Engine Gurus Unite -> I need HELP!

[bob_nj]

Yes the motor did run fine. I haven't flown this plane regularly, but I keep notes on each plane and engine and
there's no entry for anything like this previously.

It did have compression and started well, and no, I am delinquent in not trying a new ignition.
I'll clean up the piston and jug, get rid of the blow by on the piston, and try another ignition today with the
original ring.

Thanks
Bob

 

[2walla]

Also try mixing up a fresh batch of fuel. ..

 

[bob_nj]

Will do.

In my own defense, I guess I was following some recommendations from Frank.

Here's a snippet from his latest email -->

At this point Bob, you need a ring for sure. Low compression will cause all mentioned problems along with poor reed seal on reed block.

More to follow...

 

[Aviatorplus]

1. Have you tried a new hall sensor, a bad sensor can do weired things that seem like fuel issues

 

[bob_nj]

No I have not.
Good call.
I'll add it to the list...

 

[49dimes]

1. Have you tried a new hall sensor, a bad sensor can do weired things that seem like fuel issues

About time you made it over here.

 

[bob_nj]

Here's the latest.

Original symptom was at WOT throttle engine would peak and slowly lose rpm and quit.
Could not tune that out with the needle.
At the low end, it was sloppy rich.
Could not tune that out with the needle either.

At that point, and before today here's what I did.
Nothing below made any difference in the symptoms above.

Different IBEC
Rebuilt DLE carb (New Gaskets, Screen and Diaphragms all around)
New Carb
Trued up the reed cage and carrier as they were not true/flat. At that point the reeds would hold water and looked good.

Things I tried today.

New stock ring. (Waiting on a Bowman)
New Ignition
Different Ignition Battery (Hooked Direct)
Different Hall Sensor
Different Fuel Tank
Different Fuel
AC Delco Gasket Coating (In case of air leaks)

The only thing I haven't tried are new reeds.
Not sure at this point it's the issue, but I haven't tried it.
I'm kind a worn out

I haven't flown this plane regularly, but in the past it has been fine.
Don't remember exactly when the issue became apparent, but during the summer I remember
a day at the field that was very windy.
Since this is a big profile, upon landing and while idling, the wind picked up the hind end and it went
a$$ over tincups just sitting there.

Maybe the fact that it was running at that point, did something to the crank position.
A proverbial prop strike.

Not sure whether or not to send it in, or pack it in

Thanks for all of the help, support and ideas.
What a long, strange trip it's been...

Take care
Bob

 

[49dimes]

Hey Bob. Do not waste a good bowman ring on it. I did see someone recommended a new cylinder. I would get a new piston and cylinder for the new bowman ring. They are cheap and you basically have a new engine to break in. You simply have a worn out power pack. The tolerances on the cylinder and piston are excessive. The crankcase pressure oscillations are erratic causing your issue along with the poor fitting reeds.

 

[49dimes]

Also something to check because it affects crank pressure is the seals on the ball bearings. They can deform and loose their sealing effect typically from heat from the engine.

 

[Aviatorplus]

After reading though the whole thread, it sure sounds like a plugged or partially plugged pulse port to me, especially since it still starts fairly easy assuming after its choked.