G'day I sailed my new to me 5.7 for the first time last night It's got these Marstrom rudders with cardon stocks that have a tube that clips down but they slop around and pop up. Before I make any alterations can anyone tell me how tight they should fit against the little disc that locks them down? Can anyone tell me how much under they should rake?
regards

More photo's

I set the amount of tension on the adjustments (that pop up the rudders when they hit ground) by locking them down (on the trailer or wheels) and apply pressure with my foot... or hand. Then adjust until the desired amount of pressure is reached (needed to pop them).

I adjust the amount of rake is in relation to my helm conditions (lee or weather helm), mast rake, etc. I always shoot for a neutral feel (with a little weather helm).

the rake looks roughly correct - but you'll have to sail it to see for sure.

Those are Marstrom Tornado Rudders. In general, the lock should be tight enough that there is a solid click when you lock them down. The rudder should fit firmly against the casing.

There are 3 adjustments

The threads on the locking arm where it attaches to the rudder. Remove the guide at the front and twist the arm to adjust the position of the lock. The front of the rudder should be firmly against the casing when it locks down.

Lock tension - The locking discs on the arm attach to a tube and there is a little screw on the tube. The screw adjusts the lock tension. I think this is supposed to be the kickup tension. ( there is a little bit of bungee in the tube that acts like a spring. There are also some little metal discs that fall out when you take it apart. I disassemble mine in a small room with a tile floor.

The Rake - There is no simple rake adjustment. You can shim the rudder casing if you have to. I would adjust the rake parallel to the stern to start with and then rake them forward if the weather helm is objectionable. To me it looks like you have a little more rake than a Tornado. If you have just a little weather helm, leave the rake alone until you know more about the boat.

In general, these rudders don't have much adjustment. Changing the rake is an effort . The threads on the arm and the lock tension really just compensate for wear. They are great rudders but they have some quirks.

They will stall. To unstall (?) them you must move them toward center and let the flow reattach. On a light wind day in smooth water go out and practice. This will come in handy when you stall them trying to miss a pier.

They are not real UV tolerant. I would not leave them out in the sun if you are not sailing. I wax mine with a bees wax compound. It keeps them very smooth and it absorbs UV.

To add some more...you will not have the right Ackerman angle on the tillers for the 5.7...so your tacking may be tough to perform well.

I've found I cannot get sufficient lock down force no matter how much I adjust them...so I put a piece of 1/4" bungee around the lockdown & tiller arm to add a bit of extra force. They will still kick up on big weed impacts so I know it's safe.

I've recently broken the white plastic arm guide (the big one). These are Delrin and will eventually crack. They are "handed"...with the lockdown tube passing through the part at a left or right angle...hole is cut at match. Rather than order new one from Marstrom and wait months, I've made up a new type out of some spare carbon plate & rod I had sitting around. Works a treat and is pretty bullet proof. I'll try to get ya some pics.

BTW, how did you get such a pristine set of rudders? You do know they go for close $2k USD, right? Cherish them...I call them "My P-R-E-C-I-O-U-S"!!! Get or make some decent covers with padding to protect those wonderful blades.

Mike.

eliminate the push rod system and run a line through the front of the rudder up between the pintles, to a small block with a breakaway cleat on the tiller bar. at least that is what I would do...

No! Don't muck up the precious! Having a solid hold down setup is way better than yuo can get with line hold down.
If you've never seen a set of these things in person, you don't know what you're risking...they look & perform beautifully.

Thanks for the handy info guys I'm going to play with that lock tension screw.
Mike the boats basically in the same condition as the rudders its all been looked after and this was the second to last one out of the moulds, I got this one because the last one out of the moulds is already here at Kingston. The previous owner previously had these rudders on his Tornado and only put the rudders on the boat in the water and took them off on the water prior to putting the rollers under the boat and they came with padded covers. The tillers have had work done on them and I assume that was to adjust the Ackerman angle it certainly tacked perfect on Monday night.
I took your info to the shed and found the problem, they were set so they had to go in loose or they wouldn't lift up enough to lock them down or lift them up. I had to bend the little bit of curved stainless steel that locks onto the discs so they met at the right angle. Now it clicks in perfect and stays at the rake in the photo, before they moved back 25mm level with the transom under load and had really tiring helm.
We had the spin up on Monday night, what a blast I cant wait for Saturday
regards