Hatched riding mower

[moderation]

I need to know what has happened. Our riding lawnmower is hurting. A 12.5 Briggs that was running good, my wife turned the throttle to idle, after a short time of cutting, then turned off the key. A backfire and that was the end of it. It turns over very easy and back fires only after turning for 10 or more seconds. Compression check did not even register. Lots of oil in the OHV cap. When I checked it was coming out from the valve guides at a high rate when turning over.

This machine is about 18 years old and only used as a backup and sometime pasture mower. I think it’s hatched, but before I junk it (it’s not worth putting money into) I thought I would ask and see what anyone thought.

PS: Who accepts something like this in the Duluth area,the landfill or some other spot?

[mnflyfisherman]

While this is just a guess, it sounds like a piston or ring failure. I would imagine you might make a few bucks if you took it to a salvage yard. Call around and see if they'll take it before you truck it out there.

--mnflyfisherman

[Surface Tension]

I'm thinking the backfire that happened at time of shut down was the last straw to a problem that was going to happen sooner then later. Hot engine caused from grass or seeds in the flyweel screen. As a result, hotter then normal muffler ignited fuel thats still being pumped as the engine winds down at shut off. Maybe even a small carb gas leak and into the crank/higher then normal oil level. Carbon build up, heat, pop = valve problem.

The piston and rings are probably still good, thats whats pumping the oil past the valve.

Take the spark plug out and slowly turn it over by hand.

One of the valves isn't seating. If your lucky it from carbon and can clean it out.

Worst case you can bring it to Rice Lake Small Engine or Willmans and get their opinion.

[moderation]

Thanks Frank : the oil level is normal, yes the engine could have been hot because on further inspection there was a mouse (rest in peace) nest under the flywheel cover. After removing everything is when I tried to start it again and had more backfires after turning over for 10 or more seconds and saw the oil shooting from the valve guides. A friend of my wife has a son into trying motor repair so I’ll probably give it to him and if he finds out it’s too expensive and can't make any money off of it I’ll take it back and bring it in for disposal.

[foxhunter]

bent valve. same thing happened to mine this summer.

[Bobby Bass]

I need to know what has happened. Our riding lawnmower is hurting. A 12.5 Briggs that was running good, my wife turned the throttle to idle, after a short time of cutting, then turned off the key. A backfire and that was the end of it. It turns over very easy and back fires only after turning for 10 or more seconds. Compression check did not even register. Lots of oil in the OHV cap. When I checked it was coming out from the valve guides at a high rate when turning over.

This machine is about 18 years old and only used as a backup and sometime pasture mower. I think it’s hatched, but before I junk it (it’s not worth putting money into) I thought I would ask and see what anyone thought.

PS: Who accepts something like this in the Duluth area,the landfill or some other spot?

Demo-Licious in West Duluth wil take it, Scrape yard will want you to remove tires, and all fluids, gas/oil. demo will take it as is.

[Splake]

Might not be bent. My exhaust valve got stuck open do to carbon build up. There is an access panel to the top of the valves and I just twisted the valve stem with a pliers. It popped back. Napa had the gasket and I put in some sea foam and I'm going on 5 months!

Splake