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Sundstrand buffer spring adjustment

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This spring I swapped in a Sundstrand hydro from a 7016H to my 3416 and now I have a fine adjustment question. First off, I have the manuals and see all the adjustments but my question is strictly towards a piece that I don’t see much adjustment to, the buffer spring on the engagement rod. Originally it had one washer on either end of the spring, but it didn’t seem that the spring would re-center after the input operation. Example, if moving the hydro lever into reverse the spring would compress to take some of the jerkiness out of the input motion and then decompress so that the roller mechanism would be at the far end of the track in the cam. However, when going forward the spring will compress and not decompress so the roller never reaches the end of the track in the cam. What seems to have worked is the addition of washers to that spring, but obviously this eliminates the buffering action and the input is now jerky. In writing this out it seems the spring is weak, but before I go down that road, is this something that the other adjustments have any role in?FWIW neutral seems to be correct, it just needs overcorrection if wanting a full stop after reversing. If desiring a full stop while going forward it works perfect.Here are some pictures for reference;


The spring and three (on each side) washers.


The cam at full reverse.


The cam at full forward.


The cam after manually decompressing the spring.


The cam at neutral.






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Looking at the pictures you need lube at all connections. Remove the washers lube the spring box the pivots on the cam and the roller in the cam.

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