气门杆间隙过大会加速气门的积炭。

Excessive valve-stem clearance speeds up valve deposits.

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气门过热或遭受重载（气门杆间隙过大或爆裂）均可造成气门破裂。

Valve Breakage. Any condition that causes the valve to overheat or to be subjected to heavy pounding (as from excessive tappet clearance or from detonation ) may cause valves to Break.

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柴油机横臂导杆折断会带来严重后果，经分析认为其折断原因有：同名气门杆顶部不齐；调整螺母松动，调整螺钉窜动；气门导管与气门杆间隙量大。

The reasons are: different top heights of valve rods having the same names; loose adjustment nuts or adjustment screws moving; and big clearances between valve guides and valve rods.

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