adjust preload on 455BBB ? I have adjusted valves with sequence: as --opens set---as--closes set-- all were solid lift motors. Does this sequence hold true with hydra lic lifterBBB w/roller rockers? 413TA motor please fill in the blanks!! Thanks Kenny462
I always adjust hydraulic lifter preload much like you mention: as the exhaust just opens, I set the intake; when the intake is half closed (on the way to closing), I set the exhaust.
There are a number of procedures that will work, here are 2 more. You can also start at TDC #1 compression, and mark the balancer at 90* increments. Adjust #1 and then move the crank 90*, adjust #8, then 90* and follow the firing order around, 1-8-4-3-6-5-7-2. You are adjusting each cylinder at TDC firing, and both valves are closed.
Hydraulic camshaft up to about 320 degrees advertised duration. Crankshaft in ANY position. Does not matter where it's at: 1. Loosen all rockers so they have play. 2. Tighten all rockers so they are at "zero lash"--the point where all the free play is gone, but no preload on the lifter plungers. 3. Turn crankshaft EXACTLY one revolution 4. Some rockers will now be loose. Tighten ONLY the loose ones to "zero lash" again. 5. Tighten all rockers "your choice" of preload. On Chevies, factory spec is one turn of the rocker pivot nut. Many folks use 1/2 turn instead. Your preload adjustment varies with the method of adjustment used. 6. Put valve covers back on. 7. Have a beer. You're done.
This is the same sure fire way I set both mechanical and hydraulic tappet lash/preload as I was taught by "Fast Fred Catlin" more than 30 years ago. Never an issue and have done countless that way. Larry
Same here, so simple I'm not sure why people want to make rocket science out of it! Chart, we don't need no stinkin chart! Bob H.
