|
|
|
|
Dave's RV-7A Builder's Log
|
Date: 12-6-2014
|
Number of Hours: 4.00
|
Manual Reference:
|
Brief Description: Misc engine work
|
|
Marathon session at the hangar today. My next project was to figure out the throttle and mixture cable brackets and get those installed. The Van’s firewall forward kit has a sub-kit that contains all of the various parts necessary for attaching those brackets. Well, almost all of the parts…
After studying the drawing and looking over the parts, I started with the mixture brackets. The aft bracket attaches along the top left side of the oil sump, using two of the case bolts. When the engine shipped, there was already a hose held there by an Adel clamp, so I removed that and put the bracket on. As an aside, I remain a bit confused on the guidance for torquing and securing various nuts, screws and fittings forward of the firewall. Most of what I’ve read says no aluminum or Nylock nuts on the engine, but Lycoming makes generous use of those on my engine. I suppose if it’s good enough for the engine manufacturer, it should be ok. Anyway, the sump case bolts are secured with lock washers and nuts, so that’s what went back in place for this bracket.
The forward bracket took a little more time and study as it involves a bellcrank that controls the mixture setting on the throttle body. The pictures show the assembly much better than I can describe, and while there is still quite a bit of adjustment left to do, the basic fitting is complete. Back to the comment about the parts in the sub-kit…the two bolts securing the bracket are standard AN4 bolts—different than the case bolts with respect to threads. These particular bolts are secured with all-metal lock nuts, rather than the lock washers on the other bolts, and no matter how hard I looked, there was only one in the kit. I wonder what shipping will cost for a 39 cent nut?
After finishing the mixture cable brackets, I got out the safety wire and spent about 30 minutes and at least three attempts at getting a satisfactory job on the throttle bracket. The final result is shown in the last picture--looks ok to me.
|
|
Forward mixture cable bracket and bellcrank, complete with missing nut
|
|
Aft mixture cable bracket
|
|
Throttle bracket
|
|
|
|
|
|
|
|
|
Copyright © 2001-2024 Matronics. All Rights Reserved.
|
