Possible issue with my 153cc Tecumseh Engine

Discussion in '4-Stroke Engines' started by AnvilBlockForge, Mar 11, 2013.

  1. I'm using a Tecumseh H35 Motor for my motorbike. Despite reviews, I have had no problems with the engine besides regular carb stubbornness. But I have noticed that when I crank it up and try to drive off, if it hasn't warmed up it will die and won't crank till about 10 to 15 minutes of leaving it alone. This happens every time it stalls out for various reasons. Now initially I suspected a carb problem, but it was perfectly fine. What is causing it to not want to crank after dying and how can I fix it?
    Last edited: Mar 11, 2013

  2. BigBlue

    BigBlue Active Member

    Last edited: Mar 11, 2013
  3. darwin

    darwin Well-Known Member

    That carb is a lil more complicated than the standard Chinese carb. If your fuel flow from the tank is ok then it has to be the carb/choke providing theres no air leaks. Heres what your carb should look like. Everything needs to function as it was designed for. Every o-ring to the float/needle seating. Iwould look for a fuel restriction in the carb. What does the plug look like when it won't start or dies? Is it dry or wet? http://www.searspartsdirect.com/par...0040376/00003?blt=06&prst=0&shdMod=H35-45495M
  4. I think you may have posted the wrong link BigBlue, theres only two postes on that post

    And I've just recently replaced the vacuum lines, fuel lines ect due to excessive cracks, and the Bowl seal could use replacing I suppose, but could that be the problem? Bad seals? I would actually love to replace that carb, because the stock has no adjustments other than the idle.
  5. BigBlue

    BigBlue Active Member

    Sorry about that. Don't know what the heck happened. Here's the correct link:

    Here's some info on Tecumseh carbs that might help:

    It is either going to be a fuel or ignition problem, so your going to have to focus on those two items. Saying it doesn't want to crank, you mean it doesn't start or there is no spark? What kind of ignition do you have? Traditional points and condenser or a modern CDI unit?

    AKA: BigBlue
    Last edited: Mar 11, 2013
  6. What the guy in that forum is explaining is exactly what is happening to mine BigBlue, it has a magneto, but it always has a spark. No problems there. It dies, but after a while, it will crank right back up. From there it either runs, or dies, as the guy described. If it dies, I then have to wait a while to try to start it. I need this fixed, I'd enjoy a reliable motor on this bike xD