R21 Steering Arm Question Urgent - sheared bolt

Joined
Aug 4, 2009
Messages
19
Fluid Motion Model
C-24 C (Sterndrive)
Hull Identification Number
fmlr2105B505
Vessel Name
Maggie
I have an older R21 and need quick advice so I can take my office boating tomorrow! Please see attached photos.
I am looking for some advice on attaching my ‘steering arm’ (the bronze longer piece shown that bolts to the rudder) to the ‘smaller part’ shown. The original bolt sheared off right where it goes into the steering arm. The original bolt was 7/16 wide and smooth where it went into the smaller part, and then went down to @ 3/8 inch and was still smooth were it went into and through the steering arm. The original bolt sheared off right in between the steering arm and the smaller part.
Question – is this bolt meant to rotate smoothly in both the steering arm and the smaller part? Or, am I supposed to tighten it right down? I imagine it should be allowed to move smoothly, but I have to make sure the locking bolt on the top does not come loose.
Note my parts store does not have the original bolt and recommended that I just bore out the steering arm to 7/16 and use a nylon nut and a locking washer. I plan to use Loctite also. One friend recommended using a straight nut and locking washer, as the nylon will eventually break down
Any advice on how to secure the nut / bolt so it will not come loose? Do I need smooth stainless steel washers elsewhere to help insure smooth rotation?
Question - is regular grease fine for this, or do I need lithium grease or something else?
I was quite lucky to have someone else in the boat when the bolt sheared off and I lost all steering. I have to lean over the back and push the rubber in the required direction at a very slow rate of speed.

Apologies for not knowing the names of the parts, and thanks for any assistance.

well, obviously I have not figured out how to attach photos, but I think I have joined the group to allow me to post photos. Maybe later today. I could email the photos too.
 
Nylock nuts are all over boats and even airplanes. A high quality nylock nut isn't going to deteriorate in your life time. Lock washers are much more iffy over the long term. You can also do both if you have enough thread, but the nylock will do the job.
 
My prersonal favorite on rotating fasteners is a castellated nut with a cotter pin. You can get a machine shop to drill a hole in the bolt or you can go onto the internet to Aircraft Spruce company and they will have a full selection of aircraft grade bolts and castellated nuts that will do the job. Of course, I haven't seen the pix yet and am guessing at what the connection is. Is your boat a classic 21 or the EC?
 
Thanks for the comments. I have loaded two photos of the parts in question on my gallery now.
 
It is the classic 21
 
A couple of quick points. Castellated nuts are great for applications which require solid connection, but they are not recommended for moving joints which might catch on anything. Secondly, it's good practice to make sure that there are no threads contacting the moving surface in the bore of the joint. Aircraft bolts are sized so that there is just enough thread to tighten the nut assembly, usually leaving 1-3 threads beyond the nut. Washers are essential.
 
I have added several photos to my album that show the final repairs. They may help others facing the same problem. I may not have needed to cut into the fiberglass to allow easy removal of the rudder handle, but I never found a better way.

Be sure to grease the bolt through your rudder handle on a yearly or biyearly basis, as the result of the sheared bolt was total loss of steering and control and a repair while traveling at sea would be very difficult.
 
I's maybe have run the bolt up from the bottom with the nut on top, precluding the need for cutting a "key hole" in the deck. It looks like it is possible to get the appropriate wrenches to a top mounted nut and replacing that fitting without having to remove the steering arm itself. They way you have it repaired will require the "key hole" to get the top mounted bolt out because of clearances to the bottom of the deck. But I suppose you needed the extra hole to get the factory top mounted bolt out in the first place.

I haven't run into this problem on my 21 classic yet, but I think I'll give it a good inspection in the spring, so thanks for the heads up. Just the kind of info we need on these forums.
 
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