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Hello everyone.I am a first time poster here,looking for some advice.

I recently bought a old push mower with a Briggs 625ex engine. The engine will not crank,even when priming the carb with carb/choke cleaner or starting fluid.
I removed the carburetor to give it a good cleaning.
With the carburetor off,I sprayed a small shot of starting fluid into the intake to see if it would fire up a second. It did not.
The firing at the spark plug looked as good or maybe even better than anything I've ever seen on one of these engines.
What's left besides it maybe being out of time? I thought I would ask here before I tear into it to check the camshaft.
I'll add one more thing to this...........The blade control/brake cable is broken. Since I don't know the history of this mower,I don't want to go buy the cable until AFTER I get the engine running.So for the time being,I removed the brake cable spring so I could release the brake and keep it from grounding out the ignition. Obviously,I will buy a new cable once I get the engine to crank.
I have next to nothing invested is this mower so it wouldn't be an issue if I have to buy a few parts for it.The old mower looks good except for some scratches here or there.It looks like it was garage kept for sure.

I would be removing the flywheel to check the key long before I would remove the engine to check the camshaft timing. That can only get out of time two ways and both are idiot caused. But hitting something with the blade will shear the flywheel key and will still fire the spark plug just not at the right time.

Thank you for the reply, ILENGINE. I didn't think about the flywheel key because,other than being dull as a fro,the blade looks free of any gouges,damage,etc.
As I'm sure you can tell from my post,I'm just a novice but I've always been able to keep my vehicles,mowers,saws,etc,going myself,even before the internet,lol.
You've learned me something today,though. I thought if the flywheel key was sheared,the engine would not be firing at all. With that statement alone,I've learned something today.
Is removing the flywheel the only 100% sure way to determine if the key is sheared?
Thanks again for your advice!

jeff902 said:

Thank you for the reply, ILENGINE. I didn't think about the flywheel key because,other than being dull as a fro,the blade looks free of any gouges,damage,etc.
As I'm sure you can tell from my post,I'm just a novice but I've always been able to keep my vehicles,mowers,saws,etc,going myself,even before the internet,lol.
You've learned me something today,though. I thought if the flywheel key was sheared,the engine would not be firing at all. With that statement alone,I've learned something today.
Is removing the flywheel the only 100% sure way to determine if the key is sheared?
Thanks again for your advice!

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If you remove the nut/bolt and the starter cup you should be able to see the keyway slot and see if the key is straight or offset, or completely out of alignment. the older point system engines wouldn't fire if the key was sheared but the electronic ignition doesn't depend on timing to fire.

ILENGINE said:

If you remove the nut/bolt and the starter cup you should be able to see the keyway slot and see if the key is straight or offset, or completely out of alignment. the older point system engines wouldn't fire if the key was sheared but the electronic ignition doesn't depend on timing to fire.

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I'll take the cover off today and take a look. Just in case I do need to remove the flywheel,I'll have to go buy a puller.I rarely use a gear puller and just as I expected,mine is missing in action.
Thanks Again for replying back to me.

remove the spark plug and spin the engine a few times noticing the feel. Put the plug back in and pull it again to notice compression. If you have compression spray a little starting fluid in the plug hole, put the plug in and the wire on, see if it fires. You could have a situation where the cam lobe is wiped out (no fuel/air gets into engine) or the valves need adjustment (no compression).

sgkent said:

remove the spark plug and spin the engine a few times noticing the feel. Put the plug back in and pull it again to notice compression. If you have compression spray a little starting fluid in the plug hole, put the plug in and the wire on, see if it fires. You could have a situation where the cam lobe is wiped out (no fuel/air gets into engine) or the valves need adjustment (no compression).

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sgkent, I have already done what you've described. it might spit or sputter but not truly start.​

As far as compression,it feels to me it has plenty,maybe too much.Maybe the compression relief not working?It doesn't grab the rope out of my hand or anything that severe.It just feels to have a lot of compression.As I stated earlier,I am just a novice that tinkers with stuff on a common sense level.I don't pretend to be a mechanic but I usually can finish what I start,lol.
I don't know if this website will let me post a pic since I'm new here but I will attempt to load one now

Key looks fine. make sure to properly torque the nut back down. Will need actual model number from engine cover to get you the correct torque spec.

ILENGINE, Yeah I was hoping it was going to be this simple. Oh well,it was certainly worth checking. Thank You!​

I'll now go and see if I can find correct torque for the nut.
Model 093J02-0006-F1

did you check the oil for fuel in it? Too much fuel or too little fuel will both make it spit and sputter. So will a plugged exhaust if it sat outside and mud daubers filled it with mud. So will a bad or fouled spark plug.

sgkent, thanks for replying back.
I didn't see or smell any signs of fuel in it.I can always check again.
The old mower no doubt sat in a garage or shop,etc. The red paint and plastic is too bright to have ever been weathered much.
You bring up a very good point concerning the muffler. It was probably 20 years ago maybe longer. I had a 2 year old weedeater that wouldn't start after sitting for the winter. I was stumped trying to figure out why it wouldn't start. It had fire and fuel but would not even try to start. I had ran out of things to check.
As a last resort,I checked the muffler for blockage. Bingo...........those mud daubers you mentioned had the muffler packed tight. Once cleaned,it fired right up.

I'm pretty sure the old push mower won't be that simple.
I might just open the bottom of the engine tomorrow to see what that plastic camshaft looks like.

I bought this mower just a few days ago for 15 bucks. The owner said it ran last year but wouldn't start this year. I'm thinking it would possibly be carb trouble,magneto,or something simple. For 15 bucks,what do I have to lose,ya know.

Something just occurred to me as I'm typing this reply.It hit me like a ton of bricks,so to speak.
Whenever I brought the mower home,I took the engine cover off to just to see if there were any mouse nests or anything that had accumulated over the winter.
What I did find was a chewed up black plastic ring wedged beside the flywheel. After pulling it out,it was pretty easy to assume it was some to type of cover that originally snapped around the starter rewind.
If that piece wedged in there while the engine was running,that may be the culprit that started this trouble.
Sorry for the long post