92 EVO 1340 Clatter

Discussion in 'Engine, Fuel and Exhaust' started by todsho, Apr 16, 2013.

  1. todsho

    todsho Member

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    Hey all..

    I have a 92 1340 EVO. Got it out for the first time this year and rode to work.
    On the way to work I heard a tick and figured lifters needed to pump up after sitting all winter. On the way home, noise got louder..more like a "slap". Its coming from the front cylinder. I readjusted the pushrods and the noise is still there. Its quiet when its cold and gets worse as engine gets warm. Cant hear it at idle..starts at around 2500 to 3000 RPM. I thought it was piston slap but does it only when warmed up and not at idle. Does anyone have any other ideas on what this could be before I tear the cylinder off? This all started pretty quickly...oil press is good and tappet screen is clean..just don't know what else it could be...Thanx
     
  2. Breeze3at

    Breeze3at Well-Known Member

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    Do to the extreme angle, the front exhaust lifter is prone to beat the bearings out of the roller. It happened to my '92 at aprox. 20 K miles. If yours has the original lifters, it's worth checking all of your lifters.
     
    Last edited: Apr 16, 2013
  3. todsho

    todsho Member

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    I thought about that..so I used a mechanics stethoscope and probed the lifter blocks and it is pretty quiet down there...seems to be higher on the cylinder/head. I would think It would be pretty noisy at the lifter block if a lifter was letting go...am I wrong? I very well could be!
     
  4. Jack Klarich

    Jack Klarich Expert Member

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    You have checked for exhaust leaks? Is it possible 1 push rod is rubbing inside the tube? Have you run a compression -leak down test to rule out a valve problem?
    Broken valve guide or spring could be the culprit here
     
    Last edited: Apr 16, 2013
  5. todsho

    todsho Member

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    No exhaust leaks that I can find...I checked the tubs and the front one was rubbing a little so I reamed it out to solve that and noise is still there..did not do leak down yet..I think that would be a next good move along with compression test..the bike still runs well but that noise to me is not normal!
     
  6. todsho

    todsho Member

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    Would excessive carbon on the piston be a possibility? being that it happens when hot?
     
  7. tourbox

    tourbox Senior Member

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    When you re adjusted the push rods was the engine Stone Cold. It needs to be Stone Cold. Another trick is to ck. push rod adj. after the noise starts, when hot. If a lifter is bleeding down when warm you will notice 1 or more push rods looser than when you adj. them cold.
    Did you ck. your oil level? After sitting the carb. could have drained down into the cases and then diluting the oil after running. That will usually cause excess oil in the oil tank. Lots of things to look at after sitting up for the winter and being 20+ years old. Keep us posted.
    tourbox
     
  8. todsho

    todsho Member

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    Thanx for the info Turbobox...I'll try that adjustment procedure and check the other things also...the oil level looked fine but I will check again...
     
  9. Jack Klarich

    Jack Klarich Expert Member

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    This could be detonation from carbon build up, pull the plugs and look for worn electrode, run some sea foam thru it with some high grade gas:D
     
  10. todsho

    todsho Member

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    Ok..I think i figured it out..the pickup plate came loose and the timing was almost all the way advanced..heavy duty gas knock...DUH!..retarded the timing back to where it was and noise is much quieter...exept for a small lifter tick..now have to get timing dialed nack in...
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