scott12180

Interesting. . . . " X stands for special or wide gap." So on an AC 48X, the electrode gap is wider than on a 48? If that's so, couldn't you just make the gap whatever width you wanted it to be? Why the special designation? Also, anyone hear of a Prestolite spark plug? What's in the Packard now are Prestolite 147's. I'd like to find out what heat range they are because they appear to be too cold. The only cross reference I can find is on sparkplug-crossreference.com which suggests they are about like an AC 45. If that's true, then I do want a hotter plug, like AC 47 or 48.

Does anyone know in the AC sparkplug nomenclature, what an "X" suffix means? What's the difference between an AC 48 and 48X? or AC 46 and 46X? I haven't found any explanation, yet. --Scott

With your suggestions, I've discovered these cross reference charts. None of them cross the old AC nomenclature (K9, K12) to the new (46, 47, 48) but they might be useful for other brands. http://graylady.atwebpages.com/sparkplugs.htm http://www.oldengine.org/members/diesel/Plugs/equiv.htm

Packard service literature in the early 1930's recommends AC spark plugs--- type K9, K10 or K12 for my 1932, depending on the heat range. I've yet to find a list of what the modern designation for these plugs would be. These are 14 mm plugs but what's important is the heat range --- K9 is cooler, K12 is hotter --- and especially the reach into the cylinder. I'd like some NOS plugs. Nothing much on eBay. . . . Any suggestions? --Scott

Has anyone here bought a new Detroit Lubricator from packardcarbs.com, the fellow who makes these updraft carburetors in Post Falls, Idaho? I'm wondering if you were pleased, did the carburetor perform well right out of the box or did you need to do a lot of adjustment. . . . Does it make your car run great? I'm more interested in a well running engine than a showpiece, but it would be nice to have the correct carburetor for my 902. Thanks for your comments. Feel free to send me a private message if you'd rather. --Scott dwyer12180@gmail.com

Spark Knock problem appears to be solved. I replaced the advance springs on the distributor with some stiffer springs which I had --- one of the original springs looked so weak that it wasn't even in tension when fully advanced. That alone made the car run so much better and no pinging. The advance is now set at 9 degrees on the flywheel, exactly what is recommended. Thanks to Paul "PFitz" for the suggestion and hence reminding me that I had this similar problem 30 years ago on a Franklin. Now to do something about the carburetor. The engine is running so nicely right now that it's hard to believe that the Zenith marine carburetor is doing harm. Sort of like how you might feel great when you drink scotch and smoke cigars. Thanks to everyone who offered a suggestion. This was a good learning experience.

The carburetor on the car is Zenith 10870B. The spare shown in the photo is 11583D. I can't find a chart explaining exactly what these are, but a Google search suggests that they both are Marine. Some road testing today where, suspecting the carb is running rich, I closed the main jet screw half turn at a time to assess running. It seemed to get better and better but then I noticed that the main jet was fully closed ! The car still ran great, which puzzles me (how can it run with the main jet closed???) , but on a short steep hill, it lost a lot of power presumably being too lean. So is Paul "PFitz" correct that I should run it rich on the flat so it is compromised to be OK on the hills? It was one and one half turns open. BTW, if you do have a marine carb, there likely is no power enrichment circuit like a car needs. The lack of such a circuit will make it lean out on hills. This was a problem with the marine/stationary engine carbs that were showing up as replacements for the potmetal carbs of the late 1920's. They run ok at idle and on level roads, but with no way to properly enrich the mixture proportional to engine load, such as hill climbing, they go too lean. So, typically, the owner's opened up the main jet to "compromise" for hills and then the carb is running too rich when not under load. Sound familiar ? --PFitz I still don't understand how the carburetor can run well with the main jet fully closed. Iagree with Ed that I'd prefer to run a proper Detroit Lubricator but the reproduction ones are $3500, if they are even available. That's a bitter pill to swallow right now. Any suggestions for alternative sources? Or other automotive carburetors I could try out?

I swapped some advance springs on the distributor today. What was there seemed very weak ---- one spring wasn't even in tension. Easy enough check because I can always put the "original" springs back. Now I've got slightly stiffer advance springs. I'll road test without changing anything but I am doubtful this alone will solve the problem. Unfortunately I don't know of anyone with a similar car to borrow a correct working distributor. That would be ideal. I will check as best I can to be sure number one is at top dead center since the flywheel is right now at 4 degrees advance. Should be pretty darned close but without removing the head or the oil pan, all I can do is insert a bent wire and determine if the piston is nearly flush with the deck. I got something like 9 mpg before I started any of this. I thought with a 320 cu-in being driven reasonably gently I should be getting 12 mpg or more. The pinging was annoying but a back burner concern. Then I began to measure clearances and specs. . . . Pandora's Box opened. I still think the carburetor is running rich. Someone posted a service booklet for this Zenith, which apparently is a Marine Carburetor. I'll study that. Would excess carbon buildup cause spark knock pinging? --Scott

