No start honda HR194 with gxv120

[38racing]

Mower dropped at our dumpster. Usual first test of trying it on injection of carb cleaner. No go. Inline tester shows some spark but with just plug out and grounded I didn't see spark. Tried a new plug and again in line shows spark and a one point but grounding plug out gave spark but still no fire. The odd putt but nothing consistent. I decided to check compression. 50 PSI. I pulled valve cover. Intake was ok at .006 but exhaust was .012. I adjusted back to .008. Also I noted the compression release bump on the exhaust. Rechecked compression and lol it was down to 50. That makes sense of course as I had the compression release now opening further. I was about to pull the head when I was called to supper. After supper I went to google and found a youtube on testing compression on these engines. Guy showed a perfectly good engine displaying 50 psi because of the release. Then he moved exhaust rocker off the valve and removed the push rod. Now he had well over 100. I tried the same thing and I'm at 160. So the head stayed on. I went back to spark issue. Inline tester sparks as I crank but no fire. so I decided to check the flywheel key. It was fine. I did remove flywheel so I sanded rust off the coil legs and magnet. I adjusted coil to spec of .016 but I did it at magnet ( Honda says to do it away from magnet). If I ground inline tester from lead I can get spark just by moving flywheel by hand. But if I spin it with cordless drill with a spark plug out and grounded to engine I get no spark (maybe odd flicker once IIRC). I have the kill wire off so I concluding that I have a bad coil.

[bgsengine]

first try setting air gap to .012 (from magnets) and see if that bit of gap makes any difference? possibly a weak magnet... and test with kill wire off. also, unscrew the resistor cap from plug wire and re-test (jury rig a way to attach plug wire to tester or plug) - could be a broken plug wire or bad resistor cap. (plug boot)

[38racing]

Unscrew cap as per being threaded on?

[bgsengine]

typically yes. unless it is some aftermarket coil with permanently attached boot, every Honda i have come across has a threaded on resistor cap boot..

[38racing]

So I readjusted the gap. With plug clamped I get inconsistent spark. I can see that it misses some. I removed the
the cap. I get 4200 ohms on it and 12000 ohms on the lead. I set lead close to cylinder head and spark is still inconsistent. Some times wide orange , sometimes narrower blue/white. I can hold it off and move closer until I get spark. Always close to 1/8 inch to get spark. So I then put plug in and if I put lead toward plug end I get blue/white jumping about 1/4 inch. I think I have just enough lead length to put a right angle metal end on it to fit plug and will see what I get at plug gap.

[38racing]

So I added the lead end and holding it 1/4 inch from installed plug I got good spark. I removed plug and clamped to head. Good spark. So I tried a squirt of carb cleaner and it fired a bit. So I installed the shroud and added gas to the tank. If I choked it it would start but just putt putt and not come up to speed. Off choke it would stop. Also when putt putting there was occasional backfire from carb. So I pulled shroud again and reset gap at .016 away from magnet. I used cordless drill now and it would start and putt putt. Spraying carb cleaner in did not seem to help but carb backfire seemed to be gone. After a couple of restarts it's putt putt suddenly changes to proper running like a switch had been thrown. I did a few short runs. Early ones closing choke while running slightly increased rpm. Last few it may have slowed slightly but did not choke it enough to stop. I tried to engage blade but unfortunately I discovered that it's not disengaged. Maybe cable is seized. Other problem is this mower is designed for a bag and neither bag nor frame were with it.

[38racing]

I just found service manual. It gives valve clearance of 4 and 6, not the 6 and 8 I found elsewhere. It gives the compression test procedure that I found on YouTube. My thought is that maybe compression release was stuck on giving the putt putt and when it righted itself is when engine ran right.