I just had a 318 skip 1 notch and it would run, when I did try starting it turned over way to easy with the starter winding up way high which was an clear indicator since I lost compression and I put a new one in and got lucky w/mo burnt valves

Back to basics...compression test 1st,spark plug condition check , firing order, distributor cap,rotor check,spark plug wire check for ohms,check for spark at each plug..not just 1..gas flow and volume..

This^ Plus check the relationship of the harmonic balancer timing mark relative to #1 cylinder tower on the firing stroke.It should be close to the tower,if not the chain jumped or is severely worn at minimum.

With a 1&1/4" socket/breaker bar slowly bump/hand turn the crank so the timing mark slit on the dampener is coming up to the TDC (zero) mark on the timing tab & stop when the points "just" open (use your test light) & note the dampener reading at that point. EDIT Say your initial was "15" so that is what you would get (or very close to 15) if no damage (that'd be your normal timing). If it has jumped a tooth you will be way off from 15. You could divide the # of teeth on the crank sprocket into 360 to get the # of crank degrees it would off from 15 if it has jumped a tooth (& the wear as mentioned would exacerbate that # even further). Holler how it turns out.

over the weekend, I rented a compression tester from Oreily's.

got the following results (partial):

cylinder 1: 100 psi
cylinder 2: 50 psi
cylinder 3: 95 psi
cylinder 4: 105 psi
cylinder 5: 120 psi
cylinder 6: 100 psi
cylinder 7: unknown, can't get to it.
cylinder 8: 110 psi.

when i removed plugs, both spark plugs on cylinder 7 and 8 are soaked with gasoline. I probably flooded them when I was trying to start by keeping on tapping on the gas paddle.

so, based on the above information, what you guys think?

thanks so much for voicing your opinions, all appreciated.

If you are sure you got accurate readings on 3 & 5, you've got a problem. Next step could be a leak down test to see if it's leaking compression pat the valves or rings, but either way, it's time to break out the tools and start taking the engine down.

Could be blown head gasket since you have low compression on two adjacent cylinders.

taking the heads out would be my absolutely last resort.

anything else I can do/try before embarking on such a big project?

you could try pulling plugs on those and squirting oil down the cylinder then cycling by hand slowly.
if what you say is accurate, you could have washed out the cylinders with too much gas pumping.

but that also means you should probably consider replacing the oil in the engine as well.
check the level and smell it. if it smells like gas, replace it as well.

Redo the compression test, but if cylinders 3 & 5 don't come way up, you have a problem.

I'd be more worried about cylinder 2 and not 3.

He doesn't have low compression on two adjacent cylinders. 3 is a touch low but within guide lines. Cylinder 2 and 5 are the issues and they are not adjacent.

There may be an issue with #2 and #5 "but" ,it still should run,pull two wires on a running engine,it will miss but still run !

My bad. Old eyes saw it as 3 not 2. So ignore the comments about adjacent cylinders. Still a big problem though. Other poster is correct: it should start but it will not run good at all.

sorry, my bad. I re-tested #5, compression is 120.

So here is result of the new test (sober test, didn't drink any beer this time).

cylinder 1: 100 psi
cylinder 2: 50 psi
cylinder 3: 95 psi
cylinder 4: 105 psi
cylinder 5: 120 psi
cylinder 6: 100 psi
cylinder 7: unknown, can't get to it.
cylinder 8: 110 psi.

A pop out the exhaust would tell me the exhaust valve on the cylinder with 50 PSI is the problem.

1st thing I would do is verify all the rocker arms are moving and the valves opening. It could be a wiped cam or collapsed lifter....If that is good then check your timing relationship between the distributor and the balancer.

1 way to verify crank/cam timing is to find TDC on Compression Stroke. Line up balancer line and zero on the water pump tag. Then see if the rotor tip is pointed at #1, if so, it is not timing chain.

even compression is as low as 50, it still should start, right?

Yes





Agreed, 1000%

Always, ALWAYS start with the basics.

Do you have spark? if so,,,Good, If not, why not ?
Pull the air cleaner and pump the throttle while looking down the carb, See fuel spraying? if so, Good, If not, why not?

But based on your initial post.
My gut says the timing chain jumped

Not if the timing chain has jumped a tooth or two
I had that happen on a early (1959) poly 318 truck motor, I started it up in the winter, went to back up and it tried to stall and backfired through the carb. It restarted but didn't have any power after that due to the timing chain being worn out and it had jump a tooth retarding the cam timing
The fix was to replace the timing chain and gears with new ones, which it sounds like you need to do also
Get some good help or take it to a good shop to have it tested and fixed properly

Timing chain jumping should affect all cylinders, not one or two, unless it put a valve into a piston then you'd have zero.

I had a timing chain jump on me when turning the engine by hand while priming. I heard it and couldn't understand at the time what really happened. That engine would not stay running until I resolved the problem.