^^^ Not exactly.
The mounts were an ancient design, and should never have been used. Big engines made it worse, and sooner...but even a 283 2bbl would rip them. Not, perhaps from outright torque, but some torque combined with the rubber rotting due to oil saturation from engine oil leaks.
The typical scenario involved a sharp left turn from a stop, or very slow speed. Driver adds some throttle, maybe to get out of the way of oncoming traffic. Engine lifts from both torque, and centrifugal force. The linkage-style throttle control (not a cable throttle control) would pull the throttle open as the engine lifted--adding torque, which increased the lift, which pulled the throttle open more...you get the idea.
The last thing that happened before things got REALLY expensive was that the hose for the power brake booster went taut, and then pulled the check-valve out of the booster grommet. All the vacuum in the booster instantly vented; and now you've got a WFO engine and no power brakes. Grandma didn't stand a chance.
The recall involved NOT installing new mounts (of any design, never mind an improved design.) They ran a cable with just a little slack, around the left upper control arm cross-shaft, attached to a special bracket that bolted to the left exhaust manifold. The defective/broken mounts were never touched--they just strapped the engine down so it couldn't lift very far.
Not GMs finest moment.
Newer vehicles-- before or just after the recall of the older vehicles--got reinforced mounts with a "safety tab" that supposedly interlocked and prevented a torn mount from allowing the engine to lift. I knew a guy with a hot-rod Camaro that would go under his car now and then, to straighten-out that safety tab, because he was beating the hell out of it and it'd distort. The safety-tab mounts were backwards-compatible with the previous mounts, but installing them was not part of the recall.
The wonderful clamshell mounts came later still, and put a real end to the safety situation with the engine lifting. And--bonus--being more enclosed, they didn't get as much oil dripped on the rubber which was a partial-cause of the rubber deterioration which caused the mount to separate in the first place.
The mounts were an ancient design, and should never have been used. Big engines made it worse, and sooner...but even a 283 2bbl would rip them. Not, perhaps from outright torque, but some torque combined with the rubber rotting due to oil saturation from engine oil leaks.
The typical scenario involved a sharp left turn from a stop, or very slow speed. Driver adds some throttle, maybe to get out of the way of oncoming traffic. Engine lifts from both torque, and centrifugal force. The linkage-style throttle control (not a cable throttle control) would pull the throttle open as the engine lifted--adding torque, which increased the lift, which pulled the throttle open more...you get the idea.
The last thing that happened before things got REALLY expensive was that the hose for the power brake booster went taut, and then pulled the check-valve out of the booster grommet. All the vacuum in the booster instantly vented; and now you've got a WFO engine and no power brakes. Grandma didn't stand a chance.
The recall involved NOT installing new mounts (of any design, never mind an improved design.) They ran a cable with just a little slack, around the left upper control arm cross-shaft, attached to a special bracket that bolted to the left exhaust manifold. The defective/broken mounts were never touched--they just strapped the engine down so it couldn't lift very far.
Not GMs finest moment.
Newer vehicles-- before or just after the recall of the older vehicles--got reinforced mounts with a "safety tab" that supposedly interlocked and prevented a torn mount from allowing the engine to lift. I knew a guy with a hot-rod Camaro that would go under his car now and then, to straighten-out that safety tab, because he was beating the hell out of it and it'd distort. The safety-tab mounts were backwards-compatible with the previous mounts, but installing them was not part of the recall.
The wonderful clamshell mounts came later still, and put a real end to the safety situation with the engine lifting. And--bonus--being more enclosed, they didn't get as much oil dripped on the rubber which was a partial-cause of the rubber deterioration which caused the mount to separate in the first place.
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