**HELP** Engine has spark but won't start

#1
Hello everyone. I have this vintage Briggs and Stratton 3hp engine that I am restoring. I replaced the old breaker points ignition coil, to the modern electronic magneto coil. After I did that, it started right up and ran perfectly. From there, I removed the carb and gas tank, so I could repaint the engine. I reassembled everything and when I attempted to start it, it would not go. I sprayed starter fluid into the intake, and it would fire slightly, but did not come close to running. I am not sure what the problem could be. I cleaned the carb out. I Have a good spark plug, and new gas. I also replaced the flywheel key, as I misplaced the original one. The oil appears to be clean. I also feel compression. I have attached some pictures of the gaskets, as I think that may be part of the problem, but I have no idea at this point. I could really use some help.
 

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#3
be honest with you, those gaskets don't look good, but should in theory be able to get the engine to run, albeit not real well. if it were me, i would go through and check the flywheel key, and the coil to see if installed correct. got spark? try a shot of ester? i think if you removed the coil you flipped it putting it back on. just some ideas for you.
food for thought........ old teacher of mine once said, "if you need to know what's wrong or how to fix a vehicle,
always look at the service history. it has to do with what the last person did." he's been right quite a few times.
 
#4
A good seal, gaskets, are key to the cab working correctly. If there is an air leak, anywhere, it will disrupt the vacuum needed to pull the fuel out of the tank. Buy two new carb to tank gaskets and use both of them. Then make sure your vacuum pump is sealed. It never hurts to buy a new diaphram and a gasket.
 
#5
A good seal, gaskets, are key to the cab working correctly. If there is an air leak, anywhere, it will disrupt the vacuum needed to pull the fuel out of the tank. Buy two new carb to tank gaskets and use both of them. Then make sure your vacuum pump is sealed. It never hurts to buy a new diaphram and a gasket.[/QUOTE

There is no diaphram on this carb. The OP has provided a photo of an engine with a "Vacu-Jet" carb that do not use diaphrams.
Michael
 
#7
#8
https://www.small-engine-projects.com/briggs-tank-mounted-carb-repair.htm

"All tank-mounted carburetors use a diaphragm to pull gas from the gas tank. Some diaphragm covers are held on with slotted screws. The diaphragm cover on my Briggs 3.5hp motor was held on by four small Torx screws. A Torx bit socket (T15) is needed to remove these. "
wrong. vacu jet carbs do not,and again,do not use a diaphragm. please do not confuse pulsa jets with vacujets.
depending on where the air leaks are will depend on how the engine will or can run. the gasket in the second picture wont effect the pull of fuel from the fuel tank. the first one can.
 
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