May 2018-
Hard landing damaged the landing gear (prop strike included) and subsequent wind damage caused my Cub to spend some significant time being rebuilt this summer. 0-320 A2B 150 HP Engine was not running when plane came to ground. It is my belief engine stopped running due to carb ice- most all causes of why an engine would stop running ruled out and all other signs/symptoms point towards carb ice. I had a reputable ANC shop perform the repair work. Total damage came in near total hull value of the insurance with the recovery cost factored in as well.$90k (lucky to have). One wing totally rebuilt with new ribs, new spar, new struts, the other wing new front spar and few leading edge cuffs. Rudder damaged beyond repair so replaced.
Due to my desire to keep the airplane and based on word of shop, the complete tear down of engine was not recommended, just the prop strike AD 91-14-22. I was told the flange and main bearing were measuring 0, 0 which was part of why full teardown was not recommended. I interpreted that as there was no measurable change to either the crank or the flange from prop strike and took them on their word.
So, I authorized the repair per their quote and attempted to patiently wait to get my plane back. I kept in close contact for progress updates and to get general idea of how repair was going. I didn't ever really get the warm and fuzzies during conversations with the shop. I more or less felt they were telling me what I wanted to hear vs what was actually happening in reality. Airframe went into a jig which I felt good about as far as frame goes. When I went to pick the plane up in Sept. I gave it as thorough a once over as I have competency in (not an A&P but consider myself very attentive and competent in regards to my own Super Cub). I requested a test flight after the plane was put back together. After test flight the flight examiner noted the plane had a left turning tendency with ball not in the bubble so some manipulation was made to vertical fin to correct. Still not certain it is as true as I would like but I'm getting somewhat impatient with working with this shop any further. At time of repair I was told the carb was not necessary to replace nor was it in the quote which I found strange, considering the carb box was bent and damaged from nose cowl coming into contact with ground as well during landing. In other words the carb box was bent and damaged beyond repair which connects direct to the carb and I didn't see how one would not be concerned over the forces exerted on the carb in this situation. The shop ensured me this would be a non issue when they fixed or repairied the carb box.
During the 2-3 hours flying around the ANC area I noted the RPM drop during carb heat application was more than what I grew accustomed to previously. I became used to a 100 or so RPM drop but now the plane was dropping 200-250 RPMs at times and this was alarming as I had to lean the mixture to get it to run happy. Even more alarming when down at low power settings! I mentioned this to the shop before I departed for Juneau, where the plane resides, and I was assured the additional drop was due to tighter fitting air filter/carb heat box lever etc.
I then got back to Juneau and was able to take a more invasive look at the engine, etc (which I now know I should have done before departing ANC and paying for the repair). Before I picked the plane up I asked how the fuel tanks and fuel lines were being cleaned from what undoubtedly was sand intrusion from the wind damage on the beach during incident. I was assured they were cleaned. I then sumped sand from my wing tanks the entire flight back to Juneau. Very upset that I had been lied to especially since this was a specific question I was assured had been taken care of. This then just opened the door for doubt regarding any of the other things I had been told. I got the cowling off the engine to see
if anything stood out with regards to the additional RPM drop during carb heat application. This was when I noticed the carb box was not replaced but rather "repaired", which it wasn't (photo attached). The air filter mounting flange was visibly bent, the air filter subsequently was over tightened to compensate for bent flange therefore crushing the air filter. It never properly sealed but rather caused soot to build and get past air filter. This bent flange also gouged the new nose bowl cowl.
The washers between bolt head and carb were over tightened and bent (don't think this is a standard for this type of washer so I viewed this as unprofessional). The flap lever hinge on one wing has a close tolerance for one of the wing ribs and the attention to detail can be seen in another attached photo. It looked like they used scissors to cut the sheet metal
and left a bunch of rough edges and flaps hanging in area. Also very unprofessional. The #4 intake riser
was clamped on the WRONG side of the rib coming out of the oil sum (photo attached).
So, when I generated my list of discrepencies for a $70k invoice the exact day my plane got put back in its hangar, one can imagine the dissatisfaction and distrust. I told the shop the carb box needed to be replaced, the carb replaced due to
the discomfort in its reliability and operation based on the additional RPM drop I had observed in the 10 hours flying the plane home. The carb box and carb have since been replaced which now has the engine much happier than previous running condition.
I did an oil analysis of the oil after approx 18hrs running time after coming out of the rebuild. I got the results back from oil analysis the other day and now I'm worried something else may be wrong. The levels of aluminum and chromium are double the previous readings. Is this possibly due to new crankshaft gear and retaining bolt? Any other work due to the AD compliance that could/would cause increased aluminum and chromium wear for a period of time after parts replacement? I'm hoping for a confirmation or recommendation based on recent oil analysis due to my distrust of this shops work. I plan to fly another 20 hours and then do another oil analysis. Problem is, is that it might be a while before I can put another 20 hours on the plane as I live in a different town than the plane for the time being. The below photos are really basic things and if a non mechanic can identify them, then certainly a shop who has been working exclusively on Cubs for 30 plus years is putting this type of work out there is reason to doubt their work.
Any other thoughts or things to be on the lookout for as time goes by would be appreciated. Especially since there are things they did which I cannot put my eyes on at this time.
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