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Any Mechanics here?

  1. Oct 9, 2011 #1
    I have a 94 3000gt vr4 that I haven't driven for about a year. Every week when my office shredding guy comes by he asks about the car, but I haven't really had the need to sell it. Anyway, I finally just figured, hey, I'm not using it, why not let him have it. Mind you, it has sat in my driveway for a year without being started. I told him the tires should be replaced because there is obvious rot, but otherwise the car was in good shape.

    I changed all the fluids, got some oil in the cylinders and turned it over with a wrench a bit, cleaned the brakes and so on. Then I changed the battery out from my other car and started it up. Problem is, there is a ticking sound, that I believe to be the lifters. I was just curious what course of action I should take to alleviate this problem before I sell it? Should I let it run a bit and see if it works it's way out or what?

    Thanks,
    QC
     
    Last edited: Oct 9, 2011
  2. jcsd
  3. Oct 9, 2011 #2

    Danger

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    My first suggestion is to just toss in a can of STP and see what happens. That will usually sort out a sticky lifter.

    While I agree that the problem is probably a lifter, it might also just be your heat-riser valve cycling. If so, there's nothing wrong.

    I should point out that I have absolutely no idea of what car you are referring to. Those numbers mean nothing to me.
     
  4. Oct 9, 2011 #3

    S_Happens

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    How long did you run it?

    Danger, it's a Mitsubishi twin turbo V6.
     
  5. Oct 9, 2011 #4
    I'll look into that, thanks.

    It's a 94 3000gt vr4. It was sold as a Dodge Stealth in the USA as a captive import as well. It's basically a twin turbo DOHC V6 if that helps at all. Everything seems to be in order except for that darn tick coming distinctly from the valve cover.

    I let it idle for about an hour already, perhaps a bit less while I was checking everything else out.
     
  6. Oct 9, 2011 #5
    I found this youtube video. It's a naturally aspirated version of a different year, but the tick is identical.

    https://www.youtube.com/watch?v=VE4oY4CngXc
     
  7. Oct 9, 2011 #6

    Danger

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    Jeez... unless someone tweaked the volume on the video, that's pretty damned loud for a sticky lifter.
    The heat-riser idea is ruled out due to both the location and fact that your engine is injected. Given how loud it is, however, it might possibly be a different component of the valve train than just a lifter. It would be worth the price of a new gasket to pop the cover and check on the health of your rockers.
     
  8. Oct 9, 2011 #7

    rhody

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    I agree with Danger, some STP or something call Top Oil, it may need valve guide seals as well, on old cars infrequently used they dry out and let oil by. Does the engine produce blue smoke when you rev it ? So twin turbo, one turbo for each bank of three cylinders then ? If the top of the engine is easily accessible, then redoing the top end may not be too bad, or just deduct a fair price from the selling price to fix it and be done with it. Get two or three quotes from competent shops and average the repair price. When you said you changed the fluids I hope you meant you changed the turbo oil to right ?

    Rhody...
     
  9. Oct 9, 2011 #8

    Danger

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    Hey now... I just thought of something else.
    A leaking exhaust manifold can make that same sort of sound, and is significantly louder than a lifter. It might appear that the sound is coming from the valve cover when it's just below it.
     
  10. Oct 9, 2011 #9
    I actually had the turbos out of the car while it was sitting because I know they like to seize up, they are in, connected to clean oil, and working just fine.

    I did a bunch of internet searching and it appears pre-99 models of this car are notorious for benign lifter tapping. There are hundreds of videos and sound clips of the exact same thing that this car is doing. The fix that is prescribed is to replace the lifters with the ones from a 99 that have a larger hole for oil.

    I don't want to do any work to the head, I simply don't have time to do it myself and shops charge insane amounts for what is simple work. You don't even need to disrupt the timing to swap out the lifters on this car. I was just looking for some quick ideas to make it quiet down so that I can at least explain the problem to another person who has no knowledge of cars.

    I'll give the ATF additive a shot when I get the chance.
     
  11. Oct 9, 2011 #10

    Danger

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    :confused:
     
  12. Oct 10, 2011 #11
    I looked into using a different oil than the OEM. Many sources have told me that a quart of ATF can clear up clogged lifters, I guess because of the detergent, followed by an oil change.

    Seem reasonable? It's widely known that the lifter clogs in this model.

    Here are the old lash adjusters/lifters vs the new ones.
    lash-adjusters-newer-6-400.jpg
     
    Last edited: Oct 10, 2011
  13. Oct 10, 2011 #12

    Danger

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    :bugeye:

    I must have been hibernating way too long. Those don't even vaguely resemble any lifter that I've ever seen in my life.
    I've never heard of using ATF in that capacity, but I suppose that it might work. Don't do it unless you're scheduled for an oil change anyhow, though; otherwise, you'll just be wasting the good stuff. Definitely don't do any serious commuting with it in there. The advantage to purpose-designed fluids such as STP is that they are non-intrusive as to their lingering effect. Just fire-and-forget, with no need to flush them out.
     
  14. Oct 10, 2011 #13

    FlexGunship

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    I have the same engine (3.0L DOHC) in my Eclipse but it's a non-turbo. Had the same problem. If it's not a lifter, it could be the auto-tensioner for the timing belt (that's what it was for me... it was so loud that I rejected the idea for weeks before replacing it), if that's not it, then it's the deadly crankwalk!!!!!!

