How do I know if I spun a rod bearing?
If the oil light on the car dashboard goes on, then this might indicate a problem with a rod bearing. This is because a spun rod bearing, i.e., a loose bearing that rotates independently of the connecting rod and the crankshaft, seals the oil holes on the crankshaft.
What happens when you spin a crankshaft bearing?
A spun bearing is bad news because it usually seizes itself around the crankshaft journal. What happens next depends on the bearing’s location. Spun rod bearings are the most common failure. A spun rod bearing will tear up the big end bore in the rod, ruin the rod journal on the crankshaft, and sometimes break the connecting rod.
What should I do if I have spun bearings in my engine?
If an engine has suffered a spun rod or main bearing, and the engine is rebuildable, it will require resurfacing the crank journal, possibly re-machining the main bore or big end rod bore (or replacing the rod) depending on the damage that has occurred.
Can a broken main bearing cause an engine to fail?
That’s really bad news because a broken rod flailing around inside an engine can obviously do a lot of damage! A spun main bearing will tear up the main bore in the block but rarely will it cause the crank to fail. The damage is usually limited to the main journal surface on the crank and the main bore housing.
How is crush fit determined for engine bearings?
To accurately determine crush fit, bearing manufacturers use a special block gauge to measure the bearing after it has been installed in a bore with a known size the cap has been torqued down to specifications. If crush fit is correct, the bearing will be held snugly in place without too much deformation that could cause clearance problems.
If an engine has suffered a spun rod or main bearing, and the engine is rebuildable, it will require resurfacing the crank journal, possibly re-machining the main bore or big end rod bore (or replacing the rod) depending on the damage that has occurred.
Why does my crankshaft make noise when I spin a rod?
This is because a spun rod bearing, i.e., a loose bearing that rotates independently of the connecting rod and the crankshaft, seals the oil holes on the crankshaft. The result is less oil between the bearing and its cover, resulting in metal-on-metal contact. This is why spun rod bearings also cause noise.
That’s really bad news because a broken rod flailing around inside an engine can obviously do a lot of damage! A spun main bearing will tear up the main bore in the block but rarely will it cause the crank to fail. The damage is usually limited to the main journal surface on the crank and the main bore housing.