Probably gonna have to insert several words. You say, "it quit starting as easily" and "it still eventually started". By this, do you mean that it began refusing to turn the engine (cranking) and instead seemed like the engine just did not want to spin??? Or did it spin easily and just did not want to "fire up and run"?? From your limited description (and no mention of engine brand/model) my first impression is that your engine is in dire need of .....valve adjustment. Post the engine brand and model number and we'll proceed with caution.

Try to find where the black (ground) cable attaches to the frame, or wherever. Clean this area of any rust and dirt, and reattach the cable,, making sure there is no bluish dirt in the cable housing. Clean the posts where the cables attach to the battery! Clean where the ends of the red (+) cable attaches to the solenoid, and to the battery. Clean the other red cable from the solenoid to the starter.
If either cable has the bluish corrosion in it, best to replace it/them.
Use new bolts, nuts, flat and lock washers when re-connecting the cables to the battery.
If that fails, jump the battery from a known good battery, like in your car, or truck. Or, jump direct to the bolt on the starter, with the negative cable to the frame of the tractor.
Now, if you installed a new battery, it might not have been fully charged, so it might be a good idea to charge it overnight, with a good portable battery charger!
HTH: Rustyj

I'll betcha taking the plug out will spin. Looks like another B&S valve adjustment. Walt?

That should be a Briggs 31P777-0348-E1

VALVE Adjustment time!

There are numerous posts in this forum about Briggs OHV engines being hard to crank over. You;ll probably have to go back a few weeks to find one.
Find one of them and Walt has posted his email address and will send you a detailed procedure on how to go about it.
It's WELL worth the price, which is free.
He also lists some caveats of what NOT to do.
You have to email him first, so he can just paste them in and hit reply.

Here is the additioanl information requested in case it is something else, then I will go find Walt and see about getting the instructions for a valve adjustment.

It is a Briggs and Straton 18.5 OHV engine. I am unsure about the model number but on the side of the engine on the red plastic cover are 2 lines one reads "31P7770348E1" and the other reads "040121ZD53658". It does not specify what they are but thought I would go ahead and provide those to you.

It does seem like it is trying to turn but having trouble more so than anything. When I jumped the starter directly it popped up what I guess is the flywheel or something and it lined up with the gears of the main engine but couldnt turn it. There is also a noise like something is rubbing when I try to start it.

How can this work fine all summer and then just go kaput?

Good numbers. OK, the "thing" what "pops up" is known correctly as the Starter Drive Gear Assembly. Starter Drive will suffice. It is nearly universally accepted to refer to this component as the "Bendix". The "rubbing noise" you hear is the combined sounds of the starter armature "growling" because it is stalled, and the slow motion sounds of compression changes (which normally happen so fast you can't pick them out) in the cylinders. And remember....it did not go kaput "all of a sudden", it gradually became reluctant to start. It has only just now crossed the line from "reluctant to crank" to "I will not crank no matter how much profanity you heap on me". If the weather has turned cooler in your area over the past few weeks, that is likely why it SEEMS as if the problem "just occurred". Cooler temps will further reduce critical valve clearance to the point that the "compression release feature" of the engine cannot automatically lower combustion chamber pressures during the cranking phase of starting the engine. Get Walt's instructions, study them carefully, and decide if you want to adjust them yourself, or if you feel like "farming it out" to a shop. Good luck.

Just curious how is the compression release feature accomplished?
Paul

On THIS engine, there is a "bump" on the cam lobe at TDC.
Too much lash and the valve doesn't get bumped open when cranking to relieve compression.
Thus, the valve adjusting procedure DOESN'T use TDC.

So basically it just works to relieve compression when it is cranking slowly as compared to higher rpm's when it would not open the valves long enough to affect engine running.
Neat.
Paul

Not really, PITA cause you have to keep the adjusted right. Older engines without them started just fine and so does kohlers. why do we need it??? MMMMMmmmm only thoughts are cheaper starters and low CCA batteries come to mind.

even older engines occassionally had to have valve lash adjusted that had OHV but nothing like the new ones IMO. I have adjusted my older vangaurd once in 19 years and that was cause of the rattler I got tired of hearing. But it did start better also. Not a better Idea IMO give the produce a bad name due to the no starting problems on so long after the warranty runs out.

",,,,just fine and so does kohlers....."
What makes you think Kohlers don't have one?

From theKohler Command (V) manual-
"Operation
The ACR mechanism consists of a flyweight, spring and pivoting control pin assembly attached to the gear on the camshaft. At cranking speeds (700 RPM or lower), the control pin protrudes above the exhaust cam lobe. This pushes the exhaust valve off its seat during the first part of the compression stroke. The reduced compression results in an effective compression ratio of about 2:1 during cranking.

After starting, engine speed increases to over 700 RPM, and centrifugal force overcomes the force of the flyweight spring. The flyweight moves outward, pulling the arm of the control pin, so it pivots into the âÂÂâÂÂrunâÂÂâ position. The control pin no longer has any effect on the exhaust valve and the engine operates at full power.

When the engine is stopped, the spring returns the
flyweight lever and control pin assembly to the compression release position ready for the next start