73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: mizozuman2 on July 29, 2014, 03:07:58 am
-
Alright, so I have the heads back on my engine, torqued to spec.I'm now in the process of lashing the valves.
I'll go and get cylinder 1 at TDC, and lash the appropriate valves all around. Then, I'll flip it on over to TDC 6 and lash the valves for that TDC. here's where my problem occurs. When I get everything done, all the valves I lashed for TDC 1 have LOOSE ROCKER ARMS. Like, they're a few turns of the locking nut backwards away from coming off off the pushrod end loose. Anybody know what could be causing this?
-
when doing it that way, which imo is not the most accurate way, but it works for some!
when bringing 1 to TDC you can only lash the valves for #1. then you make your way through the firing order, so you did 1, next would be 8, then 4 and so on and so forth.
but remember you can only do the intake and exhaust valves which operate on that cylinder.
I personally do EOIC, Exhaust Opens = Adjust Intake
Intake begins to close = Adjust Exhaust
-
Awesome. Thanks! I'll give that a try.
-
Basically what he said....you want to do one cylinder at a time (18436572) with the cam lobes at their lowest point. I personally just adjust to zero lash and that's it. No 1/4 turn or 1/2 turn.....I just make sure my lifters are pumped up good by soaking them in oil, take an old pushrod (with all the lifters submerged in a coffee can) put the pushrod where it should be and then tap it a few times with a rubber mallet. Then once they're in I just spin and jiggle the pushrod as I slowly tighten the rocker nuts until there is no up/down jiggle but I can still spin the pushrod. BUT that's just me......
*Also if you happen to be using "Polylocks" you need to make sure the set screws and rocker studs are oil free (and some use blue loctite) or else they'll back right back off.
-
Basically what he said....you want to do one cylinder at a time (18436572) with the cam lobes at their lowest point. I personally just adjust to zero lash and that's it. No 1/4 turn or 1/2 turn.....I just make sure my lifters are pumped up good by soaking them in oil, take an old pushrod (with all the lifters submerged in a coffee can) put the pushrod where it should be and then tap it a few times with a rubber mallet. Then once they're in I just spin and jiggle the pushrod as I slowly tighten the rocker nuts until there is no up/down jiggle but I can still spin the pushrod. BUT that's just me......
*Also if you happen to be using "Polylocks" you need to make sure the set screws and rocker studs are oil free (and some use blue loctite) or else they'll back right back off.
Thanks a bunch for the input.
-
The "do the lash for half of the valves at TDC then rotate and do the other half" only works with a stock cam.
I have always done the lash on each cylinder by going through the firing order. This way you only rotate the engine through 720°. If you are not on the base circle at TDC then something is really wrong!
The EOIC method, while sound, in my opinion is way too much work! You have to rotate the engine so many times!