Timing Chain

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The Timing Chain drives the Camshaft.

Also see: 
* Timing Cover
* Crankshaft Pulley

Overview

We have seen a couple of single link timing chains on A12, which is the original A10 single row chain. Insist on the factory specified double-chain, like Nissan did for later A10s.

NOT GOOD - early A10 single-row chain

NOTE: A rattle can be the trait of a stretched timing chain. Pinging/pinking has also often been mistaken for timing chain rattle

A-series engine has a short timing chain -- and with an automatic adjuster -- it rarely stretches or goes bad.

Compare to the loooooong chaing used in the Nissan KA24E engine:
click

KA24 often has timing chain problems

Replacement

Alignment

Check the cam gear alignment. It should be exactly like this:

If it is not, see Camshaft#Timing.

Part Numbers

The timing chain kit (timing set) includes: Cam, Crank, Chain, Tensioner

KIT SET
* CLOYES Part # 94054S RockAuto.com $35.79
  
* CLEVITE/PERFECT CIRCLE Part # 92602
* ITM 05390500 RockAuto.com $32
  

Cam Sprocket

38 tooth Cam Gear (timing gear)
* Sealed Power 223478 $3.50
* ITM 50022 $4.67
* ITM 50021 $4.67
* CLOYES Part # S47 RockAuto.com $9.41
  
* Beck/Arnley 0250282 $10.85
  

Chain

Same as SRL311 with U20 engine (for Jackshaft)

CHAIN RockAuto.com
* CLOYES Part # S478 $9.40
* CLOYES 94054 $9.70
  
* BECK/ARNLEY Part # 0240226

* ITM 2354 $7

specs
Links: 54
Pitch: 3/8 inch
Rollers: Double
Timing Marks: 2

Crank Gear Key

Same key is used for the engine crankshaft pulley. See Crank Pulley Parts.

Tensioner

* CLOYES Part # 95005 RockAuto.com $3.90
 
* ITM 60004 $6.37
  

Crank Sprocket

19 tooth Crankshaft Gear (Timing Crank Sprocket, Timing Crank Gear)
RockAuto.com
* CLOYES Part # S477 $8.87
  
* Sealed Power 223477 $6.17
* Beck/Arnley 0250258 $7.36
  

USA

B110 RAW LIST
VALVETRAIN
13024-H8500 SPROCKET-CAMSHAFT
13024-18001 SPROCKET-CAMSHAFT
13082-18000 BOLT-CAMSHAFT SPROCKET
13030-18000 WASHER-CAMSHAFT
08915-2401A WASHER-LOCK
08915-14010 WASHER-LOCK
13028-18001 CHAIN-CAMSHAFT
13070-18001 ASSY-TENSIONER CHAIN
08120-63510 BOLT-FIXING CHAIN TENSIONER
08915-13610 WASHER-LOCK FIXING CHAIN TENSIONER
PISTON, CRANKSHAFT & CONNECTING ROD
13021-H1000 SPROCKET-CRANK A12
12316-30000 KEY-WOODRUF 5X16 2 A12

Adjustable Cam Gear

Fitting an adjustable Camshaft gear lets you fine tune the timing. The cam vendor's recommendations are usually best, but retarding the cam a degree or two will generall shift the torque curve higher up in the RPM range. Advancing the cam will (usually) lower the power curve a few RPM.

Adjustable gears come in a few basic kinds:

• Multi-key. Rollmaster had one with nine adjustible keys in the crank sprocket
• Multi-hole. Using different holes
• Variable: Slotted holes allow a continuously variable range

Tomei

Rollermaster