Rockers and Pushrods
Original submission by T Feb 18th 2007:
- 1 Saddle Type Rocker Gear:
- 1.1 Overview:
- 1.2 Bolts for Non-Adjustable Valve Gear:
- 1.3 Rocker Saddles:
- 1.4 Adjustable Valve Gear:
- 1.5 Pushrod Lengths:
- 1.6 Reliability:
- 1.7 Rebuild Requirements:
- 1.8 Setting Non-Adjustable Valve Gear:
- 1.9 Rocker Ratios:
- 1.10 Don't Do's:
- 1.11 Lifter Dimensions:
- 1.12 Noisey Lifter Diagnosis And Repair:
- 1.13 Links:
- 1.14 Terms:
Saddle Type Rocker Gear:
The Saddle Type Rocker Gear used in the red 202 and 173 Engines is the same as that used in the later Blue 2850 and 3300 Engines as well as the Black 3300 both Carburettor and EFI Engines. It works in conjunction with Hydraulic Valve Lifters. Whereas the earlier Rocker Gear was adjustable, there is no adjustment for this equipment but it does have to be set up carefully and torqued precisely. Altering the procedure can result in Valve Rattle. The philosophy behind the change is covered under Natural Bearings in Engine Life.
Bolts for Non-Adjustable Valve Gear:
Rocker Bolts can be reused provided they have never been over-torqued .
New Rocker Bolts:
try your local holden dealer , i think you can still buy them new.. PART NUMBER 9423842 ... FOR 12. wombat..
End of submission by Wombat
These must be installed with the arrow pointing towards the inlet manifold on both sixes and V8's.
Adjustable Valve Gear:
Info on setting Adjustable Valve Gear can be found here Hydraulic Valve Lifters.
Submitted by WBJailwagon on Tue, 19/06/2007 - 10:58.
T,Just measured one from a 3.3 Black motor - 9inch (229mm approx),and one from a 186 - 9 1/8inch (232mm approx).
186......9.136" 202......8.976" V8.......8.680" L34......8.906" Shane.
End of submission by HPEngines 173, 202, 2850 (2.8) and 3300 (3.3) all use the same pushrods.
Once the Saddle type Rocker Gear is installed correctly it can run silently and reliably for hundreds of thousands of kilometers without the need for adjustment provided the routine oil changes are observed.
It's always advisable to replace the Hydraulic Valve Lifters Rockers and Bolts at least when doing Head work or whenever Valve train problems have occurred since wear patterns where the Rocker Faces meet the Valve Stems, where the Rockers meet the Saddle Bearings and where the Rocker Arms contact the Pushrods can create undesirable results.
Setting Non-Adjustable Valve Gear:1. Any Rocker Gear work must be performed with the Rocker Cover removed so a new Rocker Cover Gasket is a must.
2. The Side Covers will have to be removed to replace the Hydraulic Lifters so new Side Cover Gaskets will be requiired as well.
3. Removing old Lifters can be a challenge. They sometimes mushroom and have to be hammered out from underneath after removing the Camshaft. I've been able to remove them by "twist lift and lower". Repeat that process with some powerful Multigrip Pliers. It took a long time.
4. Before fitting new Hydraulic Lifters leave them soaking in Oil so that they will fill
up and lose all the air in them. This will save a lot of problems during the initial startup.
The Oil will flow through them faster and minimise the risk of Valve Gear wear. They can also be pumped full of Oil by standing them vertically in a container and pressing the inner plunger
up and down with a Pushrod.
6. Make sure the Pushrods are clean including their centres. The centre of the Pushrod carries Oil up to the Rocker Arms. If it's blocked no Oil will flow and the Valve Gear will fail. Make sure the Rockers have holes drilled in them where the Pushrods fit. The holes allow Oil to flow
from the Pushrods into the Rocker Arms.
7. Next, fit the Rockers, Saddles and Bolts as a complete set in pairs but leave them all with the Rocker Bolts finger tight. Rocker Saddles are marked with Arrows which must point towards the Valves on straight 6 Cylinder Holden Engines.
8. Make sure the Pushrods are centred in the Rocker Arms by rotating the Pushrods and confirming each Pushrod can turn easily.
has both Pushrods sitting equally at the lowest height and start torquing down that pair of Rocker Arm Bolts.
10. The Rocker Arm Bolts should be torqued down to 28 ft/lbs with the Valves in the closed position. Tighten them a part turn at a time allowing each Hydraulic Lifter time to compress.
