GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 7 of 7

Thread: How many turns?

  1. #1

    Default How many turns?

    I have a 1990 305 silverado with 360,000 on it. I have really tall gears and 700r4.
    Engine is dying gracefully but had to free up a lifter. Now my question to persons
    with experience is how many turns past 0 lash on a healthy geriatrics motor?
    I have heard everything from 1/2 all the way to a healthy full turn!
    I would like to complete this as soon as I receive a response.... Hate walking Thanks

  2. #2

    Default

    I usually go 1/2 for higher-performance apps, or 3/4 for everyday driving.
    Since you've got 360K miles, go with a 3/4 turn.
    ...
    ....

  3. #3
    Master Mechanic daddytech's Avatar
    Join Date
    Mar 2008
    Location
    Portland TN
    Posts
    672

    Default

    never really had one "THAT" tired lol closest i have gotten is the 269,000 that's on my 1989 silverado and i just reset all of those to zero lash and it's fine.

  4. #4
    Jr. Apprentice
    Join Date
    Aug 2010
    Location
    Channahon, IL
    Posts
    14

    Default

    Wow...some go further than necessary. You require .030" lash setting assuming you are using hydraulic lifters. That equates to 1/4 to 1/2 turn. Any more causes valves to float; any less will create valvetrain noise. This is your basic rule of thumb. If you are having problems, though, you shouldn't hesitate to replace the lifters. And make certain that you add ZDDP to the oil. Flat tappets are unfortunate victims of today's oil. If it's a performance cam, you should also remove the inner valve spring for breaking-in the lifters. If it's stock, you should be alright. Best of luck!
    440 HP 383 + 150 shot = fun weekend!

  5. #5

    Default

    lildino, zero lash isn't achieved when you turn it until the ticking stops. It's achieved somewhat after that. The factory setting on that 350 is more like a full turn, but I usually recommend a 3/4 turn if the engine has a lot of miles. Plus, it cuts down on wear substantially.

  6. #6
    Jr. Apprentice
    Join Date
    Aug 2010
    Location
    Channahon, IL
    Posts
    14

    Default

    I'm assuming you are setting the lifters while engine is running? Messy. Overloading the lifters actually causes premature wear of the internals. If you have to overtighten them, they are worn....replace them and use additives to prevent future losses.
    I only strongly defend this statement due to the fact that we aren't allowed to post the findings from the met lab. All I am permitted to say is that overtightening the lifters (however miniscule) does cause the internals to expire quicker than adequate torque. This amount doesn't immediately show, but will shorten the lifespan.
    Granted, you should still see a good couple thousand hours of use from any good quality lifter. But, we have seen quite a few only live half the life due to excessive pressure. Spending this much time analyzing metalurgical stresses can sometimes make you a bit paranoid about what goes on inside your engine.
    Sorry about the lengthy commentary.
    Last edited by lildino383; 09-08-2010 at 02:06 AM.

  7. #7

    Default

    i am 100% with u !!!!

    1996 Suburban K3500 SLT DUALLY
    1988 Camaro RS 383 stroker LT1
    1992 32' Aero-tek Race Boat, 600 CI BBC
    WE CAN STICK A DIESEL IN ANYTHING
    SPECIALIZED IN CUSTOM CONVERSIONS OF ANY KIND
    Scott:glasses:

Similar Threads

  1. turns but will not start
    By Jeremy.kayla in forum GM Powertrain
    Replies: 5
    Last: 07-19-2010, 11:05 PM
  2. intermittent shudder during right turns?
    By heftylefty58 in forum Chevy Tahoe Forum (GMC Yukon, Cadillac Escalade)
    Replies: 7
    Last: 05-18-2009, 09:28 AM
  3. As GMTC Turns
    By ChevyFan in forum The Coffee Shop ~ Chit Chat
    Replies: 47
    Last: 11-02-2008, 10:43 PM
  4. Dam left turns
    By Fatty89 in forum Chevy Silverado Forum (GMC Sierra)
    Replies: 14
    Last: 05-02-2007, 08:20 PM
  5. engine turns over, but won't start [Expired Topic]
    By whitestonian in forum Chevy Suburban Forum (GMC Yukon XL)
    Replies: 6
    Last: 11-25-2006, 03:05 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •