ported vacuum so the timing should react per the service manual specifications for a given amount - somewhere in the area of 11-15 inhg, but don't hold me to it. In other words, the unit doesn't need to be stressed to 25 inhg to be tested. You also can watch the breaker plate reaction visually using this method.

As well, timing is worth little if the dwell varies when you raise the rpm to 2,000 rpm. Varying dwell indicates a worn distributor shaft, breaker unit, and possible drive gear wear. This means the timing is not steady and can cause intermittent pre-ignition. This can cause engine overheating.

As for visual inspection of engine noises, you can buy instrumentation to measure such using a volt meter or DSO. The sensors can be glued or bolted to the motor with the wires run into the passenger compartment. Another method is to bolt a long copper tube to the motor and measure the resonance through the tube using a microphone. This will prevent distracted driving and the risk of crashing the car. This is also an easy way to isolate various engine noises by cylinder, chassis noises and rattles. On the proving grounds it is the only safe way to do such at speeds over 140 mph.

That's it for now. I have a paper copy of Dr. Zhivago and a higher mathematics book to work through to keep me from getting sick.

Thanks for the replies and info guys. If you knew how much I've learned in the last 4 years since I bought this car, and how little I still know, you'd realize what a neophyte mechanic I am!!! My knowledge and skill-set allows me to perform the basic 'monkey-see; monkey-do' stuff, but when it comes to dwell and vacuum curves, etc., I admit to being a little challenged. Not stupid, just ignorant! I will TRY and apply what has been suggested here and report my findings/results. Luckily, there is P.I. to assist and bounce ideas off, and for that I am most grateful.
I found a site that lists all the tune-up components for the '39 Six (https://hagensautoparts.com/packard/41-electrical/13607) and they show a replacement vacuum pot for $60 and I think I'll get a hold of them and confirm they are 'fresh' units, not NOS and just buy one. If I also buy a vacuum gauge and confirm the inhg's, I SHOULD be getting close. The distributor is NOS so is not worn and the engine a fresh rebuild, so I should be able to get pretty close to 100%. New points, condensor, plugs, wires and coil should all contribute to healthy performance, along with the foregoing suggestions.
Don: the above link shows the 2 Auto-Lite units I listed previously and confirm (I think) that they are the correct models for the '39-245 CID. The one I bought from you (IGS-4201) is identical to the unit that was in my car when I bought it (with the plate missing) so if it was original, I am fairly confident I have the 'right stuff'. Again, appreciate the time and input taken to respond. Stay safe, everybody! Chris.

Interesting info about the vacuum advance. I went to the website via your link and the vacuum advance for the 1951 Packard 200 Autolite distributor says $60.00. I just bought a vacuum advance for my Autolite from Max Merritt, $125.00 plus $75.00 core charge, plus shipping. Will explore it further and report back.

RE: the above post.

Sales (hagensautoparts.com)
10:03 AM (13 minutes ago)
to me

"Hello Steve,
At this time I am out of the Delco and Autolite advance. We can get yours rebuilt for the $ 60.00 or if I had it in
hand I might be able to come up with an exchange."

thank you

Brandon



I just quired the above supplier Hagens autoparts with a question on Vacuum advances and attached is his immediate reply. I hope this information can save you $ and get newly rebuilt fresh products too.

I helped a Packard owner in another country who was already buying a couple parts from me to save him shipping by getting the tuneup parts for him too and sending them at the same time. Some came from Napa but the points on his 1951 couldn't be matched and Hagen's came to the rescue! They had fast and very friendly service. I never heard of them before that but I was glad I found them.

Interesting info guys.... isn't it funny how prices can be all over the board on a given item? Not to 'talk out of school' but I just purchased cowl lacing from M.M., and the bill, all in, for the profile and the attaching 'nails' was very close to $100. Oddly enough, the shipment showed as coming from Amazon!! I looked up 'cowl lacing' on their site and there are 2 or 3 choices, of which one looked identical to what I received. Their cost was WAY lower and, although I didn't pursue the attaching fasteners on Amazon, my take was that M.M. was just brokering the sale through them and stepping heavily on the price. They must have some kind of a contractual arrangement with them as the product came in Max Merritt bags, but my takeaway was that, had I known what I was looking for, I could have bought direct at somewhere around half price. Now, before anybody slams me for supplier disloyalty, etc., I am the first guy in line to realize and appreciate the outlets that are in business out there to keep the supply lines open for us on these old cars, but 'just sayin', sometimes one has to watch and perform due diligence when winnowing through the choices. Some deals are definitely better than others!! Chris

Anyone can sell through Amazon.com and I have a number of things there right now, although only one relating to Packard. Likely Max Merritt uses their services too and has to mark it up to cover the Amazon.com fees, especially if Amazon.com themselves are handling fulfillment.

"Now, before anybody slams me for supplier disloyalty, etc."

Not at all, I understand that shopping for the best price is my responsibility, but.... who would expect a price comparison of a vacuum advance for $125.00 from MM and $60.00 at Hagens to be 100% more expensive at MM? I do operate using buyer loyalty but I feel like just I got a stick in the eye.......Sooooo, I guess it's back to Caveat emptor, check, check and verify.


PS: I also got an answer 2 weeks ago from Kanter pricing the same VAC ADV and was told $185.00 was the full cost.

Steve, I hear you loud and clear! And the lacing I was referring to, was about $25 direct from Amazon and how much could the attaching fasteners be?!?!? And Don, other than the Max Marritt labels being applied to the 2 bags, how much more cost is incurred by Amazon fulfilling the order FOR M.M. vs. them packaging it and sending direct?? Same product, process and packaging, right?? I get it that these companies are in it to make a buck, but when does it go from capitalist retail to scalping?? The TV news showed a guy the other day that had gone out and purchased a bunch of hand sanitizer and toilet paper and was going door to door selling it for double the price. The station absolutely vilified the guy as being a monster and a carpetbagger. My reaction was: Walmart does that on some items every day of the week and they don't even put them in their car and bring them to your door!! What's the big deal here?? Nobody HAD to buy the stuff from him, and why is it only scalping when HE does it?!?!? There are so many companies out there that are making OBSCENE profit on retail items...