Lawn Mower

Can't get it started. Was working a month ago.
Briggs & Stratton 3.5 HP Oil is good Air filter good Replaced spark plug cleaned wire
Two adjustments I played with but don't know what they are? Allan key .. and flat head screw driver adjustments.
Can't get it started ... what do I try?
Thanks
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Maybe the key. Briggs uses an aluminum key where the blade fits onto the shaft. Take the blade off and examine the key. If the key is bent even slightly, it'll never start.
Bob
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
NO WAY .... what is that all about .. how do they cut off the engine if a key way down there is bent?

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

That's a built in safety mechanism so you don't beak your crankshaft. A ten cent aluminum key. If your blade hits something, the inertia causes the weakest part to bend (the key). This changes the timing enough so the engine won't run. I know of what I speak. I attended the Briggs & Stratton small engine repair classes many years ago and worked as the service manager of a repair facility. There could be other problems, not saying it's the key, but it's common.
Bob
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Ooops, sorry, the key is on top at the flywheel. That's the one that changes the timing if your blade hits something.
Bob

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I picked up a mower that wouldn't start last year for $5 because the body of mine was rusted. Swapped motors, and recently gave the old motor away.
The guy who got emailed me back (I'd asked him to let me know) to tell me the key was broken and that's why it wouldn't start.
He got a great deal, I got a lump of metal out of my shop so everyone was happy.
The fellow I got it from told me he was using a de-thatching blade when it stopped running, so your diagnosis makes perfect sense to me.
djb
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
How do I find this bent key? ..... I won't find it taking off the blade right? .... Is there a manual online .. cause I have no idea where the flywheel is or more importantly where the key exactly is ???

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
First thing is to check for spark. Pull the plug wire off, put a screwdriver from the wire to ground but leave a 1/4 inch gap. When you pull the rope, a spark should jump the 1/4 inch gap. No spark, it probably isn't the key. If the key is bent, you'll still have spark but the timing will be off. The flywheel is under the shroud. At one point on the shaft there is a slot and at that point the flywheel slot should line up perfectly. If one is off from the other, the key is bent. Getting the flywheel off requires a puller or else you'll damage the flywheel. I'd suggest the manual if you get in this deep. If you were not cutting rough stuff and didn't hit any rocks or tree branches before stopping the mower, then it probably isn't the key. Someone else suggested using starter fluid available at an automotive store and that's a good suggestion, cheap and easy. I think the manuals are available directly from Briggs & Stratton or through one of their dealers. I've also seen their small engine servicing course but that was a few years ago. No, you don't take the blade off to change a key, long day, my tired brain wasn't thinking.
Bob

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
xeroid wrote:

Do you have spark? Tony
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
There's always a spritz of starter fluid into the carbuerator. If there's spark, it ought to start.
Works every spring for me.
--
Ron Hardin
snipped-for-privacy@mindspring.com
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Gas works just about as well.
Bob

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Un"fix" the adjustments. Check for spark. Make sure the blade is on tight. (It is part of the flywheel for some models.) If it sparks but doesn't fire, squirt a little gas into the carb and try again. If that works, it is a fuel problem.
More refs. http://www.small-engines.com / http://repairfaq.ece.drexel.edu/sam/lmfaq.htm
Bob
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.