The Messer Log

[Messer]

ADVICE / ASSESSMENT needed....   
  She is in the water (pic attached)... Anyway, first outing, kneeboarding and wakeboarding for the teenagers.  Kerklunk!      A damn tree in the water, couldn't see it with the sun like it was. Vibration at a notch ahead. Felt like bad cavitation when I tried to get up to 12-15 knots, so I backed her down. Pulled her out of the water, prop looks ok, minor fin dings at extremety. I grabbed the prop and there is some play as I work it in both directions. How much play- about a millimeter or so each way (read- the shaft does not move with it in the play). The last time I grabbed the prop I think she was tight.
  Anyway, I'm thinking I sheered the key in the prop. Anyone else had similar situations.  I'm gonna order a prop puller and do it myself, heck surely I can't screw it up anymore!

[backfoot100]

That sucks. Hopefully you weren't going that fast when you hit it. Any time you hit something, it could be as simple as a rebuilding the prop or difficult like removing a strut that has been bent.

Could be a sheared pin but I would think that would be the last thing to go after a stike of something. It could also just be play in the tranny moving it back and forth as you describe.

Even though  the prop itself might look OK  the slightest ding can make them vibrate bad. I've seen props that practically had a blade sheared off that ran perfectly smooth (albeit much slower) and then another that had the slightest little ding on an edge shake the boat apart at idle. They can be really finicky at times.

You could have also bent the prop shaft. The slightest bend can shake a boat apart too. Ideally a dial indicator is the cats nuts for this. It'll pick up a bend that you'll never see with the naked eye. If it's bent that you can see it with the naked eye, you have to pull it and a good prop shop should be able to straighten it.

You might have bent a strut too. A bent strut you'll never see with the naked eye but it'll mess up your alignment big time which could cause vibration. You can undo the coupler at the tranny and verify if your alignment is still good. If it is, I gotta believe the strut is OK and you just need to verify the shaft isn't bent just aft of the strut and get your prop rebuilt and you're good to go.

Either way, you can't do much of anything until you get the prop off so a puller is a good place to start.

Another thing. If it's going to be clearly an expensive fix i.e. a bent shaft and/or strut and resultant alignment issues check with your insurance company. Any good boat insurance covers underwater strikes. Many years ago I hit a rock bed on a lake that I thought I knew like the back of hand. I was idling at the time and not only did my prop shaft bend at a 45 degree angle right after the strut, it tore a blade off the prop. I ended up calling my insurance company and they covered the $900 repair bill completely. Definitely something to think about if you aren't aware of it. That's why we have insurance.

[Messer]

Thanks Backfoot...taking it all in. Up all night on the boards reading this stuff. I'm gonna get a dial indicator in the next day or so. There was a nice video on another site on shaft alignment. I think if I watch it a few more times I'll start understanding it, ha.

In the meantime- I ripped out the floor and no obvious issues under or above. Pulled the prop (pin out- easy, nut off with block of wood- easy, prop pulled-easy with only slight tightness-was able to pull with hands and using no puller or hammer)

The key looked a little too far forward but it was tight by hand, unable to remove it but I could slide it around by hand.

POSSIBLE PROBLEM - I got in the boat, grabbed the coulpler off the tranny and grabbed the shaft. I was able to move one about 1/8inch or more while holding the other steady. It may have even slipped astern a bit. That seemes to me the reason I felt like a "cavitation" effect. Check out the video and pix and let me know what you think.

If the shaft to coupler is the problem then whats the fix? I watched the how to's and if I'm not mistaken, I need to remove the coupler from the shaft, put it in an oven and get it smoking hot, remove it(with gloves), put it back on the shaft as soon as possible and when it cools it should shrink to a tight fit. So my question, can the coupler be placed crooked or is it precision enough that there can be no play? Also, once I have it on, should I bolt up the shaft and coupler to the tranny before it gets cool?

video of movement -
http://youtu.be/n3yFqomzRf8







 

[backfoot100]

Hey Mess,
I'm blocked from watching the vids here at work so I'll have to wait until tonight.

If you any free play between the propshaft and coupler, you have issues my friend. If it's as loose as you say, something is very wrong. I would remove it and see what's going on.

You can remove the coupler by getting some longer bolts the same size as the ones that bolt the two coupler halves together. I would think hardened would be better. Put a socket (just a little smaller than the shaft diameter) in the center of the shaft between the two coupler halves and put the longer bolts and nuts on the coupler halves just like you would to bolt them together normally. Start to tighten the bolts evenly around the circumfirence of the shaft (and socket) and it wshould push the shaft right out of the coupler. I have heard of some of them being so tight the coupler can actually start to bend a bit. If it gets really tight, you may have to heat up the coupler half on the shaft a little bit but it should come out.

Your replacement method is correct but you don't have to bolt everything together while it's still hot. Just need to get the coupler on the shaft and wait for it to cool down. Some people even take the shaft itself and put that in a freezer and then put the heated coupler on the frozen shaft. The coupler face may have to be turned to ensure that it is true before installation or sanded down on a flat surface.

Ron and/or Dan may have to interject here as to the fix if there is free play now between the shaft and coupler. The shaft may have spun, broke or sheared somehow. The coupler may be spun out of round somewhat and is shot. I really don't know without actually seeing it. All I know is that they should not be loose in any way. You may need a new shaft or new coupler or both when you finally get it apart and see what the problem is.
My gut feeling is if you have any play now what so ever, the shaft and coupler are done. I just can't imagine that one of them would be able to be reused reliably but I've never experienced anything like what you're describing.

Hopefully the guru's can help out more than me. They damn sure know more than I do.

[Messer]

orig post - in maintenance
http://www.amskierboats.com/forum/index.php/topic,117.0.html

Ron / guys,
  I know this thread has been quite for a while so I'll post the link in MESSER LOG as well where I'm at.
Question-
1. With a straight cut shaft, which I think I have, once the couping is off can the shaft be completely removed via the stern? Someone told me I would have to pull the engine..
2. Will the set screws actuall come out with penetrating oil or do I need to go find a torch?

[IndyDyne]

Messer,

1. You do have a straight cut shaft just like I did.  I believe the shaft should be easily removable from the boat.  However, I did not remove mine so I am not much help here. 

2. My set screws came out with PB blaster.  They were toast after removal as the heads had begun to spin.  I replaced them with stainless and all was well.  From the looks of your video, you may get by with taking everything apart and replacing with new bolts as long as your shaft/coupler is not too worn.

Good luck.

[Messer]

I hope so. The way it feels is as if the set screws took a beating (one hit) and it may be simple fix. I just saturated the set screws in Wd40 penetrating fluid, fingers crossed.

[RonT]

You have a worn shaft end/coupler, it is a straight cut shaft, not a tapered shaft. The wear will be within the shaft key, keyway in both the shaft & coupler. By the play indicated it is past its useful life & needs to be replaced preferably with a tapered shaft/coupler. Cause is from too many hours running out of alignment...something has to give.
Removal: It either has to go out the back -or- front, choice is yours, I generally go out the back & service the rudder/port at the same time. Drop the rudder, remove the coupling