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As I zero in on getting the 52 fixed up ,The valves in the straight eight clatter .
The fellow that sold me the car said "that's what they sound like ,don't worry about it".It is a happy clatter something like the sound of a deisel ,
but my desoto with a 236 flat head six is so quiet when running you can barley hear it ,Ive had to put my hand on the car with the hood closed many times to see If it was vibrating or not ,to see if it was running or not.

I have a hunch the clatter is too loud and wondering if I should get the valves adjusted ,seems like a big job so I was wondering if I could do any "routine maintenance" ;the engine has an original 68,000 on it .I have had the piston rings replaced,by dropping the crank ,there were two broken oil rings on the car when I got it ,So the heads never been off ,I didnt notice any spots where the head is leaking gas .
.Currently the car does not smoke ,seems to have good vacumb ,starts up fairly easilly .The engine pulls well up the big hill I live on .I will borrow a stethoscope to check if its any one area on the head thats louder that another to check for generalized clatter vs one spot that is the loudest , and try to do so when the neighbors arn't looking so they dont think Im more nuts than I am .
So I am soliciting advice;

Could the timing be way off causing clatter? What is the proper timing ? right at TDC?
Does a regular timing light work on a 6v positive ground car? I am planning on getting one today .I guess I will need a dwell tackometer too .
If I change the timing, then I will have to redo the dwell, is that right ? I heard of an old mechanic's saying "timing affects dwell but not the other way around"or something like that ,very mysterious. The dwell was way off because I reinstalled points right out the box not knowing how to set them .I was insttructed by the machanic that they were off,and he adjusted them to 30 degrees dwell .this made a huge positive difference in quitness and higher end performance.As for the plug gap ,I did the same thing,installed out of the box ,whats the gap supposed to be? Could overgapped or undegapped plugs cause the valves to clatter because of poor combustion ?Inerestingly the clatter got much quiter after the Generator rebuild and the rewiring to correct the coil hook up ( it was wired backward)

Your car,if I am not mistaken, has solid lifters.Cars of that vintage usually require valve jobs the way cars of the late sixties required tune ups.It was just SOP.It does require a bit more work than your old chevy six as the valve covers are under the exhaust manifold and should be adjusted when the engine is hot.There are people on this forum such as Owen Dyneto etc who are experienced at this job and can give you a lot more information.

I'm really curious when you say you had the rings replaced, but the heads have never been off. Sounds improbable, and you have a head (singular). There are a few exotic engines (like the first series Twin Six and the Crosley Hot Shot) where the rings are replaced from below, and though it may be possible to do yours like that, it almost seems beyond reality that someone would try. The fellow who sold you the car and said they all clatter like that shouldn't be trusted for any further information.

If the clatter is reasonably constant, at idle, at speed, under load and not, then it's not ignition timing. If it only clatters when under hard acceleration, that's possible and likely. Sure, a 6-volt timing light could care less if you have positive or negative ground. No, changing the timing does not change the dwell. No, incorrect spark plug gap isn't likely to be the cause.

It's far more likely you need a valve adjustment as your car almost certainly has mechanical lifters. Check the engine number to be sure. A valve adjustment is a bit tedious but not otherwise a challenging task.

i think it's "dwell affects timing but not the other way around", and i think correct timing is 6 btdc. Likely a lifter issue as others have said, needing adjustment. The packard should run smoother than your desoto.

Steve, If your 1952 200 Packard was my car I would start off by removing the spark plugs and adjusting the gap as per spec in the service manual (which is available for downloading on this site, but probably about 0.028"). Next, I would make sure the innards of the distributor are in good working condition and that the points are in good shape and gaped correctly (about 0.016" I believe). The gap will also determine the dwell, but don't worry about the dwell. Next I would check the ignition timing for proper setting (the spec is in the SM). As pointed out above, changing the timing will not change the point setting gap/dwell, but changing the point setting gap/dwell will affect the timing. Then, I would do a valve adjustment. I agree with O_D about the rings being replaced without removing the head. It would be easier to give an elephant a root canal than do it the way you described. Good luck and let us know how things develop.

(o[]o)

Steve,
If you have a 12 volt timing light you can use it on a 6 volt system. Just connect the battery leads for the timing light to a 12 volt source, I use a jumper pack . A spare 12 volt battery would work also.
The shop manual will tell when valves should be adjusted,
Manual says every 2000 miles on my 38.
That engine should be every bit as quiet as the Desoto .
RT

thank you for the very helpfull info

the clatter is constant ,not just on a hill ,worse when cold
sounds like the valves need adjustment ,Ill have to enquire af the mechanic as it sounds tough !
I could do the plugs ,Id inspected the points and they are in great shape;
yes the fellow did pull the pan then the crank then the pistons out the bottom of the engine to fix the rings supposedly thatwas the way not to have to pull the engine perhaps I was gettiong my leg pulled

I don't think I'd go back to that mechanic again. To pull the crankshaft to do a ring replacement when all he had to do was remove the head and the oil pan - just nuts! The other advantage of having done it the "right" and easy way is it would have made it very convenient to check the condition of the valves, guides, etc. and if needed do a valve grind which these engines like every 40,000 or so miles, give or take.

Ive since moved across contry ,

the engine has about 70,000 mi So perhaps I should replace the valves when I bring it in ,who could grind valves correctly these days ! then have them adjusted ,

,I was hoping not to have a huge bill .

.Will a dwell tack read a 6 volt system correctly if it was designed for neg ground 12 volt engines?

At 70,000 miles chances are good you'd only be faced with replacing some (perhaps all) of the exhaust valves, intake valves have a much easier life. You also have to check the guides for excessive wear (replace if needed) and grind the seats. A machine shop can reface the valves and if the seats are still in good shape, they can be hand-lapped which, while not as satisfactory as a machine-faced seat, can still give very good service.

If you're mechanically inclined, doing a valve job is pretty straight forward if you can get some advice from someone who's been there and done it. Not too much in the way of special tools needed, and those can probably be borrowed. If not, look for an old-time mechanic or someone in your local PAC or PI regional club who does this type of work. If you were here in NJ I'd be glad to help you do it, I've done more valve jobs on these engines that I care to think about, perhaps you can find someone with similar experience near you.

This may be helpful to you.packardclub.org/forum/viewtopic.php?f=14 ... id=f5f11908485f65c549ded78d9feabbf8

Don't get preoccupied with a using a dwell meter, just set the points accurately with a feeler gauge and you'll have the correct dwell. Dwell is just an indirect method of measuring the point gap. I'm pretty sure a 12-volt dwell tach will not perform correctly on a 6-volt car. Polarity isn't an issue.