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Briggs and Stratton 18 hp problems

Discussion in 'Mechanic and Repair' started by csdog08, Sep 17, 2007.

  1. csdog08

    csdog08 LawnSite Member
    Messages: 3

    I am hoping to get a bit of advice on an engine that is in a riding mower I own. We moved to a new house about 2 years ago and this has set for the past two years as I have completely rebuilt the house we bought. We are in the country and with the dry summers this past couple of years, mowing has not been a serious issue. My neighbor wanted to play with it and see if he could get it running. We got rid of all gas, changed out the fuel line, charged batteries, cleaned starter switch, and it finally turned over and tried to start. We pulled the air cleaner and fired a bit of starter fluid into the carb. She fired right up and then stalled. After several times we got it to fire up and stay running but it really needed to be choked. The air cleaner was still off. We also noticed that there was a fine mist of what is gas blowing out the top of the carb. The engine does not back fire. If I keep it choked at about 3/4 it actually runs fairly well. I do not have compression testing gauges but when turning the flywheel by hand, you can turn it for about 3/4 and then it is next to impossible to turn. My neighbor has a bit of training and said this is a sign of good compression. We were wondering if the blow of mist coming from the top of the carb could be a valve problem. He is telling me the carb is very clean to look at it from the top. I am getting a feel for what we can do or if being a cheap mower it is time to say enough and buy another one.


    Mod 42A707
    Type 2238EI
    Code 0103215A

    Thanks for any help you can offer. I am not really up on mechanical stuff. Want a house built, I can do it. Engines are not my thing. Rick
  2. Restrorob

    Restrorob LawnSite Fanatic
    Messages: 11,029

    Well Rick,
    If you take the carb off and dismantle it, Clean it very well with carb & choke spray cleaner with the little straw spraying through ALL ports and passages. Install a FULL rebuild kit that includes the fuel pump diaphragms this will eliminate the need to run the unit at 3/4 choke and the mist will most likely stop.

    Good Luck
  3. Bill Kapaun

    Bill Kapaun LawnSite Senior Member
    Messages: 949

    You can download an IPL at the link. It'll have an "exploded view" of the carb, so we can use the same terminology.

    Does this carb have the electric fuel solenoid? If so, make sure it "clicks" when the ignition is turned on.
    Most likely, the Main Jet (ref 117) is clogged.
    IF cleaning that doesn't fix the problem, continue with the rest-
    A fuel pump kit (ref 861) MIGHT be in order. A ruptured diaphragm may be causing the spray/lack of fuel.
    The carb probably should be disassembled and cleaned, but you might get by without doing that.
    Also examine ALL vacuum/fuel lines for air leaks.
    A new fuel filter is also a VERY good idea.
  4. csdog08

    csdog08 LawnSite Member
    Messages: 3

    Thanks for the input. I may consider haveing it done by someone else so I can't make any problems. I will have to take a look. Glad to hear you don't think it is valves. Rick
  5. csdog08

    csdog08 LawnSite Member
    Messages: 3

    Thanks a bunch for the reply. First, I have downloaded and printed the IPL. Second, I will have to check on the solenoid. I do know the neighbor told me there are no adjustments for the carb like on other motors he has worked with. I will go over in the next day or two and compare the list to the actual carb. The fuel line has been replaced. I will check it over. I am starting to think just rebuilding would be a good idea. I will see what I find. Rick
  6. topsites

    topsites LawnSite Fanatic
    Messages: 21,653

    Stuck bowl float I'd be willing to bet.

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