Hobie Cat Forums

It is currently Wed Sep 17, 2014 10:43 pm

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 10 posts ] 
Author Message
PostPosted: Sun Nov 11, 2012 9:39 pm 
Offline
Site Rank - Captain

Joined: Sat Nov 04, 2006 12:03 pm
Posts: 52
Location: Tucson, Arizona
The last time I went sailing the starboard rudder wouldn't lock down because the cam is over rotating. I checked the slider that sets rudder rake in the tiller arm and it hasn't slipped out of position. I tried taking it apart and resetting the cam. The rudder locked down but when it came up the cam over-rotated again.

The port rudder doesn't have this problem. The difference between the two is that the port rudder has the stock spring plunger and the other has a H16 plunger. Until recently I haven't had any trouble with the rudders. Will replacing the H16 plunger with the stock plunger fix this? Thanks,

Abraham

Image

Image


Top
 Profile  
 
PostPosted: Mon Nov 12, 2012 4:31 am 
Offline
Site Rank - Old Salt

Joined: Mon May 09, 2005 10:25 am
Posts: 2568
Location: Jersey Shore
Quote:
Will replacing the H16 plunger with the stock plunger fix this?


Would certainly seem like a logical starting point. I'd also replace the cam.

sm


Top
 Profile  
 
PostPosted: Mon Nov 12, 2012 9:21 pm 
Offline
Site Rank - Captain

Joined: Sat Nov 04, 2006 12:03 pm
Posts: 52
Location: Tucson, Arizona
Quote:
I'd also replace the cam.


The cam looks good.

Is it the same as the H16 cam?

The plungers aren't that different. The H20 plunger has flat sides. The H16 plunger is hemispherical.

I'd like get people's thoughts on what is causing the cam to over rotate.

Thanks,


Top
 Profile  
 
PostPosted: Tue Nov 13, 2012 4:38 am 
Offline
Site Rank - Old Salt

Joined: Mon May 09, 2005 10:25 am
Posts: 2568
Location: Jersey Shore
The catalog lists different parts for the H14/16 vs. H17/18/20 cams, so I assume they're different. Anyway, if you're having issues, the first thing I would do would be to put in the correct parts. They may look similar, but sometimes small variations will make a big difference in the operation of mechanical parts, so best to start with fixing what you know is "wrong".

As for what else could be causing the over-rotation. From your pic, it looks like the cam is over-rotating in the "up" position. Is that correct (sorry, I don't have a rudder handy to recreate what you've got going on)? It looks like you should be able to rotate it back by hand. I'd check for worn out components, and any excess play in the cam (oversized pin hole). Also, if the spring tension is too light, it will allow the cam to push past the detent in the cam and over-rotate.

sm


Top
 Profile  
 
PostPosted: Tue Nov 13, 2012 5:26 pm 
Offline
Site Admin

Joined: Tue May 27, 2003 12:44 pm
Posts: 9019
Location: Oceanside, California
The H 17/18 castings use a square shaft for the (square/rectangle) plunger to run up and down. The H 14/16 casting and plunger are round. They are not compatible I wouldn't think, so replacing the plunger with the correct fitting one will be your first step. If the cam has been replaced or the casting is worn or deformed at the point the cam exits the casting... it might rise up too high and be able to rotate out of the casting under the cam. Another issue is lubrication. You have to properly lubricate the plunger to cam surfaces.

New cam held with the factory pressed-in pin... new plunger.

_________________
Matt Miller
Director of Parts and Accessory Sales
Hobie Cat USA


Top
 Profile  
 
PostPosted: Wed Nov 14, 2012 8:49 pm 
Offline
Site Rank - Captain

Joined: Sat Nov 04, 2006 12:03 pm
Posts: 52
Location: Tucson, Arizona
I'll replace the plunger with a H20 plunger.

I've been using the H16 plunger for a number of years. It puzzled me that it just recently stopped working.

I always try and put a small amount of lithium grease on the cams and plungers before a sailing trip. I learned that the hard way. When I was new to the boat I broke a bunch of rudder cams before an acquaintance suggested some lithium grease. A note to that effect in the assembly manual would've been helpful. I don't ever remember having to put grease on H16 cams. That's how I got the H16 plunger. I broke yet again, another cam at a regatta and the same acquaintance gave me a H16 plunger. I put it in and forgot about it until now.

What's the story with the factory pressed in pin for the cam? I recently replace the pin in the cam that over rotated. When I was messing with it I noticed that the old one had stripped. Should I send the casting in to get a factory pin for the cam? Thanks,


Top
 Profile  
 
PostPosted: Thu Nov 15, 2012 4:04 pm 
Offline
Site Admin

Joined: Tue May 27, 2003 12:44 pm
Posts: 9019
Location: Oceanside, California
The pins are flared on both ends when installed. They don't have to be installed by the factory... just are the factory original part instead of the threaded (sister) screw type. Those are loose, wallow out the hole and can allow the cam to move vertically away from the plunger which could cause the plunger issue you experienced.

_________________
Matt Miller
Director of Parts and Accessory Sales
Hobie Cat USA


Top
 Profile  
 
PostPosted: Tue Nov 20, 2012 11:01 pm 
Offline
Site Rank - Captain

Joined: Thu Apr 19, 2012 12:15 am
Posts: 88
Location: Kaneohe, Hawaii
the problem is quite obvious from studying your pictures.
Lincoln, on your lucky penny hasn't learned to text you that there is a problem. He's looking right at the darn thing.

Actually Matt sounds right on. The only thing I could add is possibly add spring pressure with your adjustment screw so the plunger is tighter on the cam.
Does your rudder kick up when under load (like on a screaming reach)?
Or, is your tiller hard to pull up when raising your rudders?
This would be the spring pressure needing adjustment.

Lastly I sail in salt water and never grease my cam. it washes off when I rinse the boat down so why bother. Cams are more of a tell tail when something else is worn out like the hole oblonging in the rudder. That will screw up a cam fast.


Top
 Profile  
 
PostPosted: Sat Nov 24, 2012 9:11 pm 
Offline
Site Rank - Captain

Joined: Sat Nov 04, 2006 12:03 pm
Posts: 52
Location: Tucson, Arizona
I did try to back out the screw that tensions the cam spring. It's frozen.

The tiller has always been easy to lift. Lifting it on the water, to clear sea weed for example, would invariable break a cam. Greasing the cams fixed that though.

I've never had any trouble with the rudders kicking up under sail. My Dad and I are big. Both of us are ~380lbs. When were both out on the wire the boat is moving. The dagger boards will hum as the boat surges with gusts? I tried wet sanding them and putting on a couple of coats of hull polish. I can't tell if it helped. I digress but why is the shape of the dagger boards different from the rudders? I'd expect the dagger boards to have an elliptical outline like the rudders.


Top
 Profile  
 
PostPosted: Sun Nov 25, 2012 5:29 am 
Offline
Hobie Approved Guru

Joined: Mon Jul 14, 2003 7:11 pm
Posts: 4611
Location: Detroit, MI
Abraham Jones wrote:
[W]hy is the shape of the dagger boards different from the rudders? I'd expect the dagger boards to have an elliptical outline like the rudders.
Probably the biggest reason is practical - when the boards are fully up, an elliptical board isn't stable in the trunk.

Boards with squared off ends are also much easier to make and less prone to damage.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 10 posts ] 

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 0 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group