Help! Mower won't start

[gocards1177]

Yep. Sheared. Ill check the points next. Will be headed to parts store for pin, points and condenser. I may try reassembling with just the pin first.

 

[RandyT]

It just takes the flywheel key to be off a few thousands to prevent spark when the engine has points.

To the guy asking about points in small engines. Briggs used points on all there engines until 1980.

 

[gocards1177]

It just takes the flywheel key to be off a few thousands to prevent spark when the engine has points.

To the guy asking about points in small engines. Briggs used points on all there engines until 1980.

Shoot! I replaced the shear pin, put it mostly back together, and tried to start it. It fired once and then nothing. So I figured I would go back in and replace the posts and condenser. As I'm doing that I've found the pin sheared again! Now I'm not sure what to think. Maybe I'm on the wrong track.

 

[gocards1177]

One thing I forgot to mention is that during reassembly I notice the retainer that screws down onto the flywheel is stripped. I tightened it some but not nearly as much as required. Could the lack of the hold down pressure simply contributed to the sheared key and I'm still on track with the bad timing?

 

[gocards1177]

Reassembled. One big fire then nothing. Sheared again. I was able to get the retainer threaded and I torqued the bejeezes out of it. Maybe I'm assembling it wrong, but u don't see how.

 

[gocards1177]

After more research (thank you google) I'm thinking the sheared pins is a combination of inadequate torque on the retainer, the stripped threads, and I didn't clean the shaft and flywheel were they mate before assembly. Resting now but will try again this evening. It's muggy in Missouri!

 

[gocards1177]

FIXED on my last flywheel key! It seems that it was the sheared key/bad timing all along. I believe what led to the failure was the stripped threads on the starter clutch that led to the flywheel becoming dislodged from lack of downward pressure.

Unfortunately I couldn't get the starter clutch tightened enough with the Belleville washer in place but I could without it. So I don't know how long my fix will last bit if it goes out again Ill start with a new key and clutch.

I ended up not doing anything with the points and condenser other than verifying the correct gap. As for new tools I ended up with a feeler gauge and flywheel puller that I didn't have before.

Thanks for everyone's help!

 

[jimmysisson]

Next time you replace the key, rub a little blackboard chalk on the taper as you seat the flywheel. Helps it stay in one place. Prolly you're sick of the r and r by now?
Jim

 

[gocards1177]

Next time you replace the key, rub a little blackboard chalk on the taper as you seat the flywheel. Helps it stay in one place. Prolly you're sick of the r and r by now?
Jim

It always seems on days like this I'm cussing myself during the process but when I'm done I have a sense of accomplishment that's worth it.

 

[gocards1177]

More mower problems...

I was mowing around our pond a few days ago and the engine died. It restarted fine (electric start), would now for about ten more feet, then died again. This repeated itself a few times and then when I tried restarting it it would just make one sharp "click" and not turn over. I figured it was a bad starter/solenoid/dead battery so I loaded it up with my FEL into my truck and brought it home.

I was able to look at it this morning and it was still doing the same thing. Battery had 12.7 volts. Took the cover off and the gear on the starter was engaged to the flywheel rather than down in the "relaxed" position. I couldn't turn the flywheel by hand, so I removed the spark plug. Still wouldn't turn. Looked underneath and the pulley on the crankshaft and the belt seem fine - no binding or obstructions. There seemed to be some play between the starter gear and flywheel teeth but I removed the flywheel anyway. The starter activates just fine without the flywheel attached. I put a big vice grip on the crankshaft and I can't get it to budge.

My fear is a seized engine but the way it behaved before ultimately dying doesn't add up. Plus if it was seized or something catastrophic wouldn't the flywheel key have sheared? Could I have done something a few weeks ago during my repair to have lead to this? After that last fix I have mowed 2-3 times and it seemed ok.

 

[RandyT]

I suspect you have a lack of lubrication failure. I am assuming that you were mowing on a slope. If the oil was slightly low, it could of got the oil slinger out of the oil which lead to engine seizure. If the engine doesn't have an immediate seizure, it may not shear the flywheel key. the sudden stop of the crank is what will shear it.

 

[gocards1177]

I suspect you have a lack of lubrication failure. I am assuming that you were mowing on a slope. If the oil was slightly low, it could of got the oil slinger out of the oil which lead to engine seizure. If the engine doesn't have an immediate seizure, it may not shear the flywheel key. the sudden stop of the crank is what will shear it.

Ugh. Not what I wanted to hear. I wouldn't say I was mowing on flat ground, but it wasn't super slopey either.
Well I was planning on someday tearing down and rebuilding the engine, but I was hoping that would be after mowing season.

 

[gocards1177]

Yep. Just drained the oil. Hardly a fourth as much as I would have expected. What a shame. I could have easily prevented this ha I been checking.

 

[gocards1177]

Running again! Disassembled head. Hammered the piston lose. Lubricated the cylinder thoroughly and kept turning the crank with a vise grip until it could be spun by hand. Reassembled and it started!