Adjusting valve lash advice please
Drifting
Joined: Dec 2011
Posts: 1,743
Likes: 289
From: Chardon Ohio
One thing to add on the breaker bar method...removing the sparkplugs makes the engine easier to turn. The engine compartment in my 69 is tight, making it tough to get the proper angle and engagement while fighting the fan and everything else. Pulling the plugs is an extra step but makes the engine easier to spin by hand and is worth the effort for me. Aligned with Jebby on the 1/2 turn preload.
Good luck - Don
Good luck - Don
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Remove the plugs, bump the starter, breaker bar on the crank. Feel the pushrod. All you guys are doing it the hard way.
I could set the lash on 5 engines by the time you figure out which cylinder is next in order on your first engine.
You just keep torqueing the snot out of the balancer bolt over & over again, and see where that gets ya.
Remember, its not a Pro-stock engine, its a daily driver.
I could set the lash on 5 engines by the time you figure out which cylinder is next in order on your first engine.
You just keep torqueing the snot out of the balancer bolt over & over again, and see where that gets ya.
Remember, its not a Pro-stock engine, its a daily driver.
Last edited by HeadsU.P.; Aug 29, 2019 at 04:39 PM.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
No. Not recommending the last several post. I was being factious. Do this, do that. Its all the hard way.
But hey, your engine, do as you please.
But hey, your engine, do as you please.
Last edited by HeadsU.P.; Aug 29, 2019 at 04:58 PM.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Running. One bank at a time. Eight oil splash clips.
Loosen rocker. Clack-clack-clack, tighten until it stops. Then 180* with your ratchet. Done! Next!
Loosen rocker. Clack-clack-clack, tighten until it stops. Then 180* with your ratchet. Done! Next!
Last edited by HeadsU.P.; Aug 29, 2019 at 07:10 PM.
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Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Only need one set of 8. Only do one bank of cyl at a time.
Use a 1/2" drive ratchet with a short extension. That will keep your knuckles away from the rockers. Its very easy, simple & accurate procedure. Start at either end of the head. Work your way across. Stop engine when done, remove clips, install valvecover. Do the other side.
Use a 1/2" drive ratchet with a short extension. That will keep your knuckles away from the rockers. Its very easy, simple & accurate procedure. Start at either end of the head. Work your way across. Stop engine when done, remove clips, install valvecover. Do the other side.
Last edited by HeadsU.P.; Aug 30, 2019 at 07:07 AM.
Team Owner
Joined: May 2001
Posts: 87,367
Likes: 1,593
From: Western NY
Only need one set of 8. Only do one bank of cyl at a time.
Use a 1/2" drive ratchet with a short extension. That will keep your knuckles away from the rockers. Its very easy, simple & accurate procedure. Start at either end of the head. Work your way across. Stop engine when done, remove clips, install valvecover. Do the other side.
Use a 1/2" drive ratchet with a short extension. That will keep your knuckles away from the rockers. Its very easy, simple & accurate procedure. Start at either end of the head. Work your way across. Stop engine when done, remove clips, install valvecover. Do the other side.
I agree, but as I mentioned in an earlier post, sometimes the engine runs a little rough, once you begin to go beyond the "zero lash" point, and it might make a "rookie" a little nervous. That's why I suggested just tightening the nuts until the lifter stops clattering, then go to the next one and do the same thing, and when they're ALL at the "zero lash" point, just turn the engine off, and tighten them all 180*, as you mentioned.
One other thing....the "adjusting nuts" on the rocker arms are a "crimped thread, self locking" nut. HOWEVER, if you run them up and down a number of times, they WILL lose the tension on the locking portion of the threads, and they won't adequately lock anymore. If that occurs, and they back off, you'll have to replace the nuts with new ones. Don't go to the dealer for new ones, you'll pay $$$. Sealed Power brand nuts are good, and sold at Advance Auto, Autozone, NAPA, etc.
Drifting
Joined: Apr 2017
Posts: 1,377
Likes: 282
From: Bedford New York
There are multiple ways to adjust the valve lash....the only thing that matters using the static (engine not running) methods is having the lifter on the base circle of the cam.
