Need Help with 6 year old Toro 6.75 HP Push Mower ... Issue Starting

Discussion in 'Homeowner Assistance Forum' started by Tim_in_NC, Apr 11, 2008.

  1. Tim_in_NC

    Tim_in_NC LawnSite Member
    Messages: 6

    Hi everyone,

    I ran across this site while searching the web for potential things to try while troubleshooting my push mower.

    It's a 6.75 hp Toro self-propelled/push mower ...

    I've been having a tough time getting it the start over the past several months. It normally takes priming the carb (via a push bulb) 10 to 15 times and then pulling the cord another 15 or so times until it will finally start and some times it starts and then immediately dies but then the next pull or two it starts and continues to run ...

    I've replaced the plug, replace the air filter (no fuel filter on this model), and I've completely dismantled the carb - soaked and cleaned to like new condition.

    Immediately after I thoroughly cleaned the carb and reinstalled, the mower fired right up on the 1st pull (all the carb cleaner surely helped it fire up) and I let it run for about 30 minutes. But then the very next time I used the mower, it's gone back to taking forever to fire up ...

    I don't notice any fuel leaks, but I'm thinking that I'm just not getting enough fuel to fire ... maybe the push bulb on the carb is gone bad, but it doesn't appear to have any cracks or leaks ...

    Any help would be appreciated.

  2. LarryF

    LarryF LawnSite Bronze Member
    Messages: 1,181

    Well Tim, there is another forum called "Mechanic and Repair" here at LawnSite, and that would be a better place to post this question. But I suspect it might be moved there anyway.

    You didn't say what kind of engine, which might help, and you didn't say whether you were closing the choke. I presume you were, but sometimes after a few pulls with the choke closed, the engine gets flooded and opening it a bit helps. I think you should be able to tell when you are pushing the primer button if you are pumping fuel. At the first couple of pushes when there is only air in the bulb, there will be little or no resistance, but when doing that some more you should be able to feel the increased pressure as the bulb fills up with fuel. If you do feel that increased pressure, it seems to me that the primer is doing what it is supposed to. Of course, you can also take the plug out after several pumps and pulls to see if it's wet with fuel.

    If it is getting gas, then week spark should be looked into. You should be able to check that by taking the plug out, reconnecting it to the spark-plug lead, grounding the plug against the engine, and pulling the starter cord. You should see a strong spark.
  3. Tim_in_NC

    Tim_in_NC LawnSite Member
    Messages: 6

    Thanks Larry ...

    I didn't post in that section because it states that it's only for Lawn and landscape business owners. This was the only section that I saw for Non Business Owners ...

    Thanks for the tips ... I'll work at it further and report back ...

  4. LarryF

    LarryF LawnSite Bronze Member
    Messages: 1,181

    OK, but I had interpreted that statement to mean lawn owners and landscape-business owners. But I don't think those who manage this website would mind if homeowners (a.k.a lawn owners) like you and me ask and attempt to answer questions on it.
  5. mouse

    mouse LawnSite Member
    Messages: 98

    If the engine ran after you cleaned the carb but went back to hard starting the next time you tried to start it then I would make sure the fuel tank and the line to the carb was clean and in good shape I.E. line not hard and or brittle flaking off on the inside thus plugging the carb up. Also always use a fuel stabilizer.
  6. IA_James

    IA_James LawnSite Silver Member
    from Iowa
    Messages: 2,592

    Have you looked at the primer bulb real close? If you have a crack in it the thing will suck air through it and not want to run.
  7. Valk

    Valk LawnSite Silver Member
    Messages: 2,723

    If that's a Briggs 6.75hp OHV engine that was considered an upgrade (over the standard Briggs 6.5hp engine) back in the day, then they inherently came with starting the point that one of my local Toro dealers wouldn't even sell that model to anyone.

    I had two of these (yeah, didn't learn the first time :hammerhead:) and both cold started fine, but if I was to shut it down in the middle of cutting a yard for too long (more than a few minutes) then I was in for a workout getting that thing restarted. Nothing was ever resolved...

    I chose these engines because they were considered an upgrade that burned cleaner and used less gas. Not sure if they burned cleaner of not, but they certainly got less mileage than the standard Briggs 6.5hp.

Share This Page