B&S 120000 series

Geochurchi

Active Member
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Aug 16, 2021
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Hi All, this engine is on a pressure washer, originally ran out of oil, refilled with clean oil, ran fine for quite awhile until it stopped again, drained oil which was grey in color, when I tried to restart it just seemed to spin freely, I disassembled it, piston and rings seem fine at least good enough that there would seem to be some compressor, any thoughts as to where to look, also it would assume that there should be to be sure the timing is correct if i reassemble it.
See score mark on cylcinder, is this factory?

6a086c76_8b51_4ed1_afc8_b2a65881731e_1484ec26e9f66939431a4c32299c3f46e4f7f398.jpeg


1fc37857_39a7_43d0_9437_eb3fc4630292_129697bfb9769c42319a6b1bbb0c49026c6cf086.jpeg
 

ILENGINE

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Lack of lubrication failure. Basically in simple terms. The cylinder got hot enough to melt the aluminum causing scoring and galling of the cylinder and piston. The area to the left of your circled area and the area on the bottom of the cylinder opposite of the circled area is also damage
 

Rivets

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IL hit it on the head. No need to think about fixing, time to replace the engine.
 

dougand3

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piston and rings seem fine at least good enough that there would seem to be some compressor
They need the cyl wall to generate that compression. As said - yours is ugly.
 

Geochurchi

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Thanks for the replies, I’ll be scraping it, save what I can for future rebulids.
Geo ??
 
Last edited:

amuller

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Sep 23, 2013
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Crankpin looks OK, cylinder walls not. Might be bored oversize for a new piston if you have access to a machine shop.....
 

slomo

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Crankpin looks OK, cylinder walls not. Might be bored oversize for a new piston if you have access to a machine shop.....
Next will be a FlowMaster muffler install LOL. Super mower to the rescue.
 
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