Any alternatives to Kawi driveshaft dampner?

[Desk_jockey]

I need another option. I'm running an ET 967 coupled to a Torrent 148 using an ADA billet couplet set that uses kawi dampners. I'm using an oem kawi dampner that seemed to be in good shape but has shown a ton of wear in only 6 hours, allowing a bunch of movement from coupler to coupler. I either need to find a dampner with firmer rubber or need to switch styles to something more durable. This is the coupler I am running. Any ideas?

 

[Big Kahuna]

I would just get a new Kawi dampner and try it.

 

[Jr.]

Poor alignment! Those dampers should last a long time!
Fyi, ADA and most aftermarket Kawi style couplers for Yamaha applications use a much tighter tolerance than the OEM yamaha three finger, thus the alignment needs to be spot on. When you preform your alignment,
The Damper needs to be removed, so you see what shims need to go under each mount. Mark all locations, then realign with damper in place. This is the only way to not have false readings due to damper stress.

Lots of good threads on here over the years on proper alignment technique!

Ski ya, Paul

 

[Rushford_Ripper]

Align pump for midshaft first then midshaft and motor as @Jr. said.

 

[Desk_jockey]

I am not saying alignment is not the issue because something could have moved, but I used calipers to align the couplers and it was spot on side to side and top to bottom. Even the wear on the dampener is uniform across its horizontal surface. I am hoping I just have an old dampener but since I have to take it all apart to replace, I will check alignment first then after replacing and see.

No one makes a firmer dampener?

 

[MTRHEAD]

When we raced mod SXR 800’s we used the large Kawasaki damper. It’s like almost 50% bigger. Since it’s Yamaha threads your in need of look at the old GPR1200 adapters. Those skis made 250hp in pro level race trim. I’m guessing between all the GP and GPR different sizes you could find something. The new breed of pro boats 400-500hp use that same damper for at least the Kawasaki one
I may have one at home I can take a picture of later for size comparison

 

[MTRHEAD]

Actually I just notice ada sells the large Kawasaki couplers. Maybe they make or would make the Yamaha couplers with this large coupler.

 

[john zigler]

I agree with Jr, your alignment is off....

 

[TheBuzzard]

in all the years I been ripping kawis apart, I've came across 2 dampers other than black rubber ones.
one was blue and the other was a clear yellowish. I melted the blue one heating a coupler and using the coupler tool and they are both floating around here somewhere.
they are a harder more durable material than rubber. somebody told me those kind make for a lot of vibration.
I always just use good used rubber ones , since I have a bazillion of those.

No one makes a firmer dampener?

 

[Storbeck]

I'm wondering what you mean about using calipers to align. I can't think if anything you'd do with alignment that would involve calipers.

 

[Desk_jockey]

I measured the gap between the hull side coupler to the engine side coupler. I did this on the left side and the right and compared the numbers then again on the bottom and on the top. It was all spot on after shimming slightly this way and that. I did this with the rubber out. In my hull there is a ton of room to work with so I guess I am lucky in that regard. I guess I could have used feeler gauges also.

 

[Big Kahuna]

What about vertical differences, did you check this? Did you do this with the dampener in there?

 

[Desk_jockey]

A straight edge layed across the top was how I checked the vertical. It rested on both sides of the coupler flat. I am not sure how to do it any other way. I did not check it after adding the dampener. I plan on double checking it tonight since I have not taken anything apart yet.

 

[Storbeck]

You must have WAY more room than any hull I've worked on lol. Sounds like you're pretty confident in the alignment though, assuming you put the save attention to detail in the vertical/horizontal directions.

 

[Big Kahuna]

ok

A straight edge layed across the top was how I checked the vertical. It rested on both sides of the coupler flat. I am not sure how to do it any other way. I did not check it after adding the dampener. I plan on double checking it tonight since I have not taken anything apart yet.

if you did not have dampener then you should should be good, never do it with it installed.

 

[Desk_jockey]

There is a ton of room in there. I will remeasure everything tonight and grab a bunch of pics. Its a PITA to get my pipe out so I have been dreading pulling the engine to replace this.

 

[Big Kahuna]

You must have WAY more room than any hull I've worked on lol. Sounds like you're pretty confident in the alignment though, assuming you put the save attention to detail in the vertical/horizontal directions.

I use to have a brass sliding caliper set that I cut short, it worked in a SJ.

 

[augustaf]

Might the op- by any chance- have too much clearance between the midshaft half and the engine half of the coupler assy? That could chew up/ spit out even the best of dampners…..

 

[Rushford_Ripper]

Might the op- by any chance- have too much clearance between the midshaft half and the engine half of the coupler assy? That could chew up/ spit out even the best of dampners…..

Agreed, are they the correct length couplers? Maybe some pictures would help?

 

[Desk_jockey]

I'm gonna measure everything tonight and get some pics for tomorrow.