Briggs& Stratton engine will not turn over
- Thread starter JimP2014
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The flywheel key looks intact but that means nothing. I'm wondering if I should pull the head right now or assume the key works. It looks intact. It looks in the correct location but who knows, but I'm thinking of moving on to spark fuel carburetor arena.
Jim
oldntired55
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glad i could point you in right direction... id be very curious to know how it turns out
oldntired55
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i was ready to pull the head, but my leakdown tester showed no leaks thru valves.. OR thru the oil fill tube. so i was certain valves & rings were ok. well, the only way to get "compression",,,, is there has to be a volume of air for the piston to 'compress"....you cant obtain that volume, if the valves are BOTH closed on the downward piston stroke. i think too many of us over think the basics of a 4 stroke engine... just remember one thing, with a leakdown tester, you are Pushing the air in, with a compression test, the engine supplies the air.
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oldntired55
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but, even now it seems i have strayed from the original problem in your post... "awful banging" noise... sounds internal for sure...
So many things have changed every single day. I can say right now 2 days ago there was no banging. There was just hunting and surging and then I blew out the spark plug. So I swap the cylinder head for a 14.5 horsepower. Briggs cylinder head and now the current problem is I turn the ignition key. I'm getting spark to the spark plug but the flywheel just turns until it runs out of battery power for the starter. I also just made a video not only of that but also with the valve cover off. What's going on where the Piston rods and the rocker arms and everything looks good and I'm going to try and upload that video very soon.
So to recap right now a very old cylinder head onto the 19.5 horsepower Briggs engine. Everything matches up except the 14.5 horsepower engine does not have the beefiness of the cylinder head for the 19.5 horsepower engine, but everything else lines up. The head gasket is in place. The valves are adjusted. The Piston rods are doing what they're supposed to do. The valve clearances I believe are correct but the flywheel just rotates and nothing else happens.
I'm trying to determine say without using a leak down test apparatus. What's going on internally with the engine so right now on July 9th around 7:15 a.m. at some point soon I plan figure out why the flywheel keeps rotating. The spark plug does have spark but the engine does not start. The flywheel just keeps turning but other than purchasing a compression tester I'm hoping that's all I need to purchase further. If I need this other test apparatus then I'm just hoping that I don't need it actually unless you can't figure out what's wrong unless you get a leak down tester too. This I don't know. Also, just to be clear, before I swapped in the old older cylinder head, there was no banging going on. It started up instantly and there was hunting and surging only. But the spark plug blew out because I destroyed the threads on the cylinder head by doing many many tests. So that's why I have a new cylinder head which is not brand new. It's from an older machine but it fits
Jim
Just to be clear, the awful banging went away say a couple days ago and I can't explain why. Maybe it had to do with carburetor cleaner. It is just very confusing and the symptoms change seemingly on a daily basis and I'm trying to figure all that out
It's not time to pull the flywheel AGAIN and also do not remove the head yet.
No need in guessing about things yet.
You already know the three things needed for a engine to try to run.
Since you do not have a compression tester you can do this test to feel for compression W/O removing the spark plug for now.
leave the key off and remove the spark plug boot/wire from the spark plug. (we are making sure the engine does not try to start while fingers are around the flywheel fan)
Turn the engine over by hand manually CW looking down onto the top of engine or by using a socket on the flywheel bolt.
Every other revolution of the flywheel you should feel the piston start having back pressure (compression and push itself through TDC) keep fingers out of the plastic fan.
This lets you know that the INTAKE valve is opening some and fully closing (sealing) and that the exhaust valve is holding compression.
If you do not feel any compression fighting you when manually rotating the flywheel, back the INTAKE valve lash off to .010-,012 and try same test.
If still no compression set the EX valve lash to .012 and test. If neither of these gets compression a valve is not sealing/seating.
Let us know what you find?
No need in guessing about things yet.
You already know the three things needed for a engine to try to run.
Since you do not have a compression tester you can do this test to feel for compression W/O removing the spark plug for now.
leave the key off and remove the spark plug boot/wire from the spark plug. (we are making sure the engine does not try to start while fingers are around the flywheel fan)
Turn the engine over by hand manually CW looking down onto the top of engine or by using a socket on the flywheel bolt.
Every other revolution of the flywheel you should feel the piston start having back pressure (compression and push itself through TDC) keep fingers out of the plastic fan.
This lets you know that the INTAKE valve is opening some and fully closing (sealing) and that the exhaust valve is holding compression.
If you do not feel any compression fighting you when manually rotating the flywheel, back the INTAKE valve lash off to .010-,012 and try same test.
If still no compression set the EX valve lash to .012 and test. If neither of these gets compression a valve is not sealing/seating.
Let us know what you find?
I am sorry I have a compression tester when I don't have is called the leak down tester which is different. But you think I should test for compression because the compression tester I just bought I own that