What could cause this? 360 problems ####update####

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ike61

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here is what i have. 1978 360 E58, stock dished pistons, 587 heads, sealed power 214/224 duration, 443/465 lift. I put engine on my run stand and it wouldnt start or even fire. No compression. Pulled the heads off and the number one exhaust valve was broken. Every exhaust valve hit the piston. The heads were surfaced and i used the thin mr gasket head gaskets. Stock push rods and rockers. Any ideas? This is a pic of the number one piston

1DE95C4B-F8C1-4025-B242-057090E8B182.jpeg
 
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Is your cam timed properly? If your valves open at the wrong time, they could hit the pistons.
 
Simple. Timing chain installed incorrectly.
 
I didnt degree it. I thought i just lined up the timing marks. I must have f‘d it up.
 
ike61 said:
I didnt degree it. I thought i just lined up the timing marks. I must have f‘d it up.
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It may not be your F’up. The tolerance stack up may be enough that dot to dot was retarded enough to hit the exhaust.

Degreeing the cam would have avoided that if that is the case.
 
Cam timing would have to be retarded 40-50 degs for exhaust valves to crash the pistons with that tiny cam.
Valves would have to be damn near fully open, it's virtually impossible for all exhaust valves to be crashing.
 
Rat Bastid said:
It may not be your F’up. The tolerance stack up may be enough that dot to dot was retarded enough to hit the exhaust.

Degreeing the cam would have avoided that if that is the case.
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Timing set could have been mismarked. This is a prime example of why you should degree every stinkin cam. performance or not.
 
ike61 said:
I didnt degree it. I thought i just lined up the timing marks. I must have f‘d it up.
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Bad, very bad, very very bad.
fishmens67 said:
Cam timing would have to be retarded 40-50 degs for exhaust valves to crash the pistons with that tiny cam.
Valves would have to be damn near fully open, it's virtually impossible for all exhaust valves to be crashing.
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I had a Comp 294S installed 4*’s out and the intake valve were so close they didn’t allow the carbon to settle on the pistons. My bad, misread the marks on the gear.
 
anyone ever do a valve drop with Chrysler cylinder head on a table, they drop quite a bit before they contact the table.
Mopars have a ton of valve clearance with factory low compression pistons.
 
rumblefish360 said:
Bad, very bad, very very bad.

I had a Comp 294S installed 4*’s out and the intake valve were so close they didn’t allow the carbon to settle on the pistons. My bad, misread the marks on the gear.
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Had to be during overlap.
 
Rat Bastid said:
Thats when they hit. At overlap.
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Please tell me something I don't know.
also the intake valve chases the piston and the piston chases the exhaust.
The piston is damn near tdc when the exhaust closes
 
fishmens67 said:
Please tell me something I don't know.
also the intake valve chases the piston and the piston chases the exhaust.
The piston is damn near tdc when the exhaust closes
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Right. And if (this is a big IF because cam companies don’t normally give this spec) you know your valve opening at TDC for the intake centerline you use you can figure out it doesn’t take being off very much to crash a valve.

Comp is the only one I know that gives that spec and it’s usually for a 106 and 110 ICL.

Long, slow cams have far less valve opening at TDC than do lobes that are much faster with the same at .050 timing.

And since the intake does follow the piston down the hole, you only need piston to head clearance for intake piston to valve clearance.

That means if you run .040 piston to head clearance and the pistons don’t hit you can run .040 piston to valve clearance on the intake valve. I wouldn’t do that with a timing chain.

Reher-Morrison says the exact same thing except they at .010 extra clearance just for a little more margin.

For the exhaust side, they use whatever your intake valve clearance is times 1.6-2.0 and send it.

That means if you have .050 clearance on the intake valve you need .080-.100 on the exhaust valve.

Most guys run way more than that and it just pisses away compression.
 
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Three key timing set by chance? Circle, square, triangle on bottom gear? Maybe you're out a third of a turn, if assembly went south.
 
I'm no help, but looking to learn.
I can say when we replaced the top end in our 273, that I installed crank gear wrong. Like Max mentioned ours had 3 keyway choices and of course I picked the wrong one lol. A member here Badsport and others here helped solve my problem. Thankfully discovered the issue while engine was on stand. Turned over by hand and it locked up...pulled valve cover and 2 push rods were bent.
Good luck!
Was this an orig stock engine? Or apart previously and worked on?
 
