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-6a engine mount wear

It's condition inspection time again and it looks to be not so good this year. Over the last year I have flown just over 200 hours and in that time I have managed to install a rub mark on my engine mount. I found that the left exhaust pipe has been rubbing the engine mount where it exits the engine cowl and doing quite a bit of damage. The rub mark mics out at 0.029" deep. I am sure this is a grounding measurement, or at least it's grounded until someone can give me guidance on what is acceptable. I am running a Lycoming O-320-D2J 160hp engine with the vetterman exhaust. Does any one know what the wear tolerance is or where to find it ? Can this be repaired and by who ? or does it mean I'm buying a new engine mount ? Thanks in advance
 
You should call Vans for guidance.

I found this type damage on one mount while performing an annual, not quite as deep as yours & had a welder fish patch a 4130 piece over the damaged area with TIG. Exceptional welder, he was able to do it on the plane. After re-painting the area, I attached a bit of baffle material to prevent future damage from the exhaust. Each annual the baffle material is removed to confirm no further damage is occuring.
 
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Thanks Ralph,
I talked to the tech rep and sent pictures. He seemed to think it was able to be patched but would check with the engineers and let me know. I guess I’ll start pulling engine since it will have to come off either way. Unfortunately the option of being repaired in place won’t work for me. Thanks again
 
The tubing is 3/4 x 0.049" 4130, so a 0.029" deep "notch" is a major structural defect.

Let us know how it gets fixed.

The AMT handbook even has a paragraph on engine mount repairs - end of this text - http://content.aviation-safety-bure...1-amt-airframe-vol-1/sections/chapter5.php#13.

Key bit here -

The preferred method to repair an engine mount member is by using a larger diameter replacement tube telescoped over the stub of the original member using fish-mouth and rosette welds. 30° scarf welds are also acceptable in place of the fish-mouth welds.
 
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