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Discussion Starter · #1 ·
fast enough to start. This is a 25HP YardMan by MTD that I have used for several years. It has always been slow to start simply because the batteries don't seem to turn it over as fast as they should. When the starter kicks in, it may spin (and it will start) or it may not spin. I have added a new starter and a new battery with 350 CCA. Now the starter terminal gets very hot and it stills doesn't want to spin. The engine is Briggs model 445777 0231E1. I have thought about putting a heavier (#6) starter wire from battery thru. solenoid to starter but I fear this will only burn up the starter. Any suggestions on how to free this monster up?
Thanks to all.
WTC
PS
It is called "old yeller" because of the hood and wheel color. I name all my mowers. Doesn't everyone?
 

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You need to adjust the valves. The valve adjustment is critical because there is a compression release on the valve cam that causes the compression to release allowing the engine to turn over easier. Otherwise it will hang up at the top of the compression stroke.
This is a common problem with Briggs lawnmowers. New battery won't help. Try this. Hold your hand over the carburator intake and then crank the engine. If it starts, it's the valve adjustment. When it can't get air to compress, it turns over easy anyway. Better wear a leather glove when sticking your hand over the carb intake - don't get burned!
 

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Hey ddog,

Nice to see you here and happy you've joined up with us...

Interesting observation about critical valve timing and the compression release. Something I hadn't considered in WTC's problem post.

Mark
 

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Discussion Starter · #5 ·
Hey ddog,
I have adjusted the valves and the old boy now starts. Yea! It still doesn't seem to get enough gas to start quickly but I suspect that this is another issue. Anyway, thanks very much for the "hand to restrict air" trick. I love it! I guess that I am just an old dog still learning new tricks. Thanks very much.
TC
 

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Good for you WTC
Glad you got that rig running. Best way to set valves is to first turn the engine by hand until one valve is pushed all the way down (open). Then set the other one to .004 inch clearance. Then repeat with the other valve. If you mess this up, you could have the engine start ok but end up burning valves because you set them too close. The different Horse power motors may differ on the setting. Some manuals specify different procedure.
 
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