wally
Well-Known Member
I just got the bad news about my crankshaft.
This is an old engine (O-320 Lycoming) that came with the Pitts project. I didn't know much about engines when I bought it but I do now!
Supposedly the engine was ready to put on the airframe and run. Well I later found out (after I bought it) that it had been put toghther about 25 years earlier and never run. I also learned that the lightening holes in the crankshaft flange (that I could see but didn't know at the time) is NOT a good thing on an aerobatic airplane. It should be a solid flange.
So last year I decided when it was closer to mounting the engine time, I shoud at least take it apart and have a look inside. I had found a place that would give me about $1500 trade-in if the crank could pass service bulletin 505 (inspection in the front hollow area) and could be machined back to serviceable condition.
Well I just got the phonecall - it is cracked at the slinger ring - near the front flange. That means it is now only good to tie a rope on and use for a boat anchor! Oh, Well! The good part is I found the problem now - A Pitts does not make a good glider.
The case also had fretting wear - where the two halves meet and clamp together. If this is not fixed, then when assembled, the main bearings get squeezed too much and also will destroy the engine. I sent the case to DivCo to be re-surfaced and line-bored to fix that. And the hydraulic lifters inside were stuck. This engine should never have been put together.
One good thing, the cylinders do look like they have been reworked and they do have new pistons and rings.
So this thing is gonna cost me about $5000 more than I thought 2 years ago when I started. The new crank alone is $3700.
Just thought I would share,
Eally
This is an old engine (O-320 Lycoming) that came with the Pitts project. I didn't know much about engines when I bought it but I do now!
Supposedly the engine was ready to put on the airframe and run. Well I later found out (after I bought it) that it had been put toghther about 25 years earlier and never run. I also learned that the lightening holes in the crankshaft flange (that I could see but didn't know at the time) is NOT a good thing on an aerobatic airplane. It should be a solid flange.
So last year I decided when it was closer to mounting the engine time, I shoud at least take it apart and have a look inside. I had found a place that would give me about $1500 trade-in if the crank could pass service bulletin 505 (inspection in the front hollow area) and could be machined back to serviceable condition.
Well I just got the phonecall - it is cracked at the slinger ring - near the front flange. That means it is now only good to tie a rope on and use for a boat anchor! Oh, Well! The good part is I found the problem now - A Pitts does not make a good glider.
The case also had fretting wear - where the two halves meet and clamp together. If this is not fixed, then when assembled, the main bearings get squeezed too much and also will destroy the engine. I sent the case to DivCo to be re-surfaced and line-bored to fix that. And the hydraulic lifters inside were stuck. This engine should never have been put together.
One good thing, the cylinders do look like they have been reworked and they do have new pistons and rings.
So this thing is gonna cost me about $5000 more than I thought 2 years ago when I started. The new crank alone is $3700.
Just thought I would share,
Eally
