Re: NLG Replacement Rubber
Posted: Mon Nov 26, 2018 6:56 pm
Copy - I'll be checking prop clearance as a criteria based measurement though I don't think my hangar floor is level to a .1" tolerance. If your nose is sagging it probably means the pucks are not really compressed anymore - maybe hard as rocks. When I changed out my pucks, the stack on new pucks was at least one puck taller than the stack of old pucks - that was how much elasticity was lost.
Per replacing the pucks, I can't remember the cost of the pucks from Diamond, not cheap I am sure. A manufacture source would be nice. Per the install time, maybe two hours for someone that has run that rabbit trail before - with owner hands assisting. It was a half-day job as I recall but my A&P was a flying friend that did not punch a clock and we took our time to look over everything and followed the AMM exactly. I remember the bolt holding the NLG pivot pin in place being awkward and a slow wrench turning effort. Also, I remember a couple of small rivets to replace.
NLG puck replacement is time and money well spent - I spot landed with a slow stall horn squawking approach speed once a while back where I let my AOA get way too high. The tail skid touched with the mains and the aircraft sprang back forward onto the NLG. That is when you really want your NLG pucks to perform. I have since declared spot landing challenges off limits - too much focus on the spot and not enough on a smooth landing...
One final recommendation - closely inspect the two sealed bearings in the NLG hub. Turn them slowly and feel for any "grittiness" when they rotate. They also take the force of any NLG-heavy landing. The bearings Diamond sells were from a manufacture that sells $10 (cheap) bearings (marked up by Diamond). When I replaced those bearings I reinstalled a $30 German-engineered variety - sold to me by a bearing expert on what bearings to actually purchase. Now smooth as silk...
Per replacing the pucks, I can't remember the cost of the pucks from Diamond, not cheap I am sure. A manufacture source would be nice. Per the install time, maybe two hours for someone that has run that rabbit trail before - with owner hands assisting. It was a half-day job as I recall but my A&P was a flying friend that did not punch a clock and we took our time to look over everything and followed the AMM exactly. I remember the bolt holding the NLG pivot pin in place being awkward and a slow wrench turning effort. Also, I remember a couple of small rivets to replace.
NLG puck replacement is time and money well spent - I spot landed with a slow stall horn squawking approach speed once a while back where I let my AOA get way too high. The tail skid touched with the mains and the aircraft sprang back forward onto the NLG. That is when you really want your NLG pucks to perform. I have since declared spot landing challenges off limits - too much focus on the spot and not enough on a smooth landing...
One final recommendation - closely inspect the two sealed bearings in the NLG hub. Turn them slowly and feel for any "grittiness" when they rotate. They also take the force of any NLG-heavy landing. The bearings Diamond sells were from a manufacture that sells $10 (cheap) bearings (marked up by Diamond). When I replaced those bearings I reinstalled a $30 German-engineered variety - sold to me by a bearing expert on what bearings to actually purchase. Now smooth as silk...