Briggs Micro .75HP Engine

Discussion in 'Homeowner Assistance Forum' started by WorkinOnIt, Jun 8, 2012.

  1. WorkinOnIt

    WorkinOnIt LawnSite Member
    Posts: 46

    Briggs 021032-0112E1-0405182A 34cc 4-Stroke "L-Head" engine. Has new head gasket, new coil, new gasket and diaphragm kit in Walbro Rotary carb, valves ground to .007" and .010" stem to tappet clearance. Compression 60psi bone-dry. 90-100psi with few drops oil. Engine ran 1 week ago but would not idle. It died and wont start since. Fuel introduced into spark plug hole OR carb intake immediately gets blown out through the crankcase breather tube when pull-starting. The breather tube connects to the end of the camshaft (which is hollow and made of nylon). This engine has an aluminum block. The air gap on the magneto is set at .010". Does anyone know why there is a no-start condition? The repair manual states the compression should be 50-60psi. I know Briggs doesn't normally list their compression ratings for their larger engines. Is the intake valve not seating properly? Thanks for any help!
     
  2. WorkinOnIt

    WorkinOnIt LawnSite Member
    Posts: 46

    I feel I may have been mistaken as the "backpressure" pushes out of the intake manifold thru the carb . The mistake was made because the breather tube is mounted right next to carb intake on the air filter mount. Lots of puffing, but no start.
     
  3. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,240

    The usual suspect on these engines is the plastic cam...the teeth on the gear break or strip...if its off 1 tooth it won't run..
    Posted via Mobile Device
     
  4. WorkinOnIt

    WorkinOnIt LawnSite Member
    Posts: 46

    The nylon breather assembly holds the end of the cam in place. I have seen it (of course). While viewing it, I didn't notice any damage. Can I do a re-inspection and attempt to retime the thing? I have rotated the engine with the breather cover off and the cam moves erratically with nothing to stabilize the end. The camshaft is hollow (nylon I think) and the breather hose to the air filter plate connects on to it. So I have compression, valves are better now...but the timing may be off (even one tooth). Can I fool with it and get it back in time?
     
  5. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,240

    First....you posted in the homeowner assistance forum...if you had posted in mechanics and repair ...you would get more support...
    Its been awhile since I had one apart...
    I believe there is a side cover that when removed you can see the side of the gear....
    Rotate the gear slowly and inspect the teeth..
    Posted via Mobile Device
     
  6. WorkinOnIt

    WorkinOnIt LawnSite Member
    Posts: 46

    Yes, I posted there because there was a post when i signed up that stated people who were homeowners and not business owners were to post there. If I would have done it MY way, I would have posted in the mechanics and repair...and WILL from now on, because that is what I do. That being said/........The cover is off. There is a timing mark on the cam gear of the camshaft. Rotating the engine thru its motions shows NO stripped gears or missing teeth. There is a nylon drive gear for the cam on the crank, but I see no indicator mark. Where do you suppose I align the timing mark of the cam gear to?? Again, the nylon crank gear and the nylon cam gear seem fine. What do you suppose the timing mark on the cam is reference to?
     
  7. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,240

    I haven't seen 1 of those engines in over 5 years...
    Go ahead and start a new thread in the mechanics forum.
    Somebody will have the answers you need...
    Posted via Mobile Device
     
  8. WorkinOnIt

    WorkinOnIt LawnSite Member
    Posts: 46

    Thanks Piston Slapper.
     

Share This Page