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Discussion Starter · #1 ·
Hello all, got a 1980 Mirage II with a 377. Previous owner said sled didn't run. Took the motor apart and nothing looked terrible, except the crank seals looked like they were done. Rebuilt the motor with new seals, pistons, condensers, plug wires. Compression is over 100, both sides. Timing is perfect according to timing marks, as well as dial indicator on piston with test light. Good spark with plugs out, gap is .016". Got the primer line full of gas and gave it a squirt (carb bowl is still empty at this point and through this whole ordeal). First pull it fired weakly for a few revs, then nothing. More primer, nothing. Squirt some gas into plug holes, nothing. Plugs come out wet. Will not even fire on starting fluid. Changed plugs, fired once or twice, then nothing. Again, good spark with plugs out and timing is perfect. I know it's harder to make a spark under pressure, could the coils be too weak to fire under compression? My blood pressure is through the roof, any input is welcome.
 

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Your compression has to be 125 min to have an easy starting and good running engine.If you squirt gas and no go ,then has to be compression or ignition problem.Be sure your condenser has been soldered correctly ,wire not touching condenser body itself. Did you use resin free solder ? DOnt think both coils would go bad at same time.Did you check ring gap and piston clearance before closing it ?
 

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Discussion Starter · #3 ·
Condenser installation should be okay, (I'm an electronics tech) and spark looks good. With new pistons, clearance and ring gap were within specs and cylinders were honed, but compression should be better than 100. Could they be out of round? I guess I'll pull the cylinders, there should be some rub marks in the fresh crosshatch by now, I'll look for uniform contact.
 
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