Robertson STOL kit drawings

[B2C2]

I have a problem where the flap indicator is out of calibration on my Robertson equipped 1969 T337D. The flaps are moving through the correct deflection, but the indicator shows 2/3 when they are full down at 25 degrees. Other than the calibration issue, the Robertson system is operating as expected. I suspect that the flap indicator cable connection in the wing is out of adjustment based on the maintenance manual that I have which refers to making a mechanical adjustment at the bellcrank in the wing or at the flap lever in the cockpit for the cable. I called Sierra industries and apparently there is no installation manual for this, just a set of 4 foot by 12 foot drawings, that cost $650 for the set. I have the operating manual and maintenence manual but these don't have any parts lists or show the detailed installation. Does anyone have a set of these drawings and could take a picture of the portion that shows the details for the flap indicator cable interconnection point in the wing? Alternatively has anyone had a similar problem and found a different solution?

Thanks

[hharney]

Has someone re-rigged the flaps recently, per the service manual? I have seen where service has been performed on the system and the rigging is not completed correctly. Setting up the indicator on the panel is really tricky and can be difficult at best. If the flap cable were changed or cables released for flap panel removal this could be the reason.

Go to the SM and follow the very tedious sequence of adjustments and rigging. It can take a good day or two to get it right. Checking the degree of deflection at each setting is a good place to start to determine if it is out of rig.

[B2C2]

I purchased the airplane last year, and the behavior has been that way since I bought it. It may have been adjusted at some point prior to that but I cant find an entry for it in the log books. I have checked the behavior of the flaps and ailerons for the correct deflection behaviors in the maintenance manual and that is all working. In referring to the service manual, I think the relevant entry is on page 7-15, item 10, where it discusses connecting the followup control (19) to the bellcrank (21) adjusting the clevis attach point at the bellcrank and the rod end in the instrument panel to obtain full pointer travel. I guess I have been assuming that there is some modification to the standard cessna parts in this area for the Robertson kit, but it sounds like that's not true and standard procedures and the published cessna manual should be sufficient to get to the root of the problem. I have added calibration markers to the flap indicator on the panel for 1/3 2/3 and full, so its more of a nuisance at this point but I would like to get it fixed. I will probably wait for the annual to do it, but wanted to have at least a working theory as to why its doing this to cut down on the troubleshooting time.