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Ok...found out why body was rocking at idle..even though the engine sounds smooth to me.i pulled plug wires off #1 then #2.engine rpm don't change.pulled plugs and they are firing good.the plugs don't look like they are burning any fuel.i guess it looks like I'm running on 6 cylinders...the back 6.how can it sound that smooth...I really don't hear any skipping...I hope I haven't damaged anything.ive driven it some and drove it at least 50 miles home when I got it..I'm perplexed but I think those two front cylinders are not getting fuel...plugs look new like they have not burned any fuel...they were installed right before I drove it home...any ideas?I've ran some marvel through carb..no help.would it help to drive it or will i make it worse...49 288...thanks yall

I'd recommend you do a compression test. If you don't have a gauge, for a really primitive test just remove the plugs and hold your finger over the hole and crank the engine.

You can pull the cover off the side and expose the valve train and see if they are working or not/where you adjust.
The intake would have to be partly plugged, if not getting fuel mix, if that's operating Ok. Mice make strange stoppers. A bore scope or fish a wire may lead to clues. I use a blow gun with a plastic tubing in place of the nozzle and fish it in places and see what comes out. Compression test is another easy option. (Don't ask me how I had acorn shells in #8 and the plug was in.) I always check for that stuff before I fire up. Prevents damage. Too much emphasis on getting them running "right away", but not right way to go...
I don't recommend you mystery oil down through your carb. Add to gas or the crank case, but what are you doing it for if it's a mystery and you don't know what's wrong? Do you really need it or just because every else does it?
If they're firing but not burning, the exhaust manifold won't get as hot there, so an exhaust thermal scan would provide clues. Those are pretty cheap at the chinese takeout now. All this could have been prevented with a systems approach.
I bet it's something else.

Do a compression test. If both 1 and 2 are very low there is a good chance the head gasket is blown between the two. Do look at the valves and make sure they are moving, but usually if they are stuck open you can hear the tappets slapping the valves.

Removed plus and compression is strong.engine does not smoke c at all.I've driven it some since I got it..it does have some valve train noise but I wouldn't say it's excessive but this is my first pacard engine to learn so I'm not sure exactly what it'd supposed to sound like.from behind at exhaust I don't hear any skippING or popping.I'm gonna do plug wires first.spark seemed a little intermittent to me .I'll let yall know what I find..thanks...Dan

It's well known to pour a bit of transmission fluid down carb to free stuck valves.mystery oil would prolly do the same.direct path to valves...it was worth a try...it was only a first step.I'm gonna swap around a wire or two and c what happens...thanks!!

As the others have mentioned you really need to do a compression test at minimum. It will give you the generalized overall health of your vehicles engine. From those readings you can then dig a little deeper. like Ross said if both 1 & 2 cylinders are low than its likely a head gasket. But to better pin point after a compression test you could do what is called a cylinder leak down test. What this does is pin point the source of the leak in the cylinders.

If the air comes out the dip stick or oil fill you have ring issues

If the air comes out the carb you have a bad or stuck intake valve

If the air comes out the exhaust, you have a bad exhaust valve

If the air bubbles out the coolant than you have a head gasket issue.

This can all be done with out taking taking the engine apart.

thanks again!i will try the compression test.i took plugs out and ran it,put thumb over spark plug hole.seemed to have good compression but have not done it with gauge.im gonna start simple and look at plug wires although it seemed to be firing ok just laying against the block.really didn't think I had a major issue at first but like I said the car rocks like its running rough but hear no skipping in the back and it runs good on the road although it is a bit cold natured it seems.i can hear some tapping but figured with solid lifters it would do that some.really just started looking into it.but the rocking got me going.then when I pulled the wires and it didn't change engine rpm I knew something was up..ill keep u informed..thank u for the advise..all my other cars something like this has been electrical like a wire or cap.i did notice a couple of the pickups in the cap looked a little worn or burnt..ill let u know!...Dan

Ok..no compression test needed...decided to just put air pressure on #2cyl with plug out of 1.felt air commi g out of 1 from 2...decided blown head gasket.do all agree?prolly rip into it this weekend..I get to order more stuff!!

Yup, the percentages are extremely high that it's a head gasket failure.