I have searched and searched and haven't found a correct answer! I just did the head gasket tonight but cannot anywhere find out how to readjust the valves once I bolt the rocker arm assembly back on! The manual only tells you how to do it after the motor is already fired up and warm. I've already loosened them all and need help! Thanks in advance!
The prefered method is adjusting them when the motor is warm.... far more accurate. For a starting point, set them all about .003-.005 LOOSER than specs. As it warms up that gap will close down a bit. Once it is up to running temp, readjust as needed. This is IF you have solid lifters... if they are hydraulic you take them to 0 lash. (just looked in my old Motors manual)
Thanks! Does it matter what the timing is at/ where the cam is when I adjust each valve and cylinder?
Of course. Each lifter must be set with its respective cam lobe on the base circle. The best way for a novice to do that is to have that cylinder on TDC of the compression stroke. Then go thru the firing order, rotating the crank to bring each cylinder up to TDC.
If you have hydraulic lifters, it is not enough to set them to zero lash. The internal piston of the lifter must be depressed, via 'valve adjustment', a specified amount for the hydraulic lifter to function correctly. The adjustment screw thread moves a certain amount per revolution, depending on the thread pitch. I feel certain this procedure is covered in the factory workshop manual. If you don't have hydraulic lifters in your engine......never mind! Ray
Try setting the crankshaft at TDC and adjust all the valves that are closed. Turn the engine 1 full turn and adjust the others. They should all be adjusted about the same amount. If you see an adjuster that is way higher or lower check that one again. If you want to be pernickety you could set the crankshaft at TDC and adjust #1 cyl if both valves are closed. Then turn 1/4 turn at a time and adjust each cylinder according to timing order. Adjust once you get the engine running, then after 100 miles retorque the head and adjust again. The final adjustment should be done HOT after the engine has run for 1/2 hour.
The Buick straight 8 has a procedure like nothing we are familiar with today. If not followed the engine will never run "quite right."
Be persnickety, and do it this way. The firing order of a Buick Straight Eight is 1-6-2-5-8-3-7-4, so you want to set cylinder #1 at TDC with both valves closed, and adjust them. They turn it 90 degrees and adjust the valves for cylinder #6, and so on. Also, make darned sure that the oiling groove on the ball stud is at least halfway down into the rocker arm so that oil can get to the ball/socket interface between the rocker and pushrod. If they're not, you're going to have a lot of squeaking after the motor runs a while. Solid lifters and hydraulic most definitely have different adjustment requirements. Click this link for details of each type: http://www.buicks.net/shop/reference/l-8_valve_adjustment.html
You don't say if you have hydraulic or solid lifters. It makes a difference. Check your PMs. Valve setup is a rather involved procedure according to manual information I have. I could post it here but I find some people tend to disbelieve things they are not already familiar with. Even when given manual references.
Thanks! Does it matter what the timing is at/ where the cam is when I adjust each valve and cylinder? The URL from Ebbsspeed answers your question with the same information I have. My other stuff deals with proper timing & picking the right mark on the flywheel.
The Jalopy Journal
