Re: Motor runs rough at low rpm and idle
My first thought was the same as what you said and then i thought if there was a crack in one of the cylinder walls, you would have a compression leak and you would not have the same compression in both cylinders. 90psi is a little low. Perfect compression for that motor is 110-120psi. Make sure when you do a compression test that you remove both spark plugs at the same time so there is no compression on one cylinder while your testing the other. There is a product out called ceramizer that restores compression(you can google it to learn more). Your spark is good but you might want to try a hotter plug to see if that helps. Ok last test = For starters allow water to pump through the engine while doing this. If you do not have electric start, you can use an electric drill with an adapter for using sockets. Take out both spark plugs and have a container so you can catch the fuel from both cylinders in it. Turn the motor over( if you use a drill with a socket attachment, get the right socket that you need and you can turn the motor over by putting the drill and socket on the flywheel nut and using the drill to turn the flywheel. While doing this catch as much fuel from both cylinders as possible(remember to have ears on your motor or your motor in a barrel of water while doing all this)and pour the fuel in a see through container. Let it sit for an hour and then see if you have water in the fuel. This will tell you if you are getting water in your cylinders. Good luck
