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Briggs-Fan, Small Engine Technician
Category: Small Engine
Satisfied Customers: 1264
Experience:  over 15 years experience in small engine repair, multiple certifications
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I have a &S 12170231410190100257 3.5 hsp. engine on my

Customer Question

I have a B&S 12170231410190100257 3.5 hsp. engine on my Snapper Mower. It usually faithful and starts on two pulls. I have been using it all summer. Recently, I started it normally and started mowing. After 20 mins. it stopped. All my attempts to start it failed. I took off and changed the air cleaner. I used starting fluid and no go. All I got was a small cough out of the carb. Later. I changed the spark plug and checked for park. I had spark. I took off the cover and cleaned the magnito and magnets anyway. Still no go.
What is next ?
Submitted: 2 years ago.
Category: Small Engine
Expert:  Briggs-Fan replied 2 years ago.

Hi my name is ***** ***** welcome to just answer. Next check compression . Being a 4 cycle engine it needs 60 lbs of compression or higher to run , check the compression before starting it , if it has 60 or higher great , then after it dies carefully remove the hot spark plug and check the compression again , if it 55 or 50 you know it's a compression issue , most likely caused by the valves etc .

Customer: replied 2 years ago.
Please note that the engine will not start at all. I cannot check the compression according to your instructions.
Expert:  Briggs-Fan replied 2 years ago.
it won't even start cold . You don't need it to run to check compression , all you need is a compression tester which screws into the spark plug hole and when you pull it the compression will show a reading on the gauge
Customer: replied 2 years ago.
If the compression is less than the level you described what do I do Next ?
Expert:  Briggs-Fan replied 2 years ago.
I would check the valves first , see if it needs a valve job , and then if they are ok I'd look at the cylinder etc
Expert:  Briggs-Fan replied 2 years ago.
Hi this is John , just checking to see if you have been able to check the compression on your snapper yet