Posted by Martin Hill on Tuesday, February 21, 2012 @ 01:22 PM:
Can anyone help with some basic info?
Wheels - well undercarriage actually.
I have had my 5 for several years and always noticed a clunking noise from the undercarriage. I always thought it was the dampers but have now pinned it down to a forward/aft movement of the complete assembly. Basically play in the lock mechanism.
There is no damage or visible wear to the pawl or lock. The movement seems to be entirely of the pawl in the locking plate.
We had another 5 on the airfield so I gave its u/c a good rocking. It too moved. Maybe not as much as mine.
I can see that if the locking pawl was a tight fit in the plate then there is a danger of it jamming when things flex.
Has anybody an idea what might be the normal play measured say at the wheel axle?
Wings
Same thing really. I have one tight and one one "loose" wing lock. Basically on the "loose" wing there is a small amount of fore/aft movement on the wing tip (maybe 1-2mm). It seems to come down to the tolerance of the drag pin (The main pins were replaced some time ago). I can't see any visible wear or even measure any.
Any ideas what might be normal/acceptable?
I might just change the pins from left to right, or get new ones made.
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Posted by Jorgen on Tuesday, February 21, 2012 @ 02:50 PM:
Hi Martin,
I agree, to me that sounds like wear in the fittings, both regarding the main gear and the wingfolding mechanism. My 5b is dismantled now, but what I can recall there was not much play at the wingtip when locked. There could have been a millimeter though. I assume it would be possible to get new pins, possibly get them made with the old ones as templates. But I fear the wear might be on the "female" side, maybe it's possible to bush them?
A less likely possibility but an excellent post: "The phantom klunk" by Bob Grimstead:
http://sbeaver.com/cgi-bin/fournier/cutecast.pl?session=4SVVT1hDrAuZZYwtYF1KwE0GhJ&forum=11&thread=490
May the 4's be with you/ Jörgen
Posted by eugenio on Tuesday, February 21, 2012 @ 03:35 PM:
For the wing you should do an oversize bolt and pin and ream the holes to fit. You cannot bushing the holes, you haven't enough material all around. The problem usually is the ovalized hole, so a 1/10 or 2/10 (mm) ream will fix the problem.
For the undercarriage, if it's not the aluminium to be worn, it's the locking fork. There should be some play, but just enough to let the fork's pin engage the two aluminium half moon.
All drawings for the hardware are available for the CFI Members from the CFI France in Pdf format.
Eugenio
Posted by Martin Hill on Sunday, February 26, 2012 @ 12:24 PM:
Thanks guys, but you didn't really answer the question of how much play is acceptable or normal.
Eugenio - thanks I will ask Michel if he has the drawings for the undercarriage. It will be a useful reference from which I can see how it should be. Since I know my undercarriage was refusrbished I am wondering if the aluminium half-moons were poorly remadeor the slots altered.
For the wing the play results from the rear wing bolt (511 006). It is solid in the fitting and shows no wear. Maybe the hole in the outer wing fitting (501 009) is slightly oval. But as I said I can't measure or see it.
I guess the answer is to get/make an oversize bolt and ream the holes to suit.
For anyone else - Ken Ballington had an amount of RF spares which were bought up by a Mark Bodger (one of which is oversized rear wing pins). I met Mark last year and have his details so will try to liberate some of his stock - or at least find out what has happened to it.
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