The Lifter will take about 10 seconds to compress per quarter turn of the Bolt.
11. Rotate the Crankshaft until each Valve pair is closed. One at a time torque the Bolts
down allowing time for the Lifters to settle.
12. After torquing each pair, check to see that each Pushrod can be rotated freely. This will
prove that the Lifter has settled and properly adjusted to nil clearance.
13. If any Pushrod cannot rotate freely when its Valve is closed, and after a settling period,
14. Oil the centre of each Rocker Arm.
15. Perform a startup and make sure that Oil is spurting from the end of each Pushrod into
it's Rocker Arm.
16. Make sure the Engine is firing equally on all Cylinders.
17. After running the Engine briefly, shut it down and make sure that the Pushrods are still free to rotate.
it appears the page linked above is incorrect, it should read: all holden v8's are 1.6:1, all 6's are 1.5:1.
hope this helps.
Each Rocker *must* be returned to its original location and to its original Saddle. If not, the lifter will see a different clearance everytime the valve closes. If the current clearance is wide the lifter will close up. If the subsequent clearance is narrow the lifter will make the valve ride for up to 2 mins.
21.45mm dia, 51mm length.. assuming you meant 6cyl?? Red, blue, black 6 and V8 Engines all use the same Hydraulic Lifters as standard.
Noisey Lifter Diagnosis And Repair:
2. Found the No 2 Inlet Valve had the problem.
3. Confirmed by levering out the lash with a screwdriver between the valve spring and the Rocker Arm. The rattle stopped with each levering and returned when the screwdriver was removed.
4. Shut down the engine and rotated the crank until the troubled valve was wide open. The valve spring held the lifter plunger compressed as we removed the retainer clip from the
lifter. 5. Removed the No 2 spark plug to make crank rotation easier. 6. Equally loosened the rocker bolts on both valves and removed both rocker arms and saddle, keeping everything united. 7. Removed the faulty lifter - lift, tap down, rotate, repeat method. 8. When the lifter was high enough, placed an angled allen key into the lifter oil hole and pulled the lifter out with pliers. 9. Placed the lifter in a plastic bucket so no parts could fly apart. 10. Pressed the plastic tube of a carb cleaner can into the lifter oil hole and blew the lifter pieces apart. 11. The bottom of the inside of the lifter body was filthy with black contaminated sludge. 12. The check valve body was also layered with sludge and looked blocked. 13. Using pliers we levered the check valve off and removed the spring and check valve. 14. With all the parts now in the bucket we sprayed everything down with carb cleaner. 15. we inspected all the parts for signs of wear and found none, which included an inspection of the check valve for
roundness and absence of flat spots. It was OK. 16. We reassembled the lifter leaving it empty of oil so that the plunger could be easily compressed and the retainer clip refitted. If it had been oil filled, we would have had to resort to using the valve spring to compress it as in step 4. 17. Checked the Rockers at the valve end for wear marks and found them acceptable. Had we found grooves it would have been necessary to burnish the rocker faces flat. 18. We refit the pushrods, rockers, saddles and bolts to the engine and tightened the Rocker Bolts finger tight. 19. Ensuring both lifters were in the lowest position we began tightening the bolts a 1/8 turn at a time. 20. Naturally the inlet valve pushrod was easily rotatable because the lifter was empty, but the exhaust valve pushrod could not be made to rotate no matter how its bolt was worked. 21. After a while we opted to continue torquing the bolts equally to 23 ft/lbs. 22. We rotated the crank until the exhaust valve was wide open an let the valve spring compress the lifter for some
minutes. 23. About 10 mins later we again rotated the crank until both valves were closed and found the
pushrod was free to rotate. The conclusion is that the exhaust lifter plunger had not been in the uppermost position
since 1974 and had jammed on some sludge. 24. After the No 2 plug was reinstalled and plug lead reconnected, we effected a start. 25. We flooded the centre of both rocker arms with oil to make sure they were lubed until each lifter was fully primed. 26. To be expected, the empty and repaired lifter rattled profusely, but seemed to quieten slightly every so many 10's of seconds as it filled with oil. 27. After repeatedly bringing the power up to 2,000 RPM and dropping back to idle the rattle reduced because the increase in oil pressure primed the lifter. Oil was soon flowing across the top of both rockers from each pushrod. 28. With the rocker cover back on the job was done.