tiller arm slipping out of rudder cam

I have a '79 H!6 with the "old style" tiller arms ; that is the arms have the pin the fits into the cam rather than the adjustable plate. I have replaced cams, plungers, springs, and delrin screws. The cams are well lubricated and move easily from up to down position.

My issue is that the pin on the tiller arm that is supposed to stay engaged with the "hook" part of the cam does not do so. The tiller pin will not stay engaged with the cam hook and the tiller will ride on top of the cam. Of course when this happens the rudders are not locked in place and will rotate up while sailing.

I suppose the newer style tiller arms with the adjustable plate will solve this problems by keepoing the tiller arm locked into the proper position (on the hook of cam). Is there anything short of buying the newer style tiller arms that will help me out?

Thanks.

Mitch

Fill / redrill the upper hole in your rudders.