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Bogging down at higher RPMs can be a sign of a plugged exhaust system. Usual causes could be a heat riser valve not opening or a partial collapse on the inside of a muffler.

So gentlemen a request for further help with this sick 1934 club sedan. I have taken all of your suggestions and gone through them from swapping plugs, checking the rotor cap, swapping plug wires and checking the vacuum. I brought in another gentleman to help me with diagnosing the miss in the engine. One of the first things he did was pull the plug wire from the far rear cylinder while the car was running and there was a definite miss. Interestingly, there was a loud "snapping" noise, like one that you would expect from a plug wire being held close to a grounding source. He continued to pull the plug wires sequentially and the third cylinder from the rear had no snapping sound and made no difference in the run of the car. This was the same on the number three cylinder from the front. Since we were concerned that the plugs might be misswired, we reviewed the plug schematic and each plug wire corresponded to the numbers on the distributor cap. We then followed the instructions on setting the dual points finding one set of points with a much larger gap than the 18-20 recommended. Reset it and then fired the car back up and there was no appreciable difference. In fact might have run a bit worse after resetting the points. We carefully looked at both the #3 and #6 positions inside the cap and they looked fine. Checked the compression on the number three and 6 both were good. SO we moved to the coils, swapping the two around as we followed the recommended procedure to ground them and see what kind of spark we got. The front coil was very strong while the rear was very week. After swapping the coils figuring that this might account for the number 3 and number 6 cylinders not functioning, they STILL were not firing. What was interesting is that when we began to sequentially pull the plug wires again after the coil swap from each spark plug as we did previously, there was a slight difference in the run of the car on the 3 and 6 cylinders but NONE of the wires created the "snapping" sound again.

So here is the question:

What is that "snapping" sound we were hearing that once we swapped coils disappeared all together. Was a coil grounding out somewhere else originally?. It was a very strong electrical sound that could be heard over the idle of the engine. Why did it go away when the coils were swapped.

Second, I had the points swapped out by another mechanic several months ago. They are a mod from Max Merritt. When I review old Packard materials about setting the point, I see that they utilized a protractor of sorts attached to the side of the distributor. Can a person get one? Is it needed? Is there another process for setting the points accurately without it? If the car runs down the road and missess, could the points be so off as to cause several cylinders to be dead?

Since I purchased this car it has always smelled as if running very rich. I am now assuming it is because i have more than two cylinders that are not firing or misfiring and sending unburnt fuel out the tail pipe. I often see wet black soot coming out the pipe onto the ground. No water in the oil that i can see.

Finally, can anyone direct me to a page where I can read how to walk through how to time this engine. I purchased the car after a major rebuild by the previous owner. This missing has been an ongong problem. I have a concern that there is a possibility that the distributor was reinstalled into the car incorrectly. I say this as for it to run half way well the distributor is turned such that the clip on the left side of the distributor cap is rubbing against the side of the rear coil. I have looked at alot of pictures of this engine to see if that is accurate and cannot tell. Seems odd that a clip would rub against the rear coil if the distributor was installed correctly.

It's really a simple ignition system, just a bit different in that it's 2 4-cylinder systems residing in a single distributor. There are several published guides to synchronizing and timing the 2 sets and there are also several ways to do it, you might see if the one I published helps you, it's on The Packard Club forum athttp://www.packardclub.org/forum/viewtopic.php?f=14&t=864

You'll also find several variations on the protractor type synchronizing too, I've added two pictures below. These can work well with care but if you have access to a Sun distributor machine, it's the easiest method. Though it's a hard way to do it, you can also do it with a timing light, marks for both #1 and #6 are on the front damper and you first time #1 in the conventional way, and then #6 by removing the cap and adjusting the other set of points on the small secondary breaker plate.

If you still need help, phone me or email me. I assume you're a member of The Packard Club, I'm in the roster, Dave Czirr in New Jersey. Or PM me with your phone# and I'll call.

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Well, surely take Dave up on his offer. Some things to check- The dead miss and lack of spark should be first diag as your problem though the weak coil and stronger should be an easy ohm check of the primary and secondary windings in each. I have had dist caps show the same issue so you should swap a new cap and condensors ( or known good ones temp)to eliminate these . Then swap the high tension leads for # 3 and 6 to see if the miss (lack of spark ) moves. If the issue still persists on the same two cyls it almost sounds like worn lobes on the shaft or bent or worn dist shaft with excessive play. This seems to make sense since you said the gap seemed large before readj. I suspect someone was trying to compensate for some worn lobes so to get any opening and spark on those the point gap would be setextemely large over all. It would make sense the that the problem worsened when you set to fact spec. While turning the engine by hand- slowly check the point opening for each lobe(cyl) with close insp for the cyls in question- checking for play/ wobble in the shaft at these positions. Zero spark on 2 cyls should be very easy to diag. The points either open, or they dont.

Easy enough to verify the coils, just buy or borrow two universal 6-volt units and tape into place and switch the wires over. Also be aware that if the hot lead inside the armoured shield hasn't been replaced there is an excellent chance the insulation is failing giving a an intermittent short; wire your test coils directly to eliminate this during diagnosis.

Even with a run of repro caps and rotors perhaps 15 years ago they will be VERY difficult to source. Check the cap very closely for crossfiring. And as already noted check the shaft bushings! - never fails to amaze how many folks think a grease cup is for show and ignore it.

