bbc valve lash adjustment.
01-24-2009, 07:10 PM
#1
bbc valve lash adjustment. does anyone have a quick tip on adjusting valves on a bbc. its got all standard pieces and a hydraulic cam but im assembling it for a kid and wont have chance to run it or anything before he puts it in and i dont want to have to pull the covers back off.
01-24-2009, 08:14 PM
#2
Quick explaination.
Turn the engine by hand clockwise until you see the exhaust valve just start to open, adjust the INTAKE on that cylinder, then turn it over until the intake valve just finishes closing, and adjust the EXHAUST valve on that cylinder.
To adjust back the nut off until the pushrod is loose. Then tighten it until it just barely has resistance on it. It's a lot easier with the intake off so you can see the lifters, you don't want the plunger of the lifter to go down at all at this point. If it has poly locks it's even easier because you can turn the nut with your fingers.
Once there is no slack between the rocker and lifter, and the lifter isn't pushed down at all, THEN turn it 1/4 to 1 turn. People have their own preference on this but I'd suggest half a turn. This should push the lifter plunger down. Then you're done.
I usually do one side at a time starting at the front cylinder on one side and working my way back, it's more cranking but less chance of losing track of which ones you've done already.
Turn the engine by hand clockwise until you see the exhaust valve just start to open, adjust the INTAKE on that cylinder, then turn it over until the intake valve just finishes closing, and adjust the EXHAUST valve on that cylinder.
To adjust back the nut off until the pushrod is loose. Then tighten it until it just barely has resistance on it. It's a lot easier with the intake off so you can see the lifters, you don't want the plunger of the lifter to go down at all at this point. If it has poly locks it's even easier because you can turn the nut with your fingers.
Once there is no slack between the rocker and lifter, and the lifter isn't pushed down at all, THEN turn it 1/4 to 1 turn. People have their own preference on this but I'd suggest half a turn. This should push the lifter plunger down. Then you're done.
I usually do one side at a time starting at the front cylinder on one side and working my way back, it's more cranking but less chance of losing track of which ones you've done already.
