No compression-next move?

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Borrow a leak down tester instead. Then you will KNOW where the air is going.
Well damn. None of the local parts stores has a leakdown tester in stock. You have to buy it. I'll start by borrowing a compression tester just to confirm that mine isn't broken.
 
Does this engine run? If it doesn't run, then your compression tester is probably correct.
 
A spark plug smashed apart and an air fitting welded to it works too.
 
They can drop valve seats holding up the valves, but zero across all? Are you sure the crank is turning? straight plug hemi could see the piston crowns down the hole, right?
 
My buddy'truck did the same thing idling in driveway. No compression,motor spun real fast with starter. Wish I could help but he sold the truck broken .
 
UPDATE: Well here's a new one on me: The cam dowel pin is sheared off and the cam sprocket slipped about 70-80 degrees to the retard side. I think the dowel pin can be replaced, so I'll do that and see if it bent anything. It happened while it was idling, so maybe I dodged a bullet.
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That’s new. Glad you found it! That pin is going to be hard. And press fit. Need to find an old cam and see if it can be pulled out or driven out from the backside.
Thats a new one for sure.
 
If that dowel broke, then the cam BOLT is the problem.
 
UPDATE:
Motor is out of the car.
I have one of those hoses that lets you pump air into the cylinder to hold valves up while you change springs. I loosened all of the rocker arms so there is no pressure on the valves and shot air into each cylinder. All cylinders held pressure! Except for a little leaking past the rings into the crankcase which is normal. I think I may have dodged a bullet! I guess I need to fix the timing chain and do a compression test to see what I really have, but this is hopeful! Advice? Don't want to pull heads if I don't have to. New ARP head bolts cost a lot of $$$
 
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I’m not a G3 guy..... but ARP head bolts for that application aren’t reusable?
 
I had the same thing happen with my son's Scamp. He took it up to the local station to fill. Calls me up, won't start. Pulled it home. Replaced cam and crank sensors. No start. For some crazy reason, I pull the cam sensor and take a peek inside. Looked like the tone ring was going back and forth(front to back). Pull the front cover. Spun the cam bolt out by hand. The gear was loose enough, that with the movement, the sensor didn't pick up. I now loc-tite all hemi cam bolts.
 
UPDATE:
Decided to pull the cam. There is enough general wear to justify replacement, so new cam, bearings, lifters are ordered.
there are slight marks on the pistons/valves but they held air before I removed them. Tell me your opinion of the contact marks:
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I don't know man. The only way to know for sure is to chuck them valves up in a valve grinder and see how true they are.......by the time you do that, you might as well do a valve job. Now's the time.
 
If it were me, I'd mock it all up again and measure valve to piston clearance to know how close they are. Kind of looks like it was kissing that piston for a while, although I could be way wrong on that.
Either way, as RustRatRod said, must at least check those valves.
No matter what, I'm so glad it did NOT have a catostophic failure with more damage. You dodged a big one this time.
 
Looks like fairly substantial contact to me.
I’m with RRR on this one...... pull em out and reface to be sure.
 
lay the heads flat combustion chamber up and fill the chambers with kerosene or similar. if it doesn't leak past the valves you're golden :thumbsup:
neil.
I agree, but Machine shop explained to me why this is dangerous. Valves can be slightly bent, but spring pressure pulls them down flat to seal giving the impression that nothing is wrong. Need to confirm they aren't bent or they will eventually break. Off to the machine shop I go....
 
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