I've had Subject trimmer for ten years, and of late it has been hard to
start. I've probably yanked on the cord about 80 times this morning, and
a few times it sputters and dies. I've had it in choke and run
positions. Usually run gets it going. The outside temp is 62F. The
little transparent fuel clear bulb has lots of fuel in it, as required.
There is a bubble in it that may be 1/2" in diameter. I used it the
other day for 30 minutes.
How to proceed?
This normally happens when carburettor components
(diaphragms or springs) are sufficiently worn that they
no longer meet system specifications. The OP did not
say whether his carburettor was ever serviced in 10 years.
Miniature carbs like this do not last for ever.
When my 36 got hard to start the carb was fouled from storing gas in
it and I had to get it cleaned. Pull the plug after trying and I bet
its wet and flooded, so use dont flood it if possible. Either-
starting fluid should help but the final solution might be a carb
cleaning, a new plug might help, when the plug is out ground it and
pull the cord to see if the spark is good.
I suspect it is wet, but I can't find my spark plug wrench. I think it
looks like a socket wrench with a lever arm protruding from the side
Cranking it without the plug isn't dangerous is it?
I took it in this morning, and the "silent" mechanic gave it a shot. In
about two minutes he had it running. I asked him what he did. Two pushes
on the rubber ball to prime it, and set it to Choke. I think it took him
about 10-12 pulls to get it to life. I said I often start with Run. He
said again use Choke.
I got home and did exactly what he did. Nothing after about 15 pulls, so
I switched to Run and with about 8 pulls it was running.
I think my problem is that after I've about gotten to 15-20 strokes, I
prime about 5-6 times, according to the number in the book. I may be
flooding it. I guess that's detected by the pull getting jerky.
30 minutes latter I had chopped down 3' dense weeds in my wife's 20x20
garden, and knocked off about 15 minutes worth of other scattered weeds
around the property. Mission accomplished.
Push the prime ball ONLY until it feels stiff. Often you won't have to
push it at all if you use it once a week. When you push the primer it
shoots gas into the carb venturi and you will flood the cylinder if
you push it several times. From your description I would push the
primer twice, set to choke and pull. When you hear it fire for a
couple strokes reduce the choke amount and pull again. At this point
it should run for a few seconds or more. If it stays running let it
run for 15 seconds then reduce the choke while running to half.
If that doesn't seem to work then reduce the choke a bit before you
attempt to start it. Most small engine choke butterflies have a small
hole in them as to not over choke.Make sure yours is clean as it's
real easy to everchoke a small engine that has no flywheel.
Your trimmer should not take 10 or more pulls to start. None of my
small engine tools like saws, blowers or trimmers take more than
three. Most only one. My Lawnboy 6 horsepower 2 stroke engine sat all
winter with gas in it. I pressed the primer 4 times fast, set the
choke and it started on the first pull. Mowers and blowers have an
advantage of having a pseudo flywheel in a blade or blower impeller.
Small trimmer motors around 30cc have to be in good shape since they
have no momentum without ignition.
Reduce the choke? As far as I can tell, there are two settings, Run and
Choke. This may not be true though. My impression has been the two
positions have a lock feel to them. So what you say above may solve this
problem. I may need to use it tomorrow, so I'll check it out. In fact,
regardless of the need I'll experiment as you indicate. It's use is
mostly confined to the spring when I have to deal with a lot of weeds.
We have 7 acres, and certain areas require the trimmer. Most of the
grass and weeds I'm concerned with are in a 1/3 acre area. The rest is
dealt with differently.
I was having a heck of a time getting mine started--spoke to an "old codger"
at manufacturer's Tech support. Recommendation was to push the prime bulb
about 14 times (vs. 7 for manual) according to him it would not flood the
engine as the excess fuel just goes around in some sort of loop. Then I
noticed that the fuel supply tube in in the gas tank was pointing down and
at times could actually be out of the fuel while I was pulling away. I
rotated the machine such that the tube was always immersed in fuel when
starting and that made a major difference in getting it running. Minimal
starting problem since I made that adjustment. Also, after too many pulls
and no start, the tech guy said put it in the Run position.
Taking out the plug and just pulling it a few times does and proves
nothing. Was the plug wet indicating flooding? Did you attemp to check
for spark. Starting fluid would be something easy to do that might
make it go. Its only dangerout taking out the plug and pulling the
cord when you stick you foot inside the cilinder.
You can test the ignition system of a 2 cycle trimmer by using
compressed air. Put the rubber tip of a blow gun or spark plug
adapter attached to an air compressor tank and the engine will
run on 50psi air. You pressurize it and pull the starter rope
to get it started and it will putt merrily along. You can see
if you get a good spark from the detached plug wire while the
motor spins. It's no mystery if you understand how 2 cycle
Just pull the spark plug wire away from the hole, and tuck
it behind something (or tape it to the side of the machine).
Yanking without the spark plug will help dry out the
cylinder, which is probably flooded. Might restart, then,
after the spark plug is put back in.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.