Nothing

[Oarhead]

I bypass them all of the time for testing purposes.
It gets put back functional when done repairing.

Thank you!

 

[Oarhead]

So got the head off...perfect....kinda pissed to change it. It's that nice. Valves moved smooth, push rods straight. Piston moves freely....no noises. My greatest weakness....electrical..

 

[slomo]

Replaced battery, fuel and oil, fuel lines, plug, coil.

Most all new parts require testing.

Spins Like no plug.

Valve stuck open or broke rod? Lifted valve seat possible.

Plug looks new. Not wet, doesn't look like it fired at all.Died like I shut off the key.

Lack of fuel reaching the plug. Or could be the carb solenoid if it has one.

No noises . Was at slow idle backing out.

Not recommeded to idle down a splash lube engine. Hope yours has an oil pump.

Was running fine. FResh oil change.

Great. Ever cleaned the block cooling fins yet? This is a yearly item in your engine manual. Remove the top metal engine cover and investigate. Some Dawn soap and scrub brushes. Compressed air works good. Clean the block like this is a new engine.

Seat switch disabled.

We've covered this already.

I also have a dyt 4000 (given to me),i use to get my disabled ass around the property, that had an 18.5hp. Got switched with what they.call a replacement 19hp b&s. Needed a head ga sket twice. Blown in same spot, directly across from plug, Made a repair. Runs beautiful.
I drained the oil looking for metal found none. Gonna pop the head, see what's up

IF the head gasket is toast, you will need to lap the head and the block area where the head sits. As in taking a sheet of plate glass and some 220-400-800 grit wet/dry paper to it. Let the paper DO ALL THE WORK. Straight edge wouldn't hurt here.

 

[StarTech]

Well we tried to save you some frustration by having you do some non-invasive tests first but you went straight to tear down. So far I only seen only shatter flywheel taper but that can happen too.

Plus I have already two engines this year where the only problem was bad plugs.

 

[Oarhead]

I'd put a a half teaspoon of gas into the plug hole, put the plug back in and see if it will fire. You can also turn it over with the plug out before you do that and see if you have compression. Use a compression gauge but if you don't have one put your thumb over the plug hole - you'll feel it push your thumb off. You can also use a spark tester or timing light to see if the plug is firing - meaning you have spark. I respect what others suggest but before you take things apart you first figure what is missing of the three things needed to run

Spark
Fuel
Compression

So I got the head off. Gasket looks like new....kinda pissed at replacing it...anyway valves move as they should, push rods a5re nice, take a closer look 2moro. Piston moves as it should with no noises. Inside, where valve stems reside, pretty gunkified. Ccleaned it well. This machine was due a good tune-up...no happy if this is electrical. Not my strong suit.

 

[mmoffitt]

Some of this amazes me....people ask for your help and then totally disregard and or do not listen..Thanks for the wealth of knowledge that all so feely give!! I have learned so much....by doing things the best practice way SAFELY! everyone be well!

 

[rabass]

yth18542. Backing out of barn, died. Just shut down. So being that time I replaced everything, coil included. Turns over like crazy. Plug looks like it was just unpackaged. No fuel or spark. Nothing but turning over. Disabled seat safety, nothing. Watching grass grow....ugh. Any help out there?1

Sounds like a sheared flywheel keyway

yth18542. Backing out of barn, died. Just shut down. So being that time I replaced everything, coil included. Turns over like crazy. Plug looks like it was just unpackaged. No fuel or spark. Nothing but turning over. Disabled seat safety, nothing. Watching grass grow....ugh. Any help out there?1

Sounds like a sheared flywheel key, pull the flywheel and inspect

 

[SamB]

I for one am confused
"Replaced everything"
means exactly what ?
"Turns over like crazy "
means strong or really fast like there is no spark plug in the engine ?
"No fuel or spark "
plug is dry and does not throw a spark ?
"Died , just shut down"
Like it ran out of fuel or like you turned the engine off ?
Did the engine stop really quickly or seem to revolve for a long time with no power ?
Did you hear a bang just before it stopped ?

How was it running the last time you used it and when was that ?
From what you have written could be as simple as a dud safety switch to as complicated as a broken con rod or if you are really lucky both + some more

A bit flip,bertsmobile1,but in my case:

 

[Oarhead]

A bit flip,bertsmobile1,but in my case:

Cute!

 

[Oarhead]

ha!!! Now it's both tractors. One races like it's gonna blow up....new head gasket, plug, filters, oil, coil, valves adjusted. B&S 18.5 hp, 33r777.
Tractor2. Was running normally this AM...Then half hour later only runs smoothe when throttle fully engaged, (choked), on normal high, (rabbit throttle), chokes spits shuts off. I truly hate carburaters. The only plusible explanation maybe the brand new gas I put in it last nite. 5 gals of bad gas will piss me off.....