On 15 May 2007 13:08:31 -0700, wrote:

On May 15, 3:29 pm, "jacko" wrote:
If your spark plug is wet then fuel starvation is not the problem . Have you
tried a new plug. The old one may be breaking down. In any case it sounds to
me like loss of spark for whatever wrote in message

ups.com...

Hi all...
Hoping that someone could point me in the right direction.

My parents' Toro gas lawnmower doesn't want to operate.... it will
start running but dies within a second.
I checked the float in the carb and it works just fine, the needle
valve is not stuck and the reservoir has plenty of gas in it.
The engine will only start if I prime it about 5 or so times, if I try
to start the motor without priming it - it won't budge.
I tried different plugs to no avail. However, I noticed that once the
motor starts and dies, the plug is wet, which tells me that the mixure
is too rich.

Couple of questions at this point:
- what does the prime button do? Does it only fill up the float
chamber with gas? Or does it also pump some gas into the engine for
quicker starts?
- do lawnmower carbs have an adjustment somewhere where I can reduce
the amount of gas sucked into the combustion chamber?

Any help would be greatly appreciated.
Alex

Hey guys... thanks for the replies.

I tried two brand new spark plugs with same effect. Checked for spark
- she's there too.
I thought about trying to do it without the gas cap but it was too
late as I was already on the way home.
I can understand the clogged cap but how would that explain the wet
plug though?

Did you gap the plug correctly? A minor change in the gap can make a
difference.

Plugs can vary. One might burn hotter than another. The right plug and
gap are important.

The power stroke is not burning the fuel.

(A bad valve/seat?)


In any case, anything is worth trying and I'll get at it next weekend.
I'll even swap out carbs with a spare one I have here to see if that
is causing the problem.

I should have mentioned that the gas in there is over 6 months old
(was not stabilized over the winter), but my parents are telling me
that it ran ok two weeks ago on the same gas.
--
Oren

"The voices in my head may not be real, but they have some good ideas!"