Briggs Carb Question

Discussion in 'Mechanic and Repair' started by matthew horner, Apr 5, 2007.

  1. matthew horner

    matthew horner LawnSite Senior Member
    Posts: 696

    I inhereted a john deere sabre with a briggs inteck motor. The mower had been left out, with the air filter off the carb, so it was full of water, acorns, and a years woth of trash. I took it off and cleaned it up really well, and I replaced the float and needle valve, fuel filter, air filter etc.

    Well, when I crank it, it just "puffs". One puff per stroke, high pitched. And this is with starter fluid. It is firing, but not really firing, or going on its own.

    Would I be better off just grabbing a new carb?

    Thanks,
    matthew
     
  2. Restrorob

    Restrorob LawnSite Fanatic
    Posts: 11,024

    You should be able to have it start and run for a few seconds on the starting fluid until it burns it up. I use carb. & choke cleaner for this because it doesn't dissipate as quickly. It sounds like possibly valves not seating (surface rust) or possibly dried out carbon broke loose and got under a valve. I believe I would do a little more checking before spending 60/70 bux on a carb.
     
  3. matthew horner

    matthew horner LawnSite Senior Member
    Posts: 696

    Thanks restro. You wouldn't happen to have any literature available for posting on the valves on this motor would you> its an inteck.
    Thanks,
    M
     
  4. Bill Kapaun

    Bill Kapaun LawnSite Senior Member
    Posts: 910

    If it's an OHV engine, you can easily remove the valve cover and check to make sure the valves are moving, instead of being stuck open.

    PS did "etc." include the spark plug?
    With the carb being "open", rain could enter the carb, run into the cylinder (rusting things up) and eventually into the crankcase, especially if the intake valve happened to be open.
     
  5. matthew horner

    matthew horner LawnSite Senior Member
    Posts: 696

    Bill, thanks,
    yeah, I want to check those valves, and am trying to find the best way.

    By the way, its a vanguard, not an Inteck. So, i'll just need to get to those valves. Yeah, there was water in the crankcase. I had do drain and flush everything etc.

    M
     
  6. Bill Kapaun

    Bill Kapaun LawnSite Senior Member
    Posts: 910

    Matthew,
    Thinking about it a bit more-
    Either valve could be in a rusted open position. When you remove the valve cover, look for an excessively loose push rod. Also make sure the valves move. You may need some penetrating oil on the stems to free them up, IF stuck.
     
  7. Restrorob

    Restrorob LawnSite Fanatic
    Posts: 11,024

    Hey Matt, Did you get my last PM ?
     
  8. matthew horner

    matthew horner LawnSite Senior Member
    Posts: 696

    Restro, sure did, I'm getting it all together to take it out to the shop.

    Thanks for the help my friend.
    Matthew
     
  9. matthew horner

    matthew horner LawnSite Senior Member
    Posts: 696

    Bill and Rob.
    I took the valve cover off, and turned the motor. Both valves are moving, but there is also a point at which both valves appear to be not so tight (as in I can move the rocker). What can I do from here, to further diagnose/fix this, before I go to the trouble of removing the head? Can I take the rockers off and move the valves around in the hopes of freeing any carbon/rust?

    Thanks,
    Matthew

    PS-Bill, I got the kawasaki going. I adjusted the choke a bit, and it sure helped. Thanks a bunch for that.
     
  10. Restrorob

    Restrorob LawnSite Fanatic
    Posts: 11,024

    If you look at the valve adjustment procedure that is in the top dead center area and is somewhat the area needed for adjustment.

    I really don't know what you can do on the outside in way of seeing/checking the valve seat area for rust/carbon without a leak-down tester and even doing that test could lead to the head removal anyway.

    I would just go ahead and pull the head, Follow the instructions I sent and you shouldn't have any problems. If so all you have to do is shout !
     

Share This Page