Wow, thanks very much. I think that's it --- a Zenith Marine carburetor. I'll read it through tomorrow. --Scott

George is right not to start mucking with the carburetor just yet. What started this, however, was poor fuel economy that made me think about what was what. That's when I began to check everything and discovered the source of the slight pinging was timing. However, SaddleRider suggested that due to the unlikelihood of spark knock in a car like this without huge advance, a mechanical failure could cause pinging, which was exactly what I originally feared. But what could fail to cause that kind of sound? Paul's comments on distributor advance reminds me of a 1925 Franklin I once owned which, as I try to recall from 30 years ago, ran very rough at road speeds. I don't recall pinging, just rough running --- lurching, hunting. Someone at the Franklin Trek (the late and very much missed Don Kitchin) tightened the advance springs on the distributor and the problem was permanently solved. I wonder. . . . I will certainly take a look. My only fear is that I do hear pinging at highest rpms, like 50 mph, going up a slight incline. I would think that with 4.69 gearing at 50 mph it should be fully advanced no matter what. Again, thanks to all you who are contributing your thoughts. I very much appreciate being able to bounce ideas around with you guys. Let's keep the thread going and I'll keep you all posted.

My 1932 Packard 902 has a large Zenith carbuetor which a previous owner installed. (The photo shows an identical spare.) I do not have a Detroit Lubriucator. Could someone tell me or point me to a website which goes into how I should properly adjust this carburetor? Also I'd like to know which model carb this is. Nothing written on it save for a circular brass tag with some numbers. Am I correct that this carburetor has an adjustable main jet? Is that the brass screw-in thing on the lower right side? Thanks --- Scott 32 Packard 902 Victoria Coupe

I did not have the spark advance set at 28 degrees, but the dwell angle was 28 degrees when I first measured it. Anyway, with the new dwell set at 33 degrees and the points gap at a corresponding 0.012", the road test was quite a failure. The engine sounded like the anvil chorus with the knocking/pinging so bad that after three or four miles I had to pull over and retard the spark by rotating the distributor. I finally found a maximum advance with no pinging and continued on. At my destination before I began the 35 mile trip home, I thought that the engine had not seemed "well" after retarding the spark. Out of curiosity, I reset the points gap to 0.019" (with a corresponding dwell much less), and the car seemed to run much better. Slight pinging. Once home, that 0.019" points gap measured to be 4 degrees advance on the flywheel. So I noticed really nothing at all regarding dwell. The engine felt better with a large points gap (smaller dwell) and 4 degrees advance than a small points gap (33 degree dwell) with the same 4 degrees advance. Now I'm wondering about carburation. The car has a large Zenith carburetor which I don't know much about but will ask my questions under a new thread.

Apologies for not replying sooner. Life gets in the way sometimes. . . . I checked the dwell on the 902 and found that I had about 28 degrees with a points gap of 0.018". I adjusted the dwell so that I now have 33 degrees, (Grimy recommended 34 degrees) and the points gap falls in at 0.012" --- quite a difference in gap. I also set the advance to 4 degrees on the flywheel, which corresponds to the "high compression head" setting in the specs. Tomorrow I'll go for a long ride and see what happens. I can always adjust spark timing on the road. As for the distributor at TDC, I did not dive into that yet but as I recall from the rebuild on this and my 236 (long ago) you can't be off a tooth on the distributor drive, nor even 180 degrees --- there is only one way it can mount. Unless there's a "toothed drive gear" deep inside the engine, like driving the oil pump. So nothing I can easily change. (I could be wrong, of course). Also haven't yet determined that Number One is at TDC. That will take some gymnastics. I am not being a good scientist because I'll be changing two variables --- I cleaned out the gas tank recently and wanted to see how the car runs on non-ethanol. So I'll have the new dwell and non-ethanol. I'll report back how it goes. --Scott

Thanks for the advice on dwell. I'm going to appear very ignorant here because it's late and I don't want to spend the next hour searching Google. . . . Could someone explain the importance of the dwell angle? Or just give me a tutorial on dwell from basics? To me, it seems that dwell is determined by the points gap. Larger gap, smaller dwell. Dwell governs the amount of time for the ignition coil to "charge" before the points open and the spark is thrown. But as long as the points gap is reasonable, how else do you set dwell and why is it important? --- A bear of very little brain with a Classic Packard.

All your comments and advice is much appreciated ! Thanks very much. I'll give the vacuum method a try for comparison. . . . when I can find a vacuum gauge. And check the timing marks. Regarding twin points, this Northeast distributor used to have twin points but at some time someone converted the ignition to a single set of points with a new backing plate. I don't know the details but the previous owner might if it makes a difference. --Scott

What I am doing is, with the engine off and cold, removing the starter, setting the pointer in the starter "window" for the degree advance setting recommended, then rotating the not-advanced distributor until the breaker points open. Is this not the correct way to set spark timing? To my knowledge, there are no other timing degree marks except on the flywheel exposed by removing the starter. Or is this procedure supposed to be done with the engine running using a timing light ?!? Never occurred to me.

I'd like to clean the rust and dirt out of the gas tank on my 32 Packard. I was going to use sharp rocks or nuts and bolts and shake it with dish detergent as I've done before, then use a sealer. But for one thing: The baffles between the three chambers of the 25 gallon gas tank don't have holes but a screen between sections. So whatever I put into the filler will not get into the other two chambers. And I doubt that gas tank sealer will either ..... or it will seal the screen between the baffle. Any suggestions? I've a couple of ideas but appreciate your advice. How about EvapoRust? Or what? --Scott Troy, NY 1932 Packard 902 Victoria Coupe

Curious question: Car is a 1932 Packard 902 Standard Eight. Rebuilt engine -- new bearings, pistons, valves. I thought I had a noisy valve or two or three --- a tappet-like clicking sound --- so I spent time adjusting all close to spec. I was next working on the ignition and went for a test drive, and noticed the valve clearance noise was much worse. Not anxious to dive into a hot and running engine again, I wondered if the spark timing might have anything to do with it. And it did. I retarded the distributor on the roadside until the clicking noise went away. The engine was quiet and smooth. So the clicking noise must have been spark knock and not valve clearance. Right? So the question is, would modern 10% ethanol gasoline cause pre-ignition or spark knock when the timing is set to 1932 specs? Packard offered three heads in 1932 --- low compression, standard and high --- each with different spark advance settings. (I don't know which I've got) Low compression was 12 degrees, standard 9 and high 4 degrees. I thought modern gas could accommodate far more spark advance than in 1932, so I tried 15 degrees and heard the loud clicking knock. Roadside adjustment ended up about zero degrees for a quiet engine. I just set it to the 4 degree mark. But I am puzzled. I could try a few tanks of non-ethanol, but I'd rather hear your comments first. Thanks again. You guys are great. --Scott

I did mean Sta-Lube. My apologies. And my car is a Packard 902 with a three-speed synchromesh transmission. I've learned to place little value on the pontification of those with advanced degrees but little practical experience. I'm glad that you caught your differential before major damage occurred. Experience is the best and only teacher to trust. Since the Shell Valata and Exxon Cylesstic are straight mineral oils, I think I'll use the Cylesstic TK-1000 as long as it gives quiet running. I may change to the lower viscosity Valata when the weather turns cold, if I continue to drive. However if anyone on the forum has experience with these, I'd welcome your shared comments. Thanks to all for your thoughts.

Yes, it helps. Thanks. For what it's worth, I've used two kinds of what I think are straight mineral oils, although with fatty oils thrown in because they are primarily marketed as steam cylinder oils. One is Shell Valvada 680 and the other is Exxon Cylesstic TK 1000. Both come in various viscosities, but I happened to have these two in some quantity. They are close to the Model T 600W differential oil that you mention. I don't know if they are good for a transmission, though. Especially one with synchronizers. That's why I asked. I will share two observations. I recently drained the transmission on the '32 Packard because I didn't know what was in there, and found that it had this Exxon TK1000 that apparently I put there years ago. (I've owned the car twice, now.) I filled it with StaBil GL-4 85W-90 and on a 100 mile trip noticed that the shifting was much more difficult than it was. The other observation is that I had Exxon TK-1000 in a 1926 Packard, but when the weather turned cold, experienced considerable howl in neutral until things got warm. I changed to a modern gear oil with Lucas Stabilizer which quieted things down well. So the TK-1000 might be OK for summer use, but too thick for cold-season use. The 85W-90 is definitely too thin for summer driving. --Scott

>> .... which is not harmful to yellow metals. I'm sure I don't have the precise terminology correct. I choose to use straight mineral oil in transmissions and B/W overdrives, and GL-4 EP in pre-war hypoid differentials. Could you please share what, then, you use for a straight mineral oil?

I have a 1932 Packard standard eight. Is there yellow metal in the transmission or differential? Brass and bronze are not compatible with gear oils rated GL-5 due to the high sulpher content, so I understand. But I don't know what's inside a Packard transmission or rear end of this vintage. Can I use a modern GL-5 or should I look for a GL-4 or other low-tech gear oil? Thanks -- Scott Troy, NY

I have a 1932 Packard standard eight. Is there yellow metal in the transmission or differential? Brass and bronze are not compatible with gear oils rated GL-5 due to the high sulpher content, so I understand. But I don't know what's inside a Packard transmission or rear end of this vintage. Can I use a modern GL-5 or should I look for a GL-4 or other low-tech gear oil? Thanks -- Scott Troy, NY

On a Packard which had the Bijur chassis lubrication system that is still functional, what type of oil could be used today? Something tacky like chainsaw oil? Something with more body like gear oil? Engine oil seems too thin for the job. Thanks --- Scott Troy, NY

Since rebuild, probably not much more than 300 miles. That was 12 years ago because the car sat in dead storage for a long time until I got it . . . got it back. Long story, but I did the rebuild back then. New connecting rod bearings, original crankshaft journals, rebored, new pistons, valves. Original mains and camshaft. --Scott