rod knock or exhaust leak how to tell

Discussion in 'The Powder Keg' started by sawnoffshotgun, Mar 2, 2010.

  1. sawnoffshotgun

    sawnoffshotgun Suspended

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    I am looking at a truck that definently has a bad exhaust but im ok with that since itys just a mudder anyways. Im assuming its gonna have some kind of exhaust leak which sounds a lot like a bad engine bearing but I want to make sure that it is just a bad exhaust and not a bad engine. Does anybody know a good way to tell an exhaust leak apart from a bad bearing?


     
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  2. DWFan

    DWFan G&G Evangelist

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    Put the tip of a long screwdriver against the engine block and the handle to your ear while the motor is running. A bearing knock will be amplified, an exhaust leak won't.
     
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  3. Mooseman684

    Mooseman684 G&G Newbie

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    You can also use insulated Pliers and Pull each plug wire as it is running...Listen to the Knock...If it changes on One Cylinder or disappears , That is a Bad Bearing...A rod Knock will sound more like Metal hammering than an exhaust leak will and will usually be louder...The Stethoscope is also good to use...
     
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  4. FortyXDM

    FortyXDM Super Moderator Staff Member

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    Don't wear a hat or get your hair caught in the fan blade ! :D:D
     
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  5. sawnoffshotgun

    sawnoffshotgun Suspended

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    Thanks for the help guys.
     
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  6. killsnapz

    killsnapz G&G Enthusiast

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    A bad connecting rod will sound exactly like what it is decribed as a knocking sound. A cracked exaust manifold will sound more like a collapsed lifter and will make a loud ticking sound. If you have any type of rapping noise that you can hear better with a long screwdriver pressed agianst the block then you probally should assume you are going to be spending alot of money on the engine.

    Michael
     
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  7. samuel

    samuel G&G Newbie

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    If it is dangerous,get your wife to check it out.If she gets her hair caught it may save money at the beauty shop. ,,,sam.
     
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  8. 338RUM

    338RUM G&G Evangelist

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    when listening to the block of an engine I prefer a wooden broom handle for pre stated reasons... an exhaust leak would be a tick sound (if leaking around the manifolds) and a bent push rod or bearing would leave a much louder knock...
     
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