QUAD 4 (LD 2) ENGINE - HYDRAULIC TIMING CHAIN TENSIONER
Presently there are three types of timing chain tensioners used on the Quad 4 (LD2) engine. All tensioners are functionally similar.
FIRST DESIGN TENSIONER - utilizes an external spring along with the tensioner to assist timing chain tensioning. When servicing the tensioner, this spring and the retaining sleeve need not be reinstalled.
SECOND DESIGN TENSIONER- differs only by not having a spring and sleeve. Both first and second types have a spring pivot post on the tensioner, and the plunger assembly foot is offset. During reassembly of the tensioner, the offset portion of the plunger should face toward the center line of the crankshaft.
THIRD DESIGN TENSIONER - does not have the pivot post and has the foot centered on the plunger assembly. It is utilized as a service replacement for all previous tensioners.
Refer to illustration.
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