Thread: setting valve lash

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i am about to bolt the the valvetrain together on my 406. it has solid lifters and i know i am going to need to adjust the valve lash....could anyone help me out with a way to do this...i have no clue and neither does anyone around here...or at least anyone that i trust.

Snarffed this from the Crane Cam site -
I'm sure you'll have more specific replies later today -

-- The following is from the Crane Cams Site
http://www.cranecams.com/?show=techarticle&id=2

Setting Valve Lash on Mechanical Cams

All the valves must be set individually and only when the lifter is properly located on the base circle of the lobe. At this position the valve is closed and there is no lift taking place. How will you know when the valve you are adjusting is in the proper position with the lifter on the base circle of the cam? This can be accomplished by watching the movement of the valves.

1. When the engine is hot (at operating temperature) remove the valve covers and pick the cylinder that you are going to adjust.

2. Hand turn the engine in its normal direction of rotation while watching the exhaust valve on that particular cylinder. When the exhaust valve begins to open, stop and adjust that cylinder's intake valve. (Why? Because when the exhaust is just beginning to open, the intake lifter will be on the base circle of the lobe, so the intake is the one we can now adjust.)

3. Use a feeler gauge, set to the correct valve lash, and place it between the tip of the valve stem and rocker arm. Adjust until you arrive at the proper setting and lock the adjuster in place.

4. After the intake valve has been adjusted, continue to rotate the engine, watching that same intake valve. The intake valve will go to full lift and then begin to close. When the intake is almost closed, stop and adjust the exhaust valve on that particular cylinder. (Again, when we see the intake valve almost closed, we are sure that the exhaust lifter is on the base circle of the lobe.) Use the feeler gauge and follow the procedure described before in step 3.

5. Both valves on this cylinder are now adjusted, so move to your next cylinder and follow the same procedure again. In the future you may find shortcuts to this method, but it still remains the best way to do the job correctly.

i just cant figure out how to actually adjust them bc the rockers are on a shaft with 4 bolts bolting it to the head i cant see how to actually get them adjusted

Tyler the info above is pretty clear. If you set them cold add .002 to the lash setting with iron heads and block. Normal lash setting is about .022-.024 hot depending on the cam specs. What part don't you understand? It may seem confusing at first but read the info a few times and it should be pretty clear. HTH....


G.

You'll need either adjustable rockers or adjustable pushrods.

His 406 is a solid lifter block so the rockers are adjustables.

Good pics Denny!!

G.

ps: I'm working on another avatar for ya. I think you will like it more.[/QUOTE]


Really?? Cool!!

yah i have the rockers in the second picture what should the lash be and how do i check it....can i set it while the motor is on the stand? the rockers are in a box and didnt really look at them before i started asking questions that was my mistake. but not i see where the adjustment comes from. i just want to make sure its done right if it helps my cam is a holman-moody HA-B

ok thank you what do i need to check the lash.....feeler gauges? i have a set of them that looks like a pocket knife will that work also do i have to reset the lash when the motor is hot

do i just put the feeler gauge on the rocker where the adjustment bolt is and tighten it until i get it to .025? sorry im making this so complicated

Add like I said above add .002 to the setting if doing them cold with iron heads. You'll get the feel for it. Denny's right check your cam card or ask Holman Moody what lash settings they should be. You want to be certain you have the correct specs. You'll be a pro in no time.

G.

Make sure the feeler gauge is dirt and oil free as well as the rocker tip and valve stem tip. You should be able to lift up on the rocker tip with your thumb and forefinger at the valve tip to take out the play at the pushrod/rocker interface and insert the correct feeler gauge or stack of gauges with just a slight push. They shoudn't go in loose, but you shouldn't have to force them either. Always use the thickest blades you can make a combination with. For instance, if you were to need 0.025" and there was no 0.025" blade, use a 0.012" and a 0.013" stacked together rather than a 0.020" and a 0.005". The thin blades will want to bend and curl up on you where the thicker blades will hold their shape.

The feeler gauge blades should have just a very light coat of oil on them. Wet your finger and thumb with oil and draw the blades through your finger and thumb to wipe off all but just a very, very light coat of oil, wiping your finger and thumb on a lint-free rag as you prepare the blades. Remove dirt and grit from the rocker/stem tip interface by drawing strips of paper through them as you hold the rocker tip down against the tip of the valve stem. Just cut up some strips of white paper about the same size as the feeler gauge blades. That'll remove all the grit, dust and oil from the interface so you can get a good reading. Be careful when tightening down the lock nut. If you don't have someone holding a tool on the adjusting screw to keep it from turning, it can tighten up as you draw the lock nut down.

Oh yeah, and don't forget to squirt some oil on the valve stem tips before you hit the starter.

Tech VERY good info....i was thinking of a good way to splain it too. You nailed it bud!

Tyler keep us posted how things turn out bud!!

G.

ok guys sorry for all the confusion when i checked this post there were only a few replys the reply that FFR428 posted after SBC never showed up on my computer until today this is weird i checked this last night and there were only a few posts and now there are 2 pages of replys thats most of the reason for all the confusion bc i couldnt see all the replys haha this has been happening for a while on a couple of diffrent forums thhat i use it must be a problem with my computer anyway i think i ore than understand now thanks guys