Porsche Parts Catalog Porsche Accessories Catalog Porsche Technical Articles Porsche Tech Forums
  Search our site:    
View Recent Cars  |   Cart  | Project List | Order Status | Help    
Get FREE Ground Shipping with the purchase of $179 in qualifying parts!
HomeTech Articles > 356 Valve Adjustment Made Easy

Pelican Technical Article:

356 Valve Adjustment
Made Easy

Difficulty Level 2

Difficulty scale:
Adding air to your tires is level one
Rebuilding a 911 Motor is level ten

Figure 1:
Valve Covers Removed

Figure 2:
Cranking the Engine Using the Alternator Pulley

Figure 3:
Lining Up Top Dead Center

Figure 4:
Piston and Cylinder Layout for 356 Engine

Figure 5:
Measuring the Clearances with a Feeler Gauge

Figure 6:
Tightening Nuts with Angled Wrench

    Proper valve adjustment is critical to maintaining optimum performance in any engine.  If the valve clearances are too tight, then you may be getting leakage out of the valves during combustion.  If they are too loose, then the valves will not be opening all the way, and will also be very loud.  Both conditions can cause minor to serious damage to the engine.   Adjusting your valves is a simple task that can easily be done by the home mechanic without taking the car to a shop.  No special tools are required, and the car doesn't even need to be jacked up in the air.

     Here's what you need to adjust the valves:

  • Large screw driver or crow bar
  • New valve cover gaskets (if old ones are leaking)
  • Feeler gauges (0.006" exhaust & 0.004" intake)
  • Large adjustable wrench
  • 13mm regular or offset wrench

     The first step is to let the car sit until it is completely cold.  The valves can only be adjusted when the engine hasn't been run for several hours.  Once the car is cold, then you remove the valve covers using a crow-bar or screw driver. Put a oil-drip pan underneath the engine to catch the run-off oil when you remove the valve covers.  There is no real exact science for this step, but the covers should come off with a little amount of force applied.  Be careful not to slip or you might scratch the valve covers.  The exposed valves, visible after the cover is removed, are shown in Figure 1.  The next step is to rotate the engine until it reaches top-dead-center (TDC) for cylinder number 1.  Remove the distributor cap so that you can see the location of the rotor. Rotate the engine by turning the generator pully as shown in Figure 2.  There should be a small notch on the edge of the distributor, indicating TDC, cylinder #1.  Once the rotor is in the general vicinity of the notch, line up the crankshaft pully timing mark with the notch directly to the left of the serial number.  This is shown in Figure 3.  At this point, with the rotor pointing to the notch on the distributor housing, and the timing mark on the pully aligned with the notch on the case, the engine is at TDC for cylinder #1.  Now you can adjust the valves for cylinder 1.

     The location and layout of the pistons and cylinders for the 356 engine is shown in Figure 4.  It is wise to check the valve clearances prior to adjusting them.  This may give you an indication that something is wrong.  If you've messed up the order of the pistons, or there is something wrong with the engine, the clearances will be way off, or there will be no clearance.

     To adjust the valves, simply loosen the retaining nut that holds the adjusting screw secure and turn the screw until the feeler gauge fits snugly, as shown in Figure 5.  All 356 engines should be adjusted to the valve clearance specifications listed in the table in the 356 Technical Specifications Section.  There is a special wrench, shown in Figure 6, with a specified offset that makes the job easier.  This offset makes it easier to turn the retaining nut without hitting anything else nearby.  After the clearance is adjusted, back the screw off ever so slightly, and tighten the retaining nut.   Tightening the retaining nut may cause the screw to tighten down on the feeler gauge and reduce the clearance.  Getting the right clearance takes a little practice. Always recheck the clearances after tightening the retaining nut as this procedure will almost always affect the clearances.

     After the clearances are set for piston 1, then rotate the generator pulley counter-clockwise, until the crankshaft turns 180.  The distributor rotor should turn 90 counter-clockwise.  At this point, adjust piston number 2.   Rotate another 180, and adjust piston #3.  Rotate a final 180 and adjust number 4.  The distributor rotor at this point should be rotated 90 clockwise from the TDC mark on the distributor housing.  In other words, rotating the crankshaft another 180 should return the engine to TDC.

     After all the valves are done, it may be a wise idea to go back and check them.  I've often found that I've missed a valve or a clearance was off just a bit after doing all the valves.  When you're happy with the clearances, simply replace the valve covers.  Make sure that you use a new set of valve cover gaskets, if the old ones are leaking.

    There you have it.  It's really quite a simple job.  If you have any questions about the procedure in this article, feel free to drop us a line or give us a

  Loading Customer Comments...

Got more questions?  Join us in our Porsche Technical Forum Message Board, and ask a question to one of our many automotive experts
  Search our site:    

View Cart & CheckOut | Project List | Order Status |  Help    

Recommend this page to a friend...

[Home] [Customer Service] [Shopping Cart] [Project/Wish List]
  [Privacy Statement]  [Contact Us] [About Us] [Shipping] [Careers]

Copyright Pelican Parts Inc. -    DMCA Registered Agent Contact Page