I have a mower with a Tecumseh LV148AE / LV195EA engine that will run pretty well once it warms-up, but getting it started when cold is quite a challenge.
The way I have been able to get it started is to keep pulling on it about 20 times. At that point, I might get it to fire once or twice. Another 10 pulls and it'll fire again maybe five or eight times. Finally, it'll start running.
Stopping the mower for a few minutes to empty the grass, it'll start up with one or two swift pulls. Even if it's been off for an hour, it will startup after a few swift pulls. But if it sits since the last time the grass was mowed, it needs that huge number of pulls to get running.
My theory is that it's not getting good compression any more. I've ruled out fuel and spark as a problems since it runs pretty much flawlessly once it's warmed-up.
My plan is to do a bit of diagnostics the next time I need to run the mower. I'll start by doing the 10 pulls, and I expect no firing. Then I'll remove the spark plug, put some oil in the cylinder, and replace the spark plug. If it immediately starts, then I'm going to presume that's because the abundant amount of oil is causing a better seal between the piston rings and the cylinder wall, giving me better compression.
Is the above diagnostic idea a valid one?
EDIT:
Squirting oil in the cylinder did not make much difference. My next attempt is a new plug. The existing plug looks good and is properly gapped, but I'll try the plug next (simple things first).
Another idea is if the muffler is causing too much back-pressure, so if the plug doesn't help, I'll take the muffler off for another quick test.
EDIT: Additions based on comments
- The mower has a bulb to press, and I've used it as directed.
- I have tried starting fluid, but it doesn't have much impact, which is why I was thinking it wasn't a fuel issue.
- I can get an entire new carburetor, delivered, for $10, which I will try after I replace the plug.
- Smoke is not a symptom, so that aligns with the oil in cylinder test not having improvement.
- When I say "cold" I mean North Carolina spring cold, as in 50F. The winter might have gotten down to 20F, though.
- There is no manually operable choke mechanism.
- I do not see a fuel filter in the parts diagram.
Last EDIT:
- Replaced the carburetor (see my answer, below)
Best Answer
I had an identical problem as yours with my Toro 4-cycle mower. Eventually, the mower wouldn't start at all, which I tracked down to a dead ignition module (ignitor). After I replaced it, it's been easily starting for about 4 or 5 years now. The ignitor looks like this:
This may or may not be your problem, but if you've eliminated everything else...
I used a piece of card stock to set the gap between the ignitor and the rotor.