Remove valve covers . Turn damper to tdc. See if #1 is still #1 and distributor location is #1. Then remove timing cover sounds like chain jumped.

Yes, get back with us ASAP!

Agree!

My first thought,,,especially with the piiiiiinnnggg followed by engine barely running,,,however not certain why drop of oil pressure,,,,except if timing chain totally sheared,,,which is possible after a few additional turns of the engine.

Doubt that a single failed rocker/pushrods/lifter would cause the few moments of excessively poor performance before shutdown, but could cause loss of oil pressure if lifter popped out I guess.

they could if the valve broke or went thru the piston...ask me how I know. Here I'll just show you. And this was at 3000rpm at most...

Sure sounds like what happened to the 440 in my '70 Bee a few months ago on the way to a car cruise. I knew I was in trouble when I pulled the #7 spark plug and found the tip smashed. To say I'm NOT happy with 440 Source heads would be the understatement of the century... Small hydraulic cam and under 6k RPM. In my case, the #7 intake locks pulled right through the retainer. The head is now a paper weight. The #7 piston (SRP forged) has the valve embedded in it. Twisted the "6 pack" rod slightly and the bore is cracked.

Mine were expensive Diamond 11:1 pistons and very ported 516 heads. The guy who built the short block didn't knock the rear cam plug in far enough and the cam "walked" that started a chain reaction that resulted in the #4 intake valve to go thru the piston, rip the cylinder wall, then it sucked pieces over into #1 (I think) beat up that cylinder and wall...oh yeah and fill the oil pan with antifreeze. At least I wasn't at the stripe going 120+ this happened on the way to the track.

Rear cam plug just keeps oil from pouring out of block, does not support cam at all. Just sayin'.

Agreed. THe thrust surface is on the back of the cam gear.


To the original post, any news?

Here's the latest. Install the new high volume oil pump and spun if ccw with drill. Oil pressure read 70lbs. Took off the valve covers and turned the engine with wrench and socket on crank bolt. Turned free. No push rods looked damaged, nor did valve springs or rockers. (I have original max wedge rockers for what it's worth.)

I rotated the motor and confirmed all of the rockers went up and down completely without a problem. So put back on valve covers and took out all spart plugs.

I run NOS...

Found to spark plugs with partial melting of the spark plug tips. Also, to back most spark plugs were completely wet and one fouled with oil inside and out.

Changed spark plugs, gapped to .38 and tried starting motor. It would almost start and then backfire spitting gas through both carbs.

As an FYI I was not using NOS when the motor stopped running right and lost oil pressure.

Next step I guess it to do a compression test. If that passes I'll have to find someone local in Los Angeles to try and set timing as I'm guessing I messed it up taking distributor in and out and oil pump drive shaft.

Anyone else got any thoughts on what could be wrong?? Perhaps cracked pistons??

BTW, someone had asked at what RPM it went bad. It was around 6000 RPM. I beleive my MSD 6AL rev limited is set to 6500. I have rev'd it to this RPM for many, many years without issue. I starting to guess it'll be one or two pistons gone bad #8 and #7 spark plugs were very wet and #7 had oil on the inside and outside.

And/or the timing chain (which is a double roller for what it's worth) jumped as people have suggested OR the single bolt cam bolt sheared off. IF it sheared off would things still rotate fine??

Sorry for my engine ignorance. I'm pretty good at tearing it down, but finding TDC, etc. and I haven't a clue. :-(

Finding top dead center is easy, look at the harmonic balancer. Rotate the engine with the #1 spark plug removed to 0,you should feel or hear the compression, if none rotate around again to 0 the compression stroke. remove the distributor cap and see where the rotor is pointing. It should be pointing to #1 . If you didn't replace the oil pump drive in correctly it could be off causing starting problem . If the rotor is not pointing at #1 remove the distributor and look at the position of the distributor slot in the oil pump drive . The slot must be facing straight front to back of the engine. if not use a long screw driver to rotate the drive to the proper direction, [ rotate the drive not the engine ] then replace the distributor, The rotor should now be pointing to #1.

(1) With the plugs out for easier turning & with a 1&1/4" socket/short extension/breaker bar turn the dampener either way whichever is closest till the slit is at TDC (zero on the timing tab). (2) Then turn the dampener a bit (CCW) from that TDC position till the nearest tooth which will actually be going CW and it is now lined up dead even with the magnet (actually I'd take the tooth past the magnet then come back to it-(chain stretch) till its dead even. (3) at that point see if the rotor is pointing to or pretty close to either the #1 or the #6 dist cap terminal (4) also see where the dampener slit is on the timing tab IE 15 BTDC. Holler back

well somehow the cam walked.

OK, motor problem STILL not identified. Here's the latest info.

Did a dry compression test on all cylinders today with all spark plugs removed and throttle wide open. Here is the results:

Cylinder # Compression seen
1 170
2 179
3 170
4 161
5 169
6 180
7 150
8 152

Engine with new oil pump has almost 70 pounds of oil pressure.

More and more I'm thinking the issue maybe the chain jumped and the timing is all out of whack. We will use top dead center tool to check timing next weekend.

Any new thoughts? Are my cylinder pressures OK for a street motor (that sees some strip) with likely 40,000 miles on the rebuild?

Then you had a problem elsewhere because the cam doesn't even touch the rear plug.

Odd that the back cylinder on each side of the block are both 20 psi less ? or is that 7 and 8 2 cylinders side by side ?

What are you using for head gaskets ?

I don't think any of this cam walking is suggestions on my mystery problem, right?? I'd aprpeciate any feedback on my recently posted compression results above. Thanks!

Yep, agreed. Those are cylinders on oppostite sites furthest back by the firewall. The #8 showed some oil on the inside of plug and the plug is new. All the plugs stink of gas.

And I recall the head gaskets were Felpro. I can try and confirm that and the thickness as have the engine shop receipt from installing the heads I have on it now from several years ago.

No it doesn't,

you seem to be new to moparts, it's not unusual for a thread to be derailed or for someone to ignore your question and instead tell you what you should do even if you didn't ask.