How do I reduce the gap between the midshaft and the Engine coupler

[madoyster]

I went and did a weekly check on the ski, Loose bolts, chit falling of stuff like that. I noticed that there is a gap of about 10mm between the midshaft coupler and the engine side coupler. What can I do to reduce the gap between the two. The engine has been moved as far forward as the motor mounts will allow. What's going on here? It's almost like my midshaft is shrinking (maybe my ski dosn't like cold water, we all know about cold water and shrinkage lol)
Anyone Ideas, I can deal with the cold water shrinkage but don't let my poor ski suffer anymore.
Thanks Y'all
M

 

[sflsurfrider]

if your engine is moved as fwd as itll go, you can move the engine back to reduce the gap.

your other option is to remove the midshaft housing and pound the midshaft fwd with a rubber mallet.

 

[SuperJETT]

Like SFL said, plus the spec is for the midshaft to stick out the back of the housing 20mm.

 

[RMBC Freeride]

Sounds like you hit bottom with the tail of your ski in shallow water. The engine slams back and pushes the mid shaft back further into the housing. I've done it a few times, most recenty at the Texas freeride. It sucks!

 

[Mike Serlin]

I've got the same problem, and when my motor revs to high It will vibrate like crazy and blow couplers. I say pound the midshaft housing with a rubber mallet. if you don't have a rev limiter be carefull and make sure your motor is still alligned really well.

 

[RoyalFlush@PCB]

A mallet won't always work. In that case, or if you want to make the job easier, you can use a hydraulic press to get the shaft back in the right spot.

 

[madoyster]

Sounds like you hit bottom with the tail of your ski in shallow water. The engine slams back and pushes the mid shaft back further into the housing. I've done it a few times, most recenty at the Texas freeride. It sucks!

Dude that's exactly where it happened to me. I recall hitting so hard it moved the tank, battery and hood back. I should have checked.
The shaft was pulled and moved quite easily after the fourth or fith hit, I'm glad I pulled it because it didn't look that well lubricated back there I pumped grease in there a few weeks ago but failed to use marine grease. This is all removed now and my baby is full of the good stuff.
Thanks guys I'll lake test her today.
M

 

[wildman326]

So, if your gap is too big that will cause it to vibrate like a mofo? I broke 2 motormounts the other day and thought it was the motormounts that were causing the vibration. However after fixing them it's not much better.

Should stick out 20mm? And approximately how much distance between the front and rear couplers? About 1/4 inch?

I've got a press, so this is no biggie. I'm going to check it out.

 

[keefer]

The Yamaha manual for the SJ says 2-4mm gap for the couplers. I think mine are more like 5mm or so. I know that with my engine at 210 comp, it vibrates quite a bit but no damage to the coupler. I am running the old rubbery stock motor mounts so that just makes the vibration worse. I need to upgrade to a set of Monkey Grip motor mounts. Get that gap adjusted and update the motor mounts, that should reduce the problem.

 

[madoyster]

Well Guys just got back from the Lake everything is looking good. I now have about a 3mm gap with no vibration. The true test will come when we hit Lanier next week. Thanks everyone. (It's my trademark:Banane01: )

M