EarnIt

Is it better to adjust valves with engine running or to adjust them with it shut off ? If adjusting with it running do you back them off until they start to clatter
and then tighten until the clatter goes away plus half a turn ? Thanks for any replies.

john73bb

Heres the tech article by Lars, this should answer your questions.
http://www.corvetteforum.cc/techtips...=116&TopicID=3

Follow Lars' instructions and you can't go wrong.

kenincanada

the easy way is go to the wrecker ,get a valve cover,cut the middle section out[keeps the oil from fling around] warm up the engine .sory bolt that cover on the bank your adjusting .fire it up back the rocker off till you hear it tic then slowly tighten down three quarters of a turn. do each one then move to the other bank

tsw71

Doing this with the engine off is NOT the way to go, in my humble opinion. Not only does it turn a 3 minute job into a 1/2hour(or more) job, setting by feel while twirling the pushrod is way too subjective when dealing with a hyd lifter that collapses under pressure. This is fine for initial setup on a new motor or when you have had to remove the rockers for one reason or another, but doing it with the engine running is simply the fastest, easiest and most accurate way to do it when doing a final adjustment. I don't even bother to use the cut out valve cover anymore.I just do the adjustments and clean the engine when I'm done.

kenincanada

yes but that can be messy

tsw71

Agreed, but trying to find my cut out valve cover in my pile of stuff in the shed is even worse :D

With my current S/R torquers, the raised rails around the valve cover gasket area prevents oil from going everwhere. Before I had these heads, I would sometimes grab some foil from the kitchen and build a sort of raised rail out of foil. This is very quick and easy and worked well too, even with my high volume oil pump.

kenincanada

I was tired of getting shot in the eyes with hot engine oil

tnt76vette

One more reason I LUV this Forum: Just bought a set of roller rockers from Bence13_33 and was going to post a Q abt the best way to put them on correctly. I saved Lars article in my 'puter and will bring it up when I install them . This place is the BEST :D :D :D

VegasJen

o.k. i'm no lars but i've always been skepticle of the "dry" method and here's my reasoning: as lars pointed out in his tech article, oil pressure provided by the running oil pump is what takes the lash out of the hydraulic lifters. so if your engine isn't running it seems to me that your lifters have had a chance to bleed down that internal pressure. now if that is true, when you adjust your lifters, you would be adjusting them at the bottom of their stroke preventing them from ever "pumping up". now, i could be wrong about this and if so, please correct me (i love to learn).
in the meantime, i will continue to adjust my lifters with engine running. for those of you who do this, 1)you can by oil deflector clips to prevent those hot spurts of oil in the eye. 2) always be careful of your socket, i recommend a 3/8" drive short socket. if you use a deep well socket or one for a 1/2" drive, there is a possibility of binding the socket and rocker arm as it moves if you don't keep the socket parallel to the stud. that can break a rocker arm stud and that is a bad thing. one more tip if your interested, next time you change out that old, moldy shower curtain-throw it in the garage and put it under your car for your next lifter adjustment. your wife will love you for it! :cheers:

tsw71

There was a debate on this very subject not too long ago.
http://forums.corvetteforum.com/zerothread?id=171185

The post made by Tom454 in this archived thread details exactly why the engine off method is not recommended for final adjustment. Can it be done with the engine off? Yes. Will it be done right? Maybe, maybe not. Read the article and decide for yourself.

Tom :cheers:

nunus79

:D (j/k, I always wanted to do that)

engine not running method, is the only way to get the motor up & running, so you got to know it & got to do it. engine running method, should be done as the final adjustment. Besides allowing close & accurate adjustment, the engine running method gives you the opportunity to inspect your valve train while in operation & check on proper valvetrain lubrication. You can actually check some valve train problems by shooting your timing light on the exposed valve train and reving the engine. Anyway, that's my 2 cents.

What I really wanted to post was to caution everyone about the assumed 1/2 to 1 full turn past zero lash. Although it may be correct for standard conventional hydraulic lifters, I was surprised to see many high performance cam & lifter packages that come with anti pump-up hydraulic lifters. Seems a lot of us have or will be upgrading to hi performance cams. ANTI PUMP-UPs should not be run with 1/2 to 1 turn preload. Zero lash is what the manufacturers recommend. To get zero lash or damn near close on hydraulic lifters, the engine running method is the best, easiest , and only? way that I know how.

If you don't know what kind of lifters you have and need to adjust the valves, the engine running method will quickly show you if you have conventional or anti pump-ups. When you start preloading the lifter with anti pumps, the engine will start bucking or run rough. Conventionals will allow the preload without a hiccup.

Make sure you know what kind of lifters you are running before you do the engine not running method!!!!!!! That's all.

:seeya