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Want to rebuild Suzuki late 80's DT 40

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  • Want to rebuild Suzuki late 80's DT 40

    Easy engine to rebuild? Engine runs but has low compression. What is the chance it will only need rings? If needing pistons is it good to go .25 or .50?

  • #2
    I believe it would be easy for you !


    • #3
      May want to check with your local machine shops to make sure they can machine your engine if it needs it. Some automotive machine shops won't do marine engines for not having the correct fixtures. I ran into that situation with motorcycle engines myself.
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      • #4
        If low compression readings are caused by carbon-stuck piston rings then maybe research and try a decarbonize process using certain fuel chemicals/additives. What are your compression readings?.....false readings could lead an individual to consider a rebuild which could be un-needed....


        • #5
          It's outside in the cold right now. When it gets above 32 F I will pressure wash it an bring it in for compression test. A jet unit was on it and they are hard on cylinders/rings. We shall see. I know some get away with just rehoning the cylinders and new rings, in fact I have done it before. Wondering if that might be possible on this engine.


          • #6
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            IT has compression about 95 in each cylinder...think that is enough? The guy who sold it to me said he thought it had bad compression, it's winter, so I can't start it to see if it runs or how it runs. If this is enough compression, maybe it was just a dirty carb or some such.