Hard to Start Stihl FS 36 Trimmer?

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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?
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On Sat, 01 May 2010 12:28:57 -0700, W. eWatson wrote:

Have the carb rebuilt.
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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.
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Don Phillipson
Carlsbad Springs
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On Sat, 01 May 2010 12:28:57 -0700, "W. eWatson"

Change the spark plug and try again.
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Pull the spark plug out, and yank it a couple times with the plug out. Might easily be flooded.
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Christopher A. Young
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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.
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On 5/1/2010 2:00 PM, ransley wrote:

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 about 8".
Cranking it without the plug isn't dangerous is it?
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On Sat, 01 May 2010 15:55:03 -0700, "W. eWatson"
Not in my lifetime.
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On 5/1/2010 4:30 PM, Oren wrote:

I wish you a long life. :-)
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On 5/1/2010 5:20 PM, W. eWatson wrote:

Pulled the plug. Gave it a few yanks on the cord. Tried again. No start. Monday I'll take it to the saw shop, and tomorrow likely rent one for a few hours.
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On Sat, 01 May 2010 18:28:42 -0700, "W. eWatson"

Like I mention:
_Change the spark plug and try again._
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On 5/1/2010 7:29 PM, Oren wrote:

Still doesn't work. Well, tomorrow it goes to the saw shop for inspection.
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On Sun, 02 May 2010 13:24:50 -0700, "W. eWatson"

Please report back what the shop finds out.
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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.
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On Mon, 03 May 2010 10:13:38 -0700, "W. eWatson"

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.
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On 5/3/2010 10:48 AM, Jeff The Drunk wrote:

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.
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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. MLD
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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.
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W. eWatson wrote:

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 engines operate.
TDD
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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.
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Christopher A. Young
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