Replacing Damper Plate on a DD SN 2001

Let me preface this thread with a disclaimer that I am in no way a boat mechanic. What you will find below is my opinion and what I have learned through my experience changing out this part on my boat. I only hope that this may help someone, that finds themselves in the same situation, save some cash and better get to know their boat.


A few months back, while wakeboarding the Delta, the Damper Plate went out on my 1987 SN2001. For those of you who don't know what a Damper Plate is (I didn't know until after mine went out), it is a plate that is mounted to the fly wheel of the engine that holds the shaft (spline) of the trany. I believe the purpose of the Damper Plate is to give out when there is excessive strain or torque on the prop so that the fly wheel and trany don't take on damage. When the damper plate went out, my boat was suddenly in neutral - even when I tried to engage the trany. This happened to me when pulling a rider out of the water from a dead stop. I did hear a loud pop when it went. Right away I thought something pretty bad had happened. That night a friend of mine shot me a link to a thread on damper plates (thanks Gordon). It sounded exactly like what had happened to me. The tread was about a guy who replaced the plate himself. He had used a forklift to pull the motor and said it took about 8-10 hrs (it is not that bad, trust me, read on!). I went to my local shop to see how much they would charge and they told me it would be around $1000, maybe more, because they would pull the motor!

To make an already to long story a little shorter, I decided to try and fix it myself and took a few pics. The repair was a lot easier than I thought so I decided I would share my experience. After getting it done, I can't imagine having paid someone over a grand to do this.

First thing I did was remove the engine cover (dog housing) and floor.

Next, I separated the shaft from the trany (only 4 bolts) and carefully slid prop shaft towards the rear of the boat. Be careful when sliding it back, because the prop will hit your rudder.

Next I removed what I needed, to be able to pull the trany and fly wheel housing away from the motor. This was much simpler than it may look or sound. I did not have to drain any fluids or disconnect anything that was complicated to put back. I did however take lots of pics before I pulled anything apart just in case I forgot where something went. I had no problem putting everything back, but I would still recommend taking before pics.

Once I had everything out of the way, I was able to take off the bolts that were on the front side of the housing.

Next I pulled the started. This is only 2 bolts and gives you lots of room to get to the rear bolts that hold the fly wheel housing.



With the housing unbolted from the engine I had to unbolt the rear motor mounts from the trany. IMPORTANT: make sure that you put some sort of blocks under the engine pan because the engine will want to drop when you remove the rear mounts - trust me on this!



(Message edited by centralcali on March 26, 2006)

With everything unbolted, I was then able to pull the trany and fly wheel housing off of the motor. The great thing about this was that the fly wheel housing is completely dry! Again, I didn't have to drain any fluids! If I had to guess, I would say that the trany, with housing, weighed about 50-70lbs.

This is a pic of the Damper Plate after I took it off. You can see where it is broken.

At this point of the repair I only had 2 hrs invested and did not have to get a hoist or crain! I totaly took my time. The 2 hours even includes taking everything out of my boat and a few potty breaks. This was not hard, and I AM NO MASTER MECHANIC, trust me.

Ok, I have to admit that putting the trany back on was a bit of a pain in the a$$. Only because it was a little heavy and was kind of akward to get under and handle. After a few minutes of handling it I decided to lift it with a strap to get a more even lift. I did have to have my wife give me a hand with this part to get the bolts started.

Once I got a few bolts started, it was just a matter of putting everything back together! I ended up having about 4 hrs of time total invested and $100 for the Damper Plate.

IMPORTANT: One thing I didn't mention above, before you unbolt the rear motor mounts you will have to put some sort of block under the engine pan because the motor will want to fall - trust me on this!

The last thing to do was just take it for a test run. Everything went great!

I hope this helps someone. I'm just stoked because not only is my boat finally fixed but I saved a little cash that I will need for gas. It was also fun to learn a little more about my boat.

Trevor, great write up and big props on the DIY! Gotta love old boats. We're doing some repairs to ours this weekend as well.

You should duplicate this thread over on the2001.com. Reason being, WW will archive this thread and the link will be changed making it difficult to find. I'm sure it could help many SN2001 owners in the future.

i had trans issues w/ my 87 ski supreme --long story short, i had the trans out 4 times.. needless to say i had it mastered. as trevor has stated and shown, this is a simple procedure... one key factor to remember is to make sure the prop shaft and coupling to trans are true... (properly aligned)... great write up -- should help a few down the road