Anybody Ever Seen This Before?

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72bluNblu said:
Chain had to let go fairly late in all that carnage. If the chain broke first the crank sprocket wouldn’t have shed all its teeth. The crank sprocket spinning against the chain that wasn’t spinning (or wasn’t spinning fast enough) stripped the teeth.

If the chain was just really loose, like mismatched parts, it could have skipped when he revved the engine. I’d make sure I checked the cam and valve train really well too though, because the other possibility is that there was too much resistance from the cam gear for the crank sprocket teeth. Which could mean the problem started on the top end.
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That's the plan. The camshaft does seem rather difficult to turn, but it still has all the valves adjusted. I plan on backing all the rockers off tomorrow and doing more inspection.
 
I would also prime the oil pump to make sure it's still pumping. I have had those stupid *** GM pop on pick up tubes fall off in the oil pan. Stopped the motor so fast it shot the distributor right out of the motor, stripped the hold down bolt threads out of the intake. Put a Helicoil in the intake, dropped the distributor back in and it fired right back up but, didn't have oil pressure. When the pick up tube came off the crank waded it up and stopped the crank so fast and popped then shot the distributor out. I always put a tack weld on those pick up tubes because I have seen it too many times. Why they don't thread in like a Mopar is beyond me...freaking GM.
 
plymouth67 said:
I would also prime the oil pump to make sure it's still pumping. I have had those stupid *** GM pop on pick up tubes fall off in the oil pan. Stopped the motor so fast it shot the distributor right out of the motor, stripped the hold down bolt threads out of the intake. Put a Helicoil in the intake, dropped the distributor back in and it fired right back up but, didn't have oil pressure. When the pick up tube came off the crank waded it up and stopped the crank so fast and popped then shot the distributor out. I always put a tack weld on those pick up tubes because I have seen it too many times. Why they don't thread in like a Mopar is beyond me...freaking GM.
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I tack welded the pickup tube and used an all hardened steel Milodon oil pump drive. If the distributor gets driven the oil pump is gonna TURN. lol
 
I think the chain broke first & got caught in the spkt. The momentum of the spinning crank then neatly snapped off all the spkt teeth. I wonder if something initially jammed in the chain or valve gear that caused the chain to snap?
 
Bewy said:
I think the chain broke first & got caught in the spkt. The momentum of the spinning crank then neatly snapped off all the spkt teeth. I wonder if something initially jammed in the chain or valve gear that caused the chain to snap?
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Don't know, but I'm gonna find out!
 
Pos chain seen this before and its the chain that brakes and the rest is history typical cheep crap,dont understand whay people use this kind of parts,just my op
 
plymouth1937 said:
Pos chain seen this before and its the chain that brakes and the rest is history typical cheep crap,dont understand whay people use this kind of parts,just my op
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Me either. Before I took this project on, this kind thing from this guy would have really surprised me. Now, not so much.
 
RustyRatRod said:
Me either. Before I took this project on, this kind thing from this guy would have really surprised me. Now, not so much.
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Bad luck for the car owner to bad but if the valve-piston hasnt collided then your safe,new timing set and on the road again
 
plymouth1937 said:
Bad luck for the car owner to bad but if the valve-piston hasnt collided then your safe,new timing set and on the road again
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Doesn't matter. It's gettin fixed one way or the other. lol
 
If the chain broke first, how did a tooth end up between the chain and the cam sprocket? The tooth broke first, and was carried by the chain to where it sits in the picture (or maybe a lap or two and then where it sits, but at least to where it sits). Also, if the chain broke first while everything was moving at speed, it wouldn't have been just hanging on the cam gear. Assuming the first picture is how Rob found it, the chain had to let go when everything had nearly stopped spinning. Otherwise the rotating gears would have just shed the chain and it would have been wadded up at the bottom of the cover. Also, if the chain got wedged somewhere, there would be a witness mark on the block or the gear where that happened.
 
Has bent valves on both sides. I'm pullin heads. lol
 
72bluNblu said:
If the chain broke first, how did a tooth end up between the chain and the cam sprocket? The tooth broke first, and was carried by the chain to where it sits in the picture (or maybe a lap or two and then where it sits, but at least to where it sits). Also, if the chain broke first while everything was moving at speed, it wouldn't have been just hanging on the cam gear. Assuming the first picture is how Rob found it, the chain had to let go when everything had nearly stopped spinning. Otherwise the rotating gears would have just shed the chain and it would have been wadded up at the bottom of the cover. Also, if the chain got wedged somewhere, there would be a witness mark on the block or the gear where that happened.
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Yup that first picture with the chain hangin on is how I found it. It even swole the timing cover up so I couldn't get the bolts out with a socket. I had to wrench them out with an open end. lol
 
I would bet pulling the intake will tell the tale-cam bearings not clocked correctly?
 
Two bent exhaust, one bent intake.

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Not trying to second guess you but did you pull the distributor and turn the camshaft? No blue spots close to the cam bearings
 
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