Spark plug gets gas fouled every cold start

This is optional. Leave it OFF so you can adjust the carb if needed. The black plastic cap goes over this screw to limit adjustment travel.
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good news is snappers up an running w/ new head gasket an new carb.bad news is she won't turn off w/ ignition key switch.I can't remember if that wire I disconnected at coil is the after effect? IIRC I'll have to ground that disconnected coil wire to turn her off?
here's all what I did the torque wrench was useless at 6LBs also w/12LBs even the 3rd pass I never felt it click, once I think on 12LB I felt a tiny give but not click so I did each pass by feel 18isn't that much even w/ a 18" lenght. but torqued in correct sequence.
note my cylinder head had an extra bolt I counted it as #9 just under #8.
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when I installed the new cylinder head gasket the piston was at TDC I still get confused on which TDC so I took a crape shot an adjusted valves. I couldn't find my complete set of feeler gauges. I did have the .005 so I adjust both valves to .005.IIRC I did that same adjustment last year.
if I adjusted valves on wronge stroke could this be why I hear this loud clacking noise. or could the valve be to tight?

she basically cranked right up this video was basically the 2nd startup. I didn't install new valve cover gasket BC I thought I'd have to readjust the valves I also didn't want the fuel mixed oil on the new paper gasket. even at .005 the gauge was in there tight.I believe this engine has .004 on one valve an .006 on other the ytuber darrel recommends .005 on both not sure about that. I should also mention I don't have an exhaust gasket.

not sure what that loud clacking noise is. when I reassembled the air box w/ new filter the heat shield wasn't tucked in under itheat shield not tucked in.jpg. I maybe hear some exhaust noise. hope I didn't hurt her to bad? thanks Guys I'll report back after fist mow.
sgkent the cylinder is horizontal and the blown gasket was on the top section thats why she shot fuel straight up like a skirt gun.

edit: I reused a preiously gas fouled spark plug and didn't check its gap. that will be fine later. how will I know if the fuel to air mixture is acceptable?

 
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5 days ago she was cranking up an running fine that clanking sound must have been the heat shield bc it went away after tucking it in.
today I mowed the back mowed half then cut the fuel so she would turn off while I emptied the bagger.
when attempting to restart turned her over a few times then on 3rd try she backfired now she won't start up.
I removed the spark plug an it wasn't gas fouled.still swapped a previously gas fouled in no start. I hope that backfire wasn't my new head gasket blowing out?
maybe the valves are adjusted to tight? wouldn't that be unlikely bc she was running so good 5 days ago even restarting several times about 3 times.
any suggestions is appreciated. dam just when I thought I did something back to square one.
I will test for spark an report back.
 
That sheet metal shield directs COOLING air around the block and cooling fins. Put it back where it belongs. Helps cool the engine.

Actually you need to remove it and clean all around the block, muffler and other fin areas. With that shield on, grass and other trash can get inside and clog the cooling fins.
 
In that video you made, sounds exactly like the choke is on. Then you killed the fuel. Telling me the needle and seat is not sealing. Dumping too much fuel trying to run then when you kill the fuel she leans down and runs proper till she runs out of juice.

Did you pressure test the carb needle/seat? Needs to hold 7psi for 30+ minutes. You don't just pull out your credit card, buy a new carb and demand she works proper.
 
Pull the oil dip stick. Smell for fuel AGAIN. If you smell gas, carb needle/seat is NOT sealing proper. Need to fix this before running it any further. Gas will dilute the oil. These are air and oil cooled engines. See where this is going? Don't care if this is a new carb either. New does NOT mean new these days. You MUST test every old and new part you think is suspect.
 
OK I clean all around engine. I believe when I push the throttle all the way forward thats the choke so after ignition I pull back throttle to near the middle where the rabbit is or a tad less. 5 days ago I restarted several times I think I just left the throttle at the rabbit (fast setting). now I have 18 days to return the carb. what do you think that back fire was maybe too much fuel in cylinder? thanks slo mow for fast response.

I let her sit for around 15minutes I thought maybe I flooded her still no crankup. if theres too much fuel in cylinder why didn't the spark plug gas foul again?
no I didn't preasure test the needle an seat I don't have a pump. I know very little about carbs, I basicely just bolted it on I was kindof luckie w/ the throttle,choke and spring going back on easiely.
 
update on snapper: today I charged the battery which was at 11.9VDC charged for 25 minutes then put on recondition for additional 20 minutes. throttle to choke an she cranked right up. finisied the back yard w/ the bagger. I still had leftover leaves from winter. anyway she seams to be running good.
I still haven't retorqued the head after now 2 heat cycles should let head cool down before retorqueing or torque when she's still hot? thanks slomo
 
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