Engine lets out a puff of smoke but doesn't even sputter when attempting to start

[jetpackjbd]

Narrowed it down to the magneto, ordering a new one. Hope this fixes it, only thing that would make sense.

 

[slomo]

Air, spark, fuel and compression. Back to the basics.

Any and all new parts will require testing. New is not new these days.

Most likely the carb and fuel system is filthy. Valves never been checked. Block cooling fins neglected as in never cleaned or looked at.

 

[slomo]

Narrowed it down to the magneto, ordering a new one. Hope this fixes it, only thing that would make sense.

New mag will need to be LOAD tested. As in taking an old plug. Gap to 1/4" or 0.250", super wide. Ground the threads and check for healthy spark.

 

[jetpackjbd]

New mag will need to be LOAD tested. As in taking an old plug. Gap to 1/4" or 0.250", super wide. Ground the threads and check for healthy spark.

Will do, but for now I'll just be happy to get any spark at all...

 

[jetpackjbd]

I've got spark! But I think my old magneto may have been fine...
I took off the carburetor today and sprayed starting fluid directly into the hole where the carburetor would connect. Ended up with a tiny fire and an engine that still showed no signs of life...

 

[slomo]

So you have air, fuel and spark. Still no signs of life. Remaining factor is compression. Time to open her up to check valves and piston/rod.

 

[jetpackjbd]

It is a case of elimination
By removing the belts we eliminate the mower putting a drag on the engine
When running along a slope it is easy to have the oil pick up in the air so the oil pump is pumping foam or just air
The top bushing area has a small dam of oil and if it is not kept full then the crankshaft can sieze in the crankcase
Or the starter motor can jamb which normally releases by rotating the flywheel backwards.
A 2002 model is well past its use by date but we are here to fix things if that is at all possible
Usually side valve engines loose valve lash on the exhaust because the valve seat burns away
All side valve engines do this and when it gets chronic the exhaust valve no longer seals
It is a PIA on side bangers to check because the valve chest is behind the carburettor.
In the workshop I have both a bore-o-scope & a leak down tester to check for this .

If the valves can close & the timing is good then the engine will fire when you put fuel down the plug hole
If it does not fire then either the valves are not sealing or the flywheel has spun on the crankshaft so the spark is out of time
or the piston is no longer going up & down.( check with a pencil poked down the plug hole .)


If the engine had a temporary seizure & you forced it free by turning the flywheel then there is a good chance the timing key broke or the con rod broke

So try what has been sugested and come back

Whelp, you were right. I finally took the engine apart a bit and discovered the piston no longer moves, but if I push it back manually it moves a tiny bit when spinning it. I also discovered the oil was very black, despite my initial findings. Last thing to do is check the crankcase and maybe attempt to replace the conrod... Thanks for the help

 

[jetpackjbd]

So you have air, fuel and spark. Still no signs of life. Remaining factor is compression. Time to open her up to check valves and piston/rod.

Yup. Split conrod.

 

[Tinkerer200]

And next time post the engine model number so we know what engine we are actually talking about.

Walt Conner

 

[slomo]

Yup. Split conrod.

Another satisfied customer.