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Ok now I'm frustrated (more of a vent thread)

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  • Ok now I'm frustrated (more of a vent thread)

    Well I thank all of you who have helped me in my previous thread, which is still on the first page or two.

    I ended up buying some washers from a hardware store and putting the stock rocker arm studs back on my car. I was hoping this would correct the issue I had before, since I did cross-thread the adjustable studs I bought which resulted in the rocker arms coming loose.

    Well after putting the stock studs back on with the Comp 1.6 roller rocker arms and an aftermarket cam (listed in previous thread), I fired up the engine and prayed everything would be good. The engine fired immediately and sounded pretty good. I didn't hear any abnormal noises from the heads, and it sounded like it did before I rebuilt it. I listen for about a minute and all seems good.

    So I started clearing a path in the garage to take my car for a test drive as it warmed up, but after a period of time I did begin to hear a chattering sound. This was all too familiar. Sounded like only one or two rocker arms were coming loose again. I continue to let it idle for about 20 minutes or so. The chattering did get worse, and I started to see an abnormal vibration in the engine that wasn't there when I first started it up. The exhaust also sounded like it was cutting out/missing a cylinder.

    So at this point I'm pissed. I get into the car and tap the accelerator a bit to see what it sounds like when it revs up. It sounded bad, and the chattering sound I heard got louder. However, it didn't seem like all of the rocker arms were loose, just one or two from the front of the engine. I didn't really hear any chattering from the rear valve covers, but of course they are crammed underneath the Intake Manifolds, alternator, firewall, and various sensors.

    I shut the damn car off and head into the house, wondering why the suckers had come loose. I really don't know what to do now. I torqued down my studs to a little over spec, 20 ft-lbs. I torqued down all the rocker arm nuts to the spec in the Haynes manual, 18 ft-lbs. I did use a washer on top of the pivot ball to make up for the 1.6 ratio rocker arms.

    I even zero-lashed a few OEM rocker arms and then noted how many turns it took, and repeated the process with the roller rockers (on the same stud and pushrod). They were pretty much the same, although the roller rocker nuts stopped turning about 1/4 turn less than the stock rocker arm and nuts.

    If anyone has some advice for me, that would be great. I'd really like to know if anyone has used the 1.6 roller rockers with an aftermarket cam, and leaving everything else OEM, in a '92 3.1L engine. Should I just put some lock-tight on the nuts to keep them from backing off?

    Gah I probably don't make much sense right now. Forgive me.

  • #2
    Did you grind the guides to clear the pushrods? You need to do that for the 1.6:1 rockers.
    Ben
    60DegreeV6.com
    WOT-Tech.com

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    • #3
      Yeh I grinded them. There is the possibility that I didn't grind enough off of some.

      Could that be the problem? The thought crossed my mind, but I didn't think the rocker arms would come loose so quick.

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      • #4
        sounds to me like you didnt adjust lash correctly. not trying to be rude, but are you completely positive you adjusted the valve lash correctly, it kind of sounds that you adjusted the lash when some of the valves were not completely closed (cam not on base circle)
        94 Grand Prix
        3400- NX 75 shot, Cammotion cam, S&S headers, and a few more toys

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        • #5
          I did't adjust the lash for each cylinder. The stock nuts just torque down on the stud with the stock rocker arms; they stop at a certain place. You don't have to adjust if you use the stock studs, since they aren't adjustable studs.

          I was told I could use the 1.6 roller rockers with the stock studs. All I needed to do was put a washer between the nut and ball. I did so.

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          • #6
            That should have done it. I don't know why any would loosen up like that.
            Ben
            60DegreeV6.com
            WOT-Tech.com

            Comment


            • #7
              Yeh neither do I.

              I didn't take off the valve covers to confirm how many loosened up, though. I just left the garage in disgust, called my brother and asked if he could come down and look at it since he has more experience with cars than I do.

              This was my first rebuild. It was a great learning experience, but I couldn't count the number of things that went wrong or I screwed up. I was particularly careful when I reinstalled the stock studs and the roller rockers too, because I had to take off the lower intake manifold as it was blocking one nut + stud on each side of the engine. Just one on each side. The other 10 nuts I could access just fine.

              So I reeaaalllly do not want to take the intake manifolds off yet again, although I'm pretty much leaning towards putting the stock rocker arms back on. I'm sure if I put some lock-tight or whatever on the nuts to keep them from backing off I'll be fine, but I have yet to see if performance will be good or not.

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              • #8
                I purchased the 1.6 rockers. At first when I installed them I ended up with this:


                Then after some searching I did this:


                1.5 turns from zero lash IIRC is what I finally decided was the best adjustment.
                Lifting my front wheels, one jack at a time.

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                • #9
                  1.5 turns from zero lash is a lot. ive always run mine at 1/2 turn without issues, in fact, thats what ive run on every hydralic lifter motor ive built. yes it always seemed loose any time i adjusted them, however the lifters were always bled down and you will get movment.

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                  • #10
                    Here is my other thread:


                    1988GTU, looks like you got the adjustable studs, right? In my other post I actually had the ARP adjustable studs on first, but I made a mistake. The tops were 3/8" and I put 10mm nuts and pivot balls on them. The threads on the studs got little damaged but were probably usable (a picture is in my other thread.)

                    Instead of getting new nuts and pivots, I just installed the the stock studs back on and used the stock nuts. I also bought some grade eight hardened washers. I would say there were about the thickness of a dime. Anyway, before I installed them I did zero lash a couple of rocker arms, and it took about 1.25-1.33 turns before the nut torqued all the way down on the stud. I also zero lashed a few of the stock rocker arms, to see how many turns it took, and they took about 1.33 to 1.5 turns for the nut to torque all the way down on the stud.

                    So I figured I was pretty good with the washer and the 1.6 ratio rocker arms, except somehow at least one came loose.

                    Also, waht does IIRC stand for? I've seen it a few times, but I have not seen what it means.
                    Last edited by cusideabelincoln; 08-31-2007, 11:15 PM.

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                    • #11
                      IIRC = If I Recall/Remember Correctly
                      Your local OBDII moderator

                      2000 Grand Am GT w/ WOT parts

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                      • #12
                        Well that's a new one for me.

                        Anyway, another question.

                        What would happen if a valve on a cylinder wasn't opening? If either the exhaust valve or intake valve wasn't opening, wouldn't that cylinder by trying to create a vacuum or compress air? Would this cause the engine to basically stall or die? Would it take more than just 1 valve on more than just 1 cylinder to cause the engine to die?

                        I ask this, because I went back out to the garage to start the engine again, but it only fired for half a second and then died.

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