I have a 1973 Charger SE with a 318. It ran with a small surge and a little bit of a humming noise. The carb that was on it was leaking, so I changed it out hoping this would fix the surging. It didn't really change much. I checked the timing. It was a little off, but I got it set and it seemed to be doing a little better. I could hear the timing chain slapping, so I knew I wanted to go ahead and change it. But before I changed the timing chain, it quit running. When I revved it up, it seemed sluggish kicking in. It did backfire a couple of times, but it still ran. The next day, it would not start. It has fire, it has fuel but it won't crank. I did change the timing chain, thinking it may have jumped time, but when I got into it, it wan't even a tooth off. I've replaced the electronic ignition control and the coil. I am wondering if it could have spun a bearing?

 

A good way to check bottom end would have been to turn crank with timing chain off and "feel" for slop or inconsistent resistance. You could try removing plugs and rocker shafts and turn crank back and forth. Please explain "won't crank".

And Welcome.

 

Engined don't usually run very long after spinning a bearing. Usually isn't long, sometimes seconds, sometimes hours, or in a case I'm familiar with, a couple of days. This was the rear main on a Chev 283, long story, I believe it was related to heating due to a 4 speed misalignment problem

How much force does it take to wrench the engine over with plugs out?

Much more likely you are facing poor engine condition due to wear, worn rings, valves, etc. Is there ANY possibility you got the new chain off?

Please define "won't crank." I assume you mean "won't fire."

crank---engine rotates with starter

fire -- engine coughs, tries to run, may run for a few seconds

fires and runs -- engine runs

How GOOD does the spark appear? Did you check spark USING THE KEY to crank the engine or by bypassing the starter relay? This point is important as different electrical paths are used.

Does it backfire through the carb? If so you have the dist. 180* off time.

 

See if the disti will move by hand.It may have come loose and turned.

 

Here is an even more bizarre twist to this. I found a crack in the distributor cap. I went ahead and replaced it. No change. Final step, decided to do a compression test. The 4-6-8 absolutely no compression. 2 had fluctuating compression. One time it had 0 next it had 60 then 110 then back to zero. 1-7 had no compression, 3 had 150 and 5 fluctuated the same as 2. I pulled left side valve cover off. All but two rockers were broken! I am sure when I pull off ride side I will find the same. What would cause this? I don't want to fix this, get it running to only have it do it again. Could a melted down electronic ignition control cause this? I have never seen anything like and neither have any of the local shade trees around me!

 

FIRST thing I'd do is make sure the compression tester actually works.

Then make sure the cam is actually turning, pull the distributor cap and look as you crank the engine. If that is OK, pull the valve covers and watch valve gear action.

 

yes what 440roadrunner said you could have a worn out cam sounds like a time for a rebuild

 

Even if it had spun a bearing The motor would still run !! A bit noisy but it would start.
With broken rockers YOU either installed the timing chain wrong or it jumped time. When you check the compression the throttle needs to be opened

You may have bent valves now..

 

Unfortunately I had alread tested the compression gauge on my 69 Torino - worked fine.

Cam is turning. When I took both valve covers off, I have 4 broken rocker arms and 4 bent rods.

I don't have any problem with a rebuild - I had actually figured it might need one soon.

My problem is that I want to know what caused this problem? I don't want to replace rocker arms and rods and have it do it again. I am thinking before I start breaking down the motor to pull it, I would replace one set of rocker arms and rods, crank it and see if it does the same thing. If not, I would prefer just to be able to replace these.

The motor didn't smoke and seemed to run fine before this problem and I am restoring this car for an extreme penny piching brother-in-law. If it was my car to keep, I wouldn't hesitate to long block it or drop a 440 into it.

 

Sounds like timing chain was off and piston slammed valves !

 

To break the rocker arms something had to hit !! That is the piston hit the valve and bent the valves and the push rods and the rocker arms THE only way for that to happen is for the timing chain to have jumped or installed wrong

 

ON a budget ! 318 heads are cheap ! I would get a set from junk yard and slap them on If you are planning up grades ? Get a set of 4bbl heads/ 360 heads

 

Had friend helping set the timing before I changed the timing chain. I just found out from him that at one point while the car was running, he slipped while twisting the distributor. He said that it retarded it severely - enough that it died. He turned it back, and the car started again, but after that is when it started getting sluggish, then wouldn't start at all. Would this throw the timing off enough to cause this? I would hate to have to strangle the help!

 

I truly don't think that would do. It more like jump time or chain jump !!!!

 

pull it and rebuild it

 

Any ignition timing would not cause this type of mechanical damage. This is a mechanical "timing" issue.
I would remove all front accessories and get a piston stop to verify TDC at crank. With rockershafts off and using pushrods you should be able to see/feel your valve events when the pushrods move as the piston passes TDC.
If cam timing is not easy for you then removal of a head is warranted as bent pushrods can happen from tight valves or loose chain "touching" the valves. Broken rockers can be classed as catastrophic failure and the impact force between the piston and valve would be great .
Removal of a head will show tops of pistons and any bent valves.

 

Somehow I missed that. I agree. OP says the cam is in time, I'd bet it is not.

 

If the timing chain was very loose to begin with A sudden engine stop could cause the chain to jump I would bet the bent pushrods are on the exhaust valves. I had a chain go once, it actually broke a valve in addition to bending all 8 exhaust valves

 

Thank you everyone for all the help. I am restoring this for my brother in law and he decided to go with the 440. I am still probably going to long block this motor for the next project.

I will have to change out the radiator with a bigger one for the 440 won't I?

 

You will need to get 440 motor mounts, a big block trans, should get the factory 26" radiator, if you currently have a 904 (small trans) you will need a new drive shaft too made with the larger 1350 U joints. Plus all the little extras.