Sorry 626. The lack of availability of such a common part as a disrtibutor cap is not something most have to deal with. The snap sound is the sound of the spark arc finding ground elsewhere when the plug wire is removed. This is certainly a common and normal sound for 12 v cars and resistor wires making 15000 or 20000 volt secondary voltage. As far as some wires seemingly producing a louder spark- could be a weaker/ stronger coil as you suggest but could be due to longer dwell and saturation from varying point dwell caused by worn lobes or shaft bushings. We could get into a long discussion about saturation/ dwell/ 4 lobe vs 8/ primary voltage / and rpm . Im sure it has already been hashed out here in previous threads. Surely this was the theory behind 4 lobe twin point / coil systems with a 6 v system. Later 8 lobe dual point v8 used overlap of the second point set to increase saturation and control contact bounce. Let me ask-#3 and #6 fired by the same lobe but on opposite point set?

The engine has the normal firing order adopted after the 2nd series Eight, 1-6-2-5-8-3-7-4. If I remember correctly, one rotor tip fires in sequence #1, #2, #8, and #7 in that order. In between each of those on the cap the other end of the rotor is firing #6, #5, #3, and #4. The plug wires are numbered on the topside of the cap under the cover so easy to verify if I remember it correctly.

Thanks for the info on the "snapping sound". I just don't understand why when I switched the coils around I never heard the sound. Your ideas make sense though. Again, I am assuming that one of the coils is bad. Which brings me to this question.

How do you bench test a 6 volt coil. I have them off and out. Which by the way, I want to offer up this bit of info. When attempting to remove one of them, I found that whoever had riveted the Northeast face place to the base of the coils holder had riveted the face plate through it and into the coil. This is the one I believe failed. Is this proper and/or could this cause it to fail?

Secondly, I read where if you test a coil on the bench from side terminal to side terminal I should see a resistance level of .75 to .81 ohms. I am getting 1.0 on both coil tests. It also says that I should get a reading of 10,000 to 11,000 ohms when testing between either side terminal and the center high tension terminal. I get nothing.

So, I have ordered a standard 6 volt coil to try in each position tomorrow morning. I understand I am looking at 350-550 dollars for two new coils? If anyone has any idea of how to have them rebuilt or where to go to get them replaced it would be much appreciated.

As for the cap. Yes, you are right. I am praying that it isn't the cap as I was told if I can find one im looking at probably another 600 dollars. I removed the cap today and checked the continuity through each spark plug wire to each terminal in the cap and all were good. I do notice on the #3 terminal, (one of the problem cylinders) that the plastic below the terminal inside the cap seems to be scraped away a bit? Does this mean I possibly have a wobbly distributor shaft? Neither I or the mechanic working on it with me seem to think there is excessive play. But why would I be seeing this scraping on a couple of terminals? Can anyone give me some guidance as to what constitutes a bad distributor cap? Further, anyone have an idea where to look for a new one if I should have to replace it?

I am going to pull the distributor in the morning and set the points per Dave's instructions. When I have it out, is there any good indicators as to how to check for excessive wear on the shaft. Anything else I should be checking for when I get it out. Most importantly, any guidance as to what to do or not to do when removing it?

(1) Forget about coil testing, results are not that reliable; the best test is the result obtained when substituting a known good coil. (2) If a rivet penetrated the coil canister chances are 99+% that the coil is no longer serviceable. (3) Only source for correct OEM style new dual coils is Bob Connolle, yes - about $400; I finally had to replace my coils this year - his product is excellent. (4) Just as a matter of good practice you should check the position of the rotor before you remove the distributor but in this NE unit it can only remount in one position as the drive slot is slightly off-center. Most find it easier to remove it from the head with the standoff attached. (5) To check for shaft or bushing wear a dial indicator would be nice but not necessary, preferably no side-to-side movement, less than 0.001" but even if you can feel a little movement if it's too little for you to actually see, it's serviceable. While it's apart remove the breaker plate and check the centrifugal advance weights and springs, at the least to see that they are intact and function - bogging down at higher rpms is often due to incorrect centrifugal advance but you'd need a Sun Distributer test machine to fully confirm though you can do a rough test with a timing light and tachometer. Cam wear is usually pretty easy to see visually but if in doubt, just mount a dial indicator and look for equal "lift" at each lobe. To check further you really need a Sun distributor machine. (6) Caps - on rare occasion you will see one on eBay, as of last year Max Merrit had 1 or 2 new ones for sale at staggering prices. I've had my '34 Eight for 50+ years and over the years when I saw one at a flea market I bought it on speculation, often for a few dollars so I have 3 or 4 used ones. Finally I found a brand new one so I probably have a serviceable spare I might consider selling if you find yours is NG.

Check the carbon brushes that make the connections from the rotor to the cap; there are two of them, spring-loaded with a small beryllium copper spring. The one most likely to cause problems is the one mounted off-center on the rotor which contacts the imbedded brass ring in the cap. The condition of the brass ring is also important - if it's scored or has rough spots it can sometimes be lightly resurfaced with some fine abrasive. Check both sides of the cap VERY carefully between the individual plug wire towers for signs of arcing (carbon trails) or cracks.

Once you solve the current problem and get to timing the ignition, it's possible you'll be unable to set the timing with the point conversion kit as the distributor cap hold-down clip may contact the rearmost coil and not permit the distributor to rotate far enough to reach the timing mark. I still use the OEM type Northeast points so I don't have this problem but have encountered it with others who used the conversion. Should this happen to you the solution is to elongate the 4 holes in the breaker plate so you can offset the plate slightly from the distributor body itself.

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Gents...just a note to say thank you for all of your suggestions. After removing the distributor, disassembling and inspecting it, setting the points, checking and cleaning the cap and wires and finally finding a rivet from the face plate of the coil holder penetrating one of the coils I am happy to report that the car now runs like it should. While still not as smooth as I like, no more high speed miss!

I'm now moving on to other issues that Dave was kind enough to make suggestions on over the phone to me. I'm confident that those too will be sorted out in due time.

Many thanks to all of you!