Looking for some input...
Piper Archer III, ( please don't flame me , .. with an O360 A4M with 800 hours since new. I am the original owner. Plane has been very reliable. One vacuume pump and an alternator are all that's been replaced. Mags overhauled at 500 hours, plugs at 400 and recently at 750.
Fired her up yesterday..all temps/pressures in the green. Run up and mag drop were fine. Rolled out on the runway.. everything was good till I was about a foot in the air when the engine sagged real bad. Put her back down and taxied back to the ramp. Acted like a fouled / bad plug... but she would not clear up. She was really shaking.... whew !
Pulled plugs... all were in excellent shape except #4 cylinder. " Ugly " pictures attached. Melted electrodes on top #4... bottom #4 same with the addition of busted ceramic insulator.
Had to get back home.. so other than looking to make sure the piston was still going up and down, this was the extent of my inspection...but heading back in a couple days.
Plan is to..
> Borescope cylinder
> Pull rocker cover and have a look
> Inspect intake tube for air leaks
> Check timing
This all happened in less than 15 minutes from start up to shutdown... strange to me... but maybe some of you guys can add some sanity to this.
Will have my A/P get involved but he is tied up for a couple weeks so I'm just wanting to get a bit of a head start.
Any input appreciated - Thanks !
Piper Archer III, ( please don't flame me , .. with an O360 A4M with 800 hours since new. I am the original owner. Plane has been very reliable. One vacuume pump and an alternator are all that's been replaced. Mags overhauled at 500 hours, plugs at 400 and recently at 750.
Fired her up yesterday..all temps/pressures in the green. Run up and mag drop were fine. Rolled out on the runway.. everything was good till I was about a foot in the air when the engine sagged real bad. Put her back down and taxied back to the ramp. Acted like a fouled / bad plug... but she would not clear up. She was really shaking.... whew !
Pulled plugs... all were in excellent shape except #4 cylinder. " Ugly " pictures attached. Melted electrodes on top #4... bottom #4 same with the addition of busted ceramic insulator.
Had to get back home.. so other than looking to make sure the piston was still going up and down, this was the extent of my inspection...but heading back in a couple days.
Plan is to..
> Borescope cylinder
> Pull rocker cover and have a look
> Inspect intake tube for air leaks
> Check timing
This all happened in less than 15 minutes from start up to shutdown... strange to me... but maybe some of you guys can add some sanity to this.
Will have my A/P get involved but he is tied up for a couple weeks so I'm just wanting to get a bit of a head start.
Any input appreciated - Thanks !
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