    Crankwalk: http://www.google.com/search?source....,cf.osb&fp=ebaa3ff8b466872e&biw=1215&bih=750
     
  15. Oct 10, 2011 #14
    God I hope it's not a timing issue/crankwalk. I had an older Mitsubishi Evo that chewed up it's own valves due to the dumb idea of intrusive engines.

    I don't plan to drive with the ATF in, and yeah I'll change out the oil anyway.

    I guess I'll give that a shot and see if it makes any difference at all. It's been sitting a while, if I crack it open I am afraid of what I might find! :yuck:

    I think I could verify whether or not it's a a valve or something by turning it over with a wrench and listening to it?
     
  16. Oct 10, 2011 #15

    Danger

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    So nothing named "Evo" is mechanically inclined, even if it's a car... :biggrin:

    I wouldn't count on that. Most such things are rpm-dependent, at least to some degree.
     
  17. Oct 10, 2011 #16
    I would be willing to bet that by letting it sit for a year, the oil pump has drained back and lost its prime. Your issue is that you're not getting enough oil pressure to the heads. There may be a procedure to re-prime the oil pump.... However, just running the engine will eventually let the oil pressure build up again. Some engines take upwards of an hour to do this (It is risky to do this method though)....

    Note: Don't run the engine if the oil pressure light is on, on the dashboard. That's a bigger oil pressure issue.

    Another note: if your hydrolic lash adjuster (what you have in the picture) was clogged, you would not hear the noise you are hearing. In fact, with proper oil pressure, it would be pressing the cam roller against the cam lobe with substantial force (because it would want to rocket out of it's hole in the cylinder head). Instead what you have is an inadequate adjustment of the valve lash that can only be attributed to not enough oil pressure. Which means the cam lobes are whacking the cam rollers on the rocker arms.

    Personally I would advise against the oil additive unless you are taking the valve covers off and applying it directly to the cam lobes, lifters, rocker arms, etc; (which wouldn't take care of the noise, but it would reduce the wear as the pressure built back up). Otherwise you are simply making the oil thicker and harder to suck up the oil sump and pump through the small oil passages.... After the air has passed out of the system, sure, but not before.
     
    Last edited: Oct 10, 2011
  18. Oct 10, 2011 #17
    Thanks for the reply. When I started it up I let it idle for an hour and it did not seem to quite down any. I do know that the clogged lash adjusters cause lifter tick in this model fairly rampantly. A quick google search for "<pre-99> 3000gt lifter tick" will show you exactly how rampant it is. I'm not saying that you are wrong, but I would not want to overlook the most common fault attributed to this year of the car and it's specific lash adjuster.

    I'm looking into re-priming the oil pump. Seems as easy as disconnecting the cam angle sensor and cranking it, but that is only from one source.

    Any other suggestions are welcome.
     
  19. Oct 10, 2011 #18
    Here you go!... I know it says 1996 models, but I got this TSB after specifically entering your year into the mitchell on demand.

    VALVE NOISE AT START UP - V6 & DOHC

    Reference Number(s): TSB-95-11-001
    Related Ref Number(s): TSB-95-11-001

    ARTICLE BEGINNING

    VALVE NOISE AT START-UP


    Model(s): 1996 Mitsubishi Models with V6 and DOHC engines

    Reference: Engine

    Bulletin No.: TSB-95-001

    Date: November 1995

    BACKGROUND INFORMATION

    On V6 and DOHC models, it is normal to hear a valve noise (a "ticking" sound) during the first two minutes after engine start-up. However, vehicles that are overdue for oil change or have not been started for a long period of time may experience the noise for longer than two minutes. The noise is caused by air in the high pressure chamber inside the automatic valve lash adjusters.

    Replacing valve lash adjusters will probably not eliminate valve noise. This bulletin contains procedures to bleed air out of the adjusters and to confirm that the adjusters do not require replacement.

    VEHICLES AFFECTED

    All V6 and DOHC models

    PROCEDURE
    If valve noise (a Ticking sound) lasts more than two minutes after engine start up, perform the following steps in order.

    1. Check the engine oil level and quality, and correct as necessary. Start the engine. If the valve noise continues for longer than two minutes after start-up, continue to step 2.
    2. Warm the engine to normal operating temperature. Increase idle speed gradually to 3,000 RPM, then back down to normal idle speed. Repeat this process several times (maximum of ten times). If the noise continues, stop the engine. Inspect the automatic valve lash adjusters as described in Steps 3 and 4 below.
    3. Remove the oil cap on the rocker cover and listen for the source of the noise. If it seems to be coming from the valve lash adjusters, proceed to Step 4. Otherwise, refer to section 11 of the appropriate service manual for further engine diagnosis to deturmine the cause of the noise.
    4. Remove the rocker cover.
    5. Using finger pressure, push down on the rocker arm over the head of each valve lash adjuster. See Fig. 1 and Fig. 2
      NOTE: Be sure that the camshaft lobe is on the flat side when performing this step.
      1. If the head of the adjuster sinks when finger pressure is applied, the adjuster must be replaced.
      2. If the head of the adjuster stays firm when finger pressure is applied, the adjuster is operating normally. Do not replace the adjuster. Refer to section 11 of the appropriate service manual for further engine diagnosis to determine the cause of the noise.

    Fig. 1
    Fig1.gif

    Fig. 2
    Fig2.gif
     
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