Since Mark & others have got my attention re tightening of prop bolts, I thought I'd make a report.
On Lonnie Prince's website there is a downloadable .PDF page regarding the installation & maintenance of his props. http://www.princeaircraft.com/documents%5CPAC_Torque_Procedure.pdf For my bolts of 5/16's, he calls for 12 ft. lbs. of torque. Checking my current values, they were all around 9-10 lbs., so they had loosened in the 69 hours that it's been since I replaced the Sterba. But they had all loosened equally - there were not some tight and some loose. But they were'nt really "loose" - I mean the prop wasn't flopping around by any means. The wood substrate had lost a little moisture since the prop was new - understandable. Before I found the .PDF file I had put in a call to him (and then called right back to cancel the call since I immediately found the file on his site once I'd looked). But he called me this morning anyway and we discussed props & other things. He built a KR-1 years ago and has a special interest in them. He asked me where the Gathering was going to be held this year and I said it was under discussion, but would probably be at Mt. Vernon. He is in Toledo and said he would fly his Navion down to visit, so once a date and place is certain I'll let him know. I asked him about the consequences of not re-torqueing prop bolts. He said the first consequence would be the "burning" of the prop bolt holes. Once that process starts, the next major indicator would be some serious prop vibration. I assume the vibration would get bad enough that nobody would run the prop to the point of blade failure. Props that suffer "hole burning" need to be sent back for some major work. I didn't ask him what, but I assume one would need to drill the holes to a larger diameter and go to larger bolts. Not only are Prince props excellent, the customer service is just as good. Mike ____________________________________________________________ You're never too old to date. Senior Dating. Click Here. http://thirdpartyoffers.juno.com/TGL2141/fc/BLSrjpTQbQXDiBHlZrcxTFSNY25MdwFsVAdiuePI1HXaTQ14YSagwnfAnNu/
