Valve issues on a 4 stroke

Discussion in 'Instructions for Building and Repairing Motorized ' started by Ryan Haddock, Oct 23, 2017.

  1. Ryan Haddock

    Ryan Haddock New Member

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    So new to the forum.... Decided to adjust my valves thought all would go well .. Big mistake... Can't get it running right tried several times several adjustments. 33cc 4 stroke Chinese kit..... Any help please
     
  2. MEASURE TWICE

    MEASURE TWICE Active Member

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    I expect others here may know more than me on this and should respond. I have had Briggs engine 4 stroke where I had to adjust the valves as they had worn into the seats and stayed open too long which looses compression. Adjustment on this old type means grinding off the tip of the valve stem. But for the newer engine you have, did you have some printed instructions on the method for valve adjustment? I guess you have the OHV with adjustment for rocker, I have a small generator like this but have not adjusted it. Temperature may be an issue when doing the adjustment. I think they have the adjustment when cold, but not sure. Using a feeler gauge that is not squished or distorted I feel is important. On another note my engine is hard starting after it warms up. I have heard that the engine when stopped and the fan on flywheel stops cooling the engine, the valves can get still hotter for a while. Sometimes I have to wait 1/2hr to get it to restart. I did check the valves, but did not want to take the head off and do this process as the engine ran well. I was swapping this newer used engine in at the time. Now that I found that it could not restart when hot, I will be doing the adjustment now.
     
  3. Ryan Haddock

    Ryan Haddock New Member

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    Yeah I think maybe I bent something or whatever cuz it just won't quit cutting out at any adjustment. Think this Chinese ohv job is just too cheap for even adjustments . hurt my feelings but a learning experience for sure hope my new flying horse is worth the money
     
  4. MEASURE TWICE

    MEASURE TWICE Active Member

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    https://motorbicycling.com/forums/motorized-bicycle-trouble-shooting.34/

    It might be possible that something else just happened to go bad at the time you adjusted the valves and the valve are adjusted just fine. Above some area for troubleshooting.

    Basics are Fuel, Compression, Ignition. And yes timing for both valves and spark, but the 3 are really key.

    There is a post that became as sticky thread but don't know where it is, some one should direct you to it. It goes step by step for everything about engine trouble shooting. Of course 2 and 4 stroke are different to some degree, this thing seemed to cover what was sound advise.
     
  5. MEASURE TWICE

    MEASURE TWICE Active Member

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  6. Ryan Haddock

    Ryan Haddock New Member

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    Thank u
     

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