Valve adjustment

(Difference between revisions)

Revision as of 22:59, 5 January 2008

1. Adjust valves 0.013 in cold
   • No. 1 TDC: Adjust valves 1,2,3,5 (counting from front of engine)
   • No. 4 TDC: Adjust valves 4,6,7,8

From the 1973 Nissan Factory Service Manual:

• COLD: 0.25 mm (13 thousands inch)
• HOT: 0.35 mm (14 thousands inch)

NOTE: The 1971 manual has the cold specification incorrect.

If you are setting the tappet adjustment you should be able to put the timing mark at TDC and adjust four of the tappets then rotate the crank once back to TDC and adjust the other four. Details are below.

Helpful Picture

Procedure

1. Block the wheels, set the handbrake, and put the transmission in nuetral
2. Remove the Rocker cover
3. Turn the engine to the TDC mark. It's easiest to turn clockwise, but you can turn it either direction.
   • TIP: It is very easy to turn if you remove all four spark plugs, but this is not strictly necessary
4. Wiggle the rocker arms. At the TDC mark, either the first two rockers will be slightly loose, or the last two will be. Adjust the four loose ones.

   Either

   • valves 1,2,3,5 (counting from front of engine)

   or

   • valves 4,6,7,8

   

5. Rotate the engine one full turn, again to the TDC mark
6. Adjust the other four loose ones

ADJUSTMENT - Use a feeler gauge:

• You want it to just be able to slip in.
  • If it is a loose fit, tighten the rocker stud (straight screwdriver)
  • If it is very tight, very difficult to slip in, loosen it a bit
• After re-tightening the locknut, check the clearance again

TIP: You may need to do this several times on each 
rocker before getting the hang of it. This is normal.

Check for success: After replacing the rocker cover, Start the engine. Success is:

• Valves are quiet (no ticking whatsoever)
• Engine idles smooth

Parts

No parts are needed. Usually you don't need a new rocker gasket, unless it breaks coming off. Most A-series rocker gaskets last forever.

Do not overtighten screws for rocker cover. Just finger tight.