meritflyer
Well-Known Member
So, I have a pre-buy done today on a Turbo Arrow IV that I am considering buying and here is the mechanic's biggest concern.
In March '09, the turbo failed in flight. One of the turbo blades completely came apart and became a pile of metal dust.
The plane was landed uneventfully and taken in for the service to repair.
The plane received a new turbo after the cylinder walls, compressions, manifolds, and piston crowns were all inspected via boroscope with no defects. The turbo was replaced.
Now, the fun part.
The mechanic that put the new turbo in advises the oil needs to be changed every 5 hours for atleast 4 changes. The first three yield non-magnetic metal (not a good sign I presume) although he notes the metal is a result of the turbocharger failure.
In the last 10 hours, it's been clean including today when the mechanic cut open the filter during the pre-buy. The concern is, that there are metal parts floating around in the engine and may not be able to be detected and could cause piston and crankshaft failures (hope I said that right).
The owner is confident that it's not an issue as the metal in the filter was a result of the blade. The mechanics are being cautious but suggesting that it's probably not an issue but there's no real way to tell. They are going to pull the oil suction screen tomorrow for another 'gut' check but all in all, they said there's really no way to tell immediately if there's metal in the engine.
I need your input on this, folks! What do I do?
(I also posted this in Tech Talk. Can you Mods please leave it here too?)
In March '09, the turbo failed in flight. One of the turbo blades completely came apart and became a pile of metal dust.
The plane was landed uneventfully and taken in for the service to repair.
The plane received a new turbo after the cylinder walls, compressions, manifolds, and piston crowns were all inspected via boroscope with no defects. The turbo was replaced.
Now, the fun part.
The mechanic that put the new turbo in advises the oil needs to be changed every 5 hours for atleast 4 changes. The first three yield non-magnetic metal (not a good sign I presume) although he notes the metal is a result of the turbocharger failure.
In the last 10 hours, it's been clean including today when the mechanic cut open the filter during the pre-buy. The concern is, that there are metal parts floating around in the engine and may not be able to be detected and could cause piston and crankshaft failures (hope I said that right).
The owner is confident that it's not an issue as the metal in the filter was a result of the blade. The mechanics are being cautious but suggesting that it's probably not an issue but there's no real way to tell. They are going to pull the oil suction screen tomorrow for another 'gut' check but all in all, they said there's really no way to tell immediately if there's metal in the engine.
I need your input on this, folks! What do I do?
(I also posted this in Tech Talk. Can you Mods please leave it here too?)