4spdragtop said:
I'm no help, but looking to learn.
I can say when we replaced the top end in our 273, that I installed crank gear wrong. Like Max mentioned ours had 3 keyway choices and of course I picked the wrong one lol. A member here Badsport and others here helped solve my problem. Thankfully discovered the issue while engine was on stand. Turned over by hand and it locked up...pulled valve cover and 2 push rods were bent.
Good luck!
Was this an orig stock engine? Or apart previously and worked on?
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Did you pull the heads and check the valves? If it's enough to bend a pushrod, it's enough to bend the heads of valves. I sure wouldn't proceed without checking.
 
Nope, I didnt reef on it, but was firm. Surprised how "ez" they were to bend lol.
Corrected crank gear, straightened rods and moved on. 10 years and 10k miles ago.
**edit**, I DIDN'T straighten the bent push rods, I out used straight ones in lol. Figured I'd better clarify that:realcrazy:
RustyRatRod said:
Did you pull the heads and check the valves? If it's enough to bend a pushrod, it's enough to bend the heads of valves. I sure wouldn't proceed without checking.
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I checked push rod length. I'm going to pull it apart and degree the cam
 
Did you soak or pump up the lifters before installation? If so they may have been holding the valves open. I'm not sure how that became such common practice but it's not the right way to install lifters. Leave the pushrods out for a while (day or 2) and periodically check to see all of the hydraulic plungers can be pushed down completely. Once they are "free" you can reinstall the valvetrain and try starting it again. Before you do that though (and after degree-ing the cam of course) rotate the engine by hand; if it gets hard to turn STOP and check the lifters again to make sure none are pumped up. Then prime the oil pump while rotating it by hand again and make sure it turns smoothly through 2+ full rotations of the crankshaft.

When I put together my 360 that has a stock 5.9L Magnum short block (no valve reliefs in stock pistons), Edelbrock LA-based heads and a ~.550" lift hydraulic roller cam I had to be careful as some of the factory Magnum roller lifters I reused had somehow pumped up after sitting and those lifters prefer a lot of preload, like .080"-.100" iirc so with the correct pushrod length if they were fully pumped up that would cause the valves to be open an extra .100" or more due to rocker ratio. The piston-to-valve clearance was already on the tight side so when I first went to rotate the engine by hand some of the valves would start to contact the pistons and I'd have to let it then sit and bleed down the lifters, rotate some more, let them bleed down, repeat a few times and then finally they were all where they should be and I could start the engine.

If the lifters don't bleed down soon enough or you want to get it going sooner you can take each lifter out one at a time (so you don't mix them up), take them apart to drain oil out of the plungers and then reinstall. Hydraulic lifters of any kind should not see pressurized oil until they're installed in the engine with the rest of the valvetrain. Better to have it clatter and stumble a bit on initial startup as they pump up than have them hang the valves open.
 
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ike61 said:
I checked push rod length. I'm going to pull it apart and degree the cam
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How much was the head surfaced? if using stock push rods and non adjustable rockers I would think the pushrods would be too long.
 
If the cam is still installed you can do a quick-check without taking the front off.
1) roll the crank around until # 6 piston is at TDC and on what would be it's compression stroke. You can tell this by the fact that the lifters do not move when you shuttle the crank back and forth. If this is not the case, then the cam is NOT in right; go to step 4.
2) Go to the #1 piston. Lay a straight-edge across the lifters. Shuttle the crank a few degrees either way until the straightedge contacts each of the two lifters in at least two places. The straightedge should be about parallel to the deck. Now read the degrees on the timing tab, relative to the TDC mark on the balancer.
3) Assuming the TDC mark is correct, it should be within about 4 degrees of TDC on the timing tab, and the piston should be within a few thousands of the deck, or at least from TDC. If this is not the case, then the cam is NOT in right; go to step 4.
4) Now you are justified in pulling the front off. When you get there,
Make sure the cam-key is installed and the Bolt is torqued properly
 
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