How you get it there doesnt matter. Use whichever method works for you.
How you get it there doesnt matter. Use whichever method works for you.
lol
Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
Me too.... I just did it today actually.... This method is almost fail proof.... All of those other methods will confuse the **** out of anyone and asking for mistakes.
OP, here you go.... EOIC method. Now they are setting valve lash on a solid roller here, so its a little different then setting a hydraulic to "zero lash plus 1/2 turn" but...positioning the valves are the same method. EOIC.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
I agree, but as I mentioned in an earlier post, sometimes the engine runs a little rough, once you begin to go beyond the "zero lash" point, and it might make a "rookie" a little nervous. That's why I suggested just tightening the nuts until the lifter stops clattering, then go to the next one and do the same thing, and when they're ALL at the "zero lash" point, just turn the engine off, and tighten them all 180*, as you mentioned.
One other thing....the "adjusting nuts" on the rocker arms are a "crimped thread, self locking" nut. HOWEVER, if you run them up and down a number of times, they WILL lose the tension on the locking portion of the threads, and they won't adequately lock anymore. If that occurs, and they back off, you'll have to replace the nuts with new ones. Don't go to the dealer for new ones, you'll pay $$$. Sealed Power brand nuts are good, and sold at Advance Auto, Autozone, NAPA, etc.
One other thing....the "adjusting nuts" on the rocker arms are a "crimped thread, self locking" nut. HOWEVER, if you run them up and down a number of times, they WILL lose the tension on the locking portion of the threads, and they won't adequately lock anymore. If that occurs, and they back off, you'll have to replace the nuts with new ones. Don't go to the dealer for new ones, you'll pay $$$. Sealed Power brand nuts are good, and sold at Advance Auto, Autozone, NAPA, etc.
When torqueing a rocker, the engine may run rough for 3 -5 seconds then smooths out.
l understand your method, but I think you jeopardize the ability to keep the engine running smoothly, long enough to finish the task. Setting one valve at a time means the other 15 valves are fine or close to. With your method 8 valves are awaiting their final position. You may actually hear all 8 clack-clack-clack.
Last edited by HeadsU.P.; Aug 30, 2019 at 06:59 PM.
Team Owner
Joined: May 2001
Posts: 87,367
Likes: 1,593
From: Western NY
Engine running, one valvecover off.
When torqueing a rocker, the engine may run rough for 3 -5 seconds then smooths out.
l understand your method, but I think you jeopardize the ability to keep the engine running smoothly, long enough to finish the task. Setting one valve at a time means the other 15 valves are fine or close to. With your method 8 valves are awaiting their final position. You may actually hear all 8 clack-clack-clack.
When torqueing a rocker, the engine may run rough for 3 -5 seconds then smooths out.
l understand your method, but I think you jeopardize the ability to keep the engine running smoothly, long enough to finish the task. Setting one valve at a time means the other 15 valves are fine or close to. With your method 8 valves are awaiting their final position. You may actually hear all 8 clack-clack-clack.
(it seems that this topic comes up about once a year, and gets more involved, each time....)
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Absolutely. This form of setting valvelash while running is not for a engine on a stand or all-out racing engines or an engine before break-in.
This method is for a street use / daily drivers engine that are not seeking to reduce ET by a tenth of a second.
Setting lash while running got a bad rep early on because of the oil spray, dripping oil on the exhaust, smoke everywhere. Now, there are spray clips to contain that or clever ways to use an old valvecover see post 3.
I just use a long piece of cardboard, two inches high, between the valvesprings and the valvecover ledge, plus the 8 clips. No spray. No dripping. No smoke. Fast, easy, fairly accurate.
This method is for a street use / daily drivers engine that are not seeking to reduce ET by a tenth of a second.
Setting lash while running got a bad rep early on because of the oil spray, dripping oil on the exhaust, smoke everywhere. Now, there are spray clips to contain that or clever ways to use an old valvecover see post 3.
I just use a long piece of cardboard, two inches high, between the valvesprings and the valvecover ledge, plus the 8 clips. No spray. No dripping. No smoke. Fast, easy, fairly accurate.
Last edited by HeadsU.P.; Aug 31, 2019 at 08:50 AM.