Help, No Spark
#1
Help, No Spark
Ok its a 12.5 hp briggs verticle shaft engine. I was told it ran fine when I got it so I was trying to get it to run last week and no spark. I replaced the coil with a brand new one and still no spark. The little wire from the coil isnt touching ground either. I have it bolted down about as close to the flywheel as I can get it without touching. The magnent will pick up my screw driver so I know its strong. Im getting very aggravated with it, does anyone know what else could cause this??? Could the starter not be spinning it fast enough? I would really like to hear anyones thoughts on this, I really need to get this running.
Thanks alot for everyones help.
Thanks alot for everyones help.
#2
Join Date: Apr 2004
Location: Upstate New York
Posts: 2,903
Upvotes: 0
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The starter certainly must have enough power to get it to spin at least 350 rpm but 500 is better. A typical electric starter in good condition will spin about 7-800 rpm and a typical pull starter will spin at about 4-500 rpm. Does yours have pull-start option? If not and you aren't sure if the E-start is spinning fast enough, try using a jumper battery. If you believe it is, in fact, spinning well enough, you need to pull the kill wire off - AT THE COIL, and then check for spark. This eliminates the possibility of a bare spot in the ground (kill) wire and thereby grounding out. And be sure to set the coil to magnet clearance at .010".
#3
The kill wire is off and will try to check rpm tomarrow. I dont have a pull start, wish I did. Also is setting the coil .010 that important? On my 3.5hp I just put it close and have no problems.
#4
If you don't have feeler guages to set the gap, just use a business card. It's close enough to work well. Are you sure the coil isn't on upside down?
#5
Originally Posted by cheese
If you don't have feeler guages to set the gap, just use a business card. It's close enough to work well. Are you sure the coil isn't on upside down?
#6
I got spark today, the new coil gave me a few but when I put the old coil back on it, it sparked like a beast. When I put the plug back in the engine it had compression and the starter didnt have enough power to spin it, I guess its time for a new starter. I put two 50 amp bettery chargers on the starter to really spin it.
#7
Originally Posted by michaeljp86
I put two 50 amp bettery chargers on the starter to really spin it.
#8
I will try that tomarrow, I had 100 amps though but I should giv it a stab before buying a new starter like I did the coil. Thanks for everyones help so far, hopefully I get it going tomarrow.
#10
without the spark plug probably 300, It had a good spark. The new coil had a very small spark and only every once in a while. With the spark plug in it spins fine till the compression stroke then it stops, doesnt have enough power to run it past. I have a battery on the charger so Ill try it with the battery later and see how that goes.
#11
Well today I stole the battery out of the lawn mower and charged it for a while. With this very old battery and the 100 amps of the chargers It spun it good. Finaly I got it to fire on starting fluid an I rigged up a pop botle fuel tank and it ran good in the 30 degrees. Thanks for everyones help Im glad Its going, now I can get on with my life.