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mvron

Bolens 110 25CC string trimmer wont start

mvron
10 years ago

I have acquired this string trimmer. It looks very new. It will not start. I tried starter fluid - with no success. I have a spark tester that I connected to the spark plug - looks like no spark. Ideas on what to try next. thanks for any ideas.

Comments (14)

  • loger_gw
    10 years ago

    Try grounding the plug the old fashion way by grounding it to metal of the cylinder with the plug out and pulling for spark in the start mode. I read that some low dollar spark testers âÂÂas mine", less than 10.00 do not last long. A good grounded plug has never failed to show spark. If there is truly no spark, itâÂÂs time to do some testing. Search for a youtube on the matter or go with basic testing with a multimeter.

    I recently had no spark with a kill switch connected in the On or Off position and fire w/o the switch.

    Who is this trimmer maid by?

    Good Luck!

  • mvron
    Original Author
    10 years ago

    I believe that Bolens was purchased by Ryobi but now has returned to MTD.

  • mvron
    Original Author
    10 years ago

    It appears after looking at the spark plug and the string spool that the trimmer had run a little at one time. It apears that the engine does have compression. Even if someone ran the unit with straight gas, it should have spark. The engine does not appeared to be seized. Haven't - can't look into the engine to see if the cylinders are scored. The on/off switch is spring loaded to the on position. The unit looks almost new - really strange that it dosen't run. I tried testing spark against the engine - no spark. Not sure if the engine is plastic or metal.

  • loger_gw
    10 years ago

    1. Did you try a different plug?
    2. Can you easily disconnect the kill switch?
    3. Test what you grounder the plug against with a magnet that will attach to metal.
    4. Good hot sparks are not easy to see in the daylight (test in a dark area).
    5. Is this a 2 or 4 cycle Eng? Remove the muffler to see in the cylinder if it is a 2 cycle.

    Give It Heck!

  • mvron
    Original Author
    10 years ago

    1. yes
    2. No, I have to take the handle apart-but I might do that.
    3. Find a magnet
    5. It's a 2 cycle

  • mvron
    Original Author
    10 years ago

    I found a magnet. There is nothing on the engine housing that is metal - all plastic. Found another piece of metal and no plug spark. I want to check the compression on the engine also. Can't find my compression tester so I will have to find another one. Then I'll take apart the "on/off" switch and check that out.

  • loger_gw
    10 years ago

    1. Where the plug screws into the cyl should ground and give you a chance to see a spark.

    2. A basic small engine compression test is you can not hold the compression in with your thumb.

  • mvron
    Original Author
    10 years ago

    I'm not sure I know how to check the air gap between the flywheel and the magneto - what should I be looking for? The compression test shows about 42. I don't think the spark plug will reach the engine block - but I'll try again. I want to be sure that no spark is the problem before proceeding. Thanks for ideas.

  • homegrown55
    10 years ago

    See if a standard business card will SLIDE between the LEGS of the ignition coil and the magnets in the flywheel.The card is approx. .010". The coil can be adjusted with the mounting screws that hold it To set it, loosen the coil screws, slide the card in front of the legs and turn the flywheel until the magnets PULL the legs against the card. At that point, just tighten up the screws and it is set, but definitely check it. If your compression is 42psi, the engine probably won't start. That is VERY low compression.

  • loger_gw
    10 years ago

    1. I doubt the 42 psi compression is correct. If it is, the cylinder is probably bad. If it is 2-cycle, you might want to pull the muffler âÂÂNEXTâ look into the cyl for shiny cyl vs a scored/scratched one. If the cyl is bad the compression will bad. The End!!

    2. If the cyl is not bad, a better screw in gauge should give 75-100 psi on 3-4 strokes.

    3. The hole where you rem the plug, touch good as a ground testing for spark.

    4. If you see a spark wet your plug in 2-cucle fuel, install plug and try for fire.

    5. Spark, fuel and compression is needed to run. Try .5 tsp of fuel in the carb full throttle.

    6. If it fires but w/n continue to run, ck all fuel lines, cln carb internally if needed.

    Good Luck!

  • mvron
    Original Author
    10 years ago

    It is a 2 cycle engine. I tried several more compression tests with about the same results with my old tester. I don't have a threaded tester. Do you know of anyone that would use/rent for 1 minute? I will take the mufler off - it's behind a major large cage structure - and check the cyclinder bore. Maybe get a threaded compression tester on Ebay, use it and then resell later. I don't want to spend more on the trimmer than it's worth. Thanks for the ideas.

  • mvron
    Original Author
    10 years ago

    I got the muffler off with the help of my jig saw - don't ask. I could see the cyl bore and the piston. Both looked really scored and scratched. My guess is that because the unit looks new - very little usage - that someone ran straight gas through the trimmer - instead of the 40-1 mixture. Again thanks to all for the numerous ideas. As you say, this is the "end of the story".

  • homegrown55
    10 years ago

    There were springs; not screws on your muffler i take it? Sometimes a "stuck" piston ring will cause the compression loss, and causes abnormal cylinder wear before it quits.

    This post was edited by homegrown55 on Wed, Jul 31, 13 at 19:20