# small engine repair - lawn mower



## tngbmt (May 30, 2004)

i wanted to learn a more beneficial hobby .. so taking up small engine repair

i bought a b&S 675ex troy bilt mower from craigs that was not running. key start, front drive. initial attempt to start, locked up pull string, didnt even turn. i manually rotated the blade and it turns but did not fire.

taking it apart .. testing spark plug, have fire. put a new one in anyway
put new gas, new oil, carb examination .. have gas in the bowl
there was pressure at the spark plug 
took the fly wheel off to examine the key .. it's good
tried the spoon of gas in the spark plug .. not even a sputter
re-checked the gap of plug, fly wheel mag contack

she turns but doesnot fire .. 
any suggestions?
tia


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## reeltimer (Feb 5, 2010)

could be the coil.

Sent from my SGH-T989 using Tapatalk 2


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## speckle-catcher (May 20, 2004)

if the flywheel has a magneto - check the spacing. If it's no far, it will not spark

last riding mower I had, I think the space was about .020 - or use a business card if you don't have a feeler gauge


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## carrerajason (Oct 7, 2009)

ok.....4 things actually make the motor run......fuel....air ....spark....compression. You checked fire...no problem? compression? fuel? That was always my first test. spray somne starter fluid in carb. Now see if it run.....and dies. If it does......the carb bowl hasd a bolt in it on the bottom. That bolt actually has a hole it it...as it is used to suck gas into the carb. they get clogged quick. Bliow it out...and bingo. Also on newer mowers where yoyu have to have the handle pyulled in for the machine to run.....make sure that isnt grounding out anything. sometimes it miss adjusted.


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## BullyARed (Jun 19, 2010)

You had a spark before taking off the flywheel. Since you took the flywheel off, you must re-align the timing (firing mark on the flywheel). This is the position where the piston is at its highest point for combustion and the spark (ignition) occurs.


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## jz2518 (Nov 29, 2012)

i recently made my john deere propane. i was having carb trouble. and i read that propane is better to the engines. You could try that . you can find lots of tips on youtube.


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## peckerwood (Jun 9, 2012)

Never,ever turn a blade without pulling the plug wire off or plug out.If it fired,you can loose both hands.Not being a jerk,just makes me feel better bringing it up.A guy I work with has only a thumb on his right hand from doing that.If it's an older mower,buy a electronic ignition kit and convert it over.Takes all the gapping and guessing out and doesn't cost maybe 20 bucks.That's just a guess.


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## WRsteveX (Sep 6, 2012)

If its got spark, compression, air.. It's got to be fuel. Fuel in the bowl means nothing. There are several small air and fuel passages in the carburetor that need to be clear. Small engines-small carbs- small passages. Doesn't take much to clog one. 

Why was it not running? A little backstory goes a long way. Was it running when they parked it? Died while mowing? Slowly lost power?


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