Definition of main bearing in US English:

main bearing


  • One of the bearings in an engine on which the crankshaft rotates.

    ‘an inspection revealed that one of the main bearings had failed’
    • ‘We have removed the main bearings and so the first thing to do is refit some new bearings.’
    • ‘The motor locked up on us, and we found that the main bearing holder had come loose, so we had a pretty big thrash to get ready for that round.’
    • ‘The V6 was revised last year with a new intake system for increased performance and aluminum main bearings for improved durability.’
    • ‘The glycol lubricates the main bearings, prevents the water from freezing, and can be separated from the water through heating.’
    • ‘Insert a piece of welding rod or coat-hanger wire into the oil hole drilled in the main bearing.’
    • ‘The main bearings have been designed to be oversize to ensure a very long working life with minimal maintenance.’
    • ‘From the main oil duct, the main bearings are directly supplied with lubricating oil.’
    • ‘If an engine overheats badly enough, the main bearings and connecting-rod bearings can begin to melt and deform.’
    • ‘The main bearing caps are in ferrous material to maintain tight clearances and are integral to the lower half of the crankcase.’
    • ‘As soon as the oil warmed up, it was apparent that the big ends and main bearings were worn and noisy.’