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Friend thinks he has one; to me it looks borderline impossible. What is going on when a valve sticks...and what does that tell you? What is the fix?

They do stick -- carbon, varnish, rust you name it can build up on the valve stems. The hot stem can bake it into something hard as a rock and act like glue between the stem and guide. Sitting seems to be the big contributor. I know I bent a few pushrods on a V8 that had sat and the valves rusted to the guides.

I don't think V8's were quite as prone as the long 8's but there are several tech bulletins -- particularly on the early 40's 356 engines where it was a continuing problem. Packard mentioned several causes and tried several "fixes". Ultimately it came down to more use, slightly larger clearances and better crankcase ventilation for those engines.

As to the fix, a couple of people recently have had to tear their engine apart using brute force to free them. If the situation hasn't gotten too bad possibly some snake oil for sticky valves in the gas or down the carb throat might help.

PatGreen,

Thought I'd share a few pics from some fun I had several years back. I inherited the pictured heads and as seen they still had the valves in them. I cannot state how long they were left outside, but I live in the desert and nothing ever rusts here so urban legend instructs.

I remember Craig asking me how easily the valves can out and I said that I didn't encounter too much resistance removing them. After he saw the pictures he couldn't stop laughing. I guess the hammer involved indicated otherwise.

Good question and I have one too for Howard HH et al, why is ventilation a factor?

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... et al, why is ventilation a factor?

Condensation is the one Packard was most concerned about. Mostly due to short engine runs and then storage. Under those conditions, lack of ventilation allowed moisture to collect on the valve stems and then rust. Low air flow also resulted in heated oil vapor not circulating inside the engine and depositing on various items. On the 356 engine they actually resorted to the little horizontal tube which catches air flow from fan and feeds it into the oil filler cap to force ventilation.

There are about a dozen articles on various sticking valve issues giving some reasons and methods to help correct them. Starts around 1939 service counselors and going thru 43-44. The 37-42 service index engine listing has the exact issue info.

Another major modern reason for valves sticking is old gas. Often a car will fire up and run more or less OK on even 2 year old gas--for the first time. The following day it will not start because of the nasty nasty gum that has built up on the intake stems. I often cringe when I read ebay stories about barn finds that fired right up.....

Of course, "it has a stuck valve" is often a euphemism for "it has a burnt valve".

Ross, Howard et al: Would a positive crankcase ventilation system be of any benefit to reducing stuck valves in infrequently driven Packards? I would think a PCV system would be relatively simple to make and install. Of course it would not be original, but could be made to be easily removed so the original draft tube could be refitted for judged shows.

(o{}o)

If the ambient air during storage is humid enough, it can also enter the engine via the crankcase breather pipe and tailpipe and given long enough storage, potentially rust valve stems. Though my winter storage is relatively short (4 months), I do tie a plastic baggie over the tail pipe(s) and crankcase breather and oil filler cap. Whether it's of any real benefit I don't know but it only takes a couple of minutes to do and undo.

I also want to add emphasis to what Ross says about "old gas" gumming up valve stems - it's a classic cause.

I'm not enough of an engine guy to know all the ramifications of PCV applications but don't see how it could hurt. Packard seemed to think more air moving around inside benefited idling and slow moving taxi cab engines. I don't think they were terribly worried about pollution back then so there must have been another reason it was done. If the taxi setup could be duplicated it might be an interesting thing to do.

Pierce-Arrow used a relatively primitive but I suspect effective crankcase ventilation system in their engines of the late 20s/early 30s era. These were updraft carbureted engines and they essentially routed what would have been the road draft tube to the air filter or flame arrestor, essentially drawing off the crankcase vapors and recombusting them. The advantage over the simple road draft tube is that the system functionrd whether or not the car was in motion, as long as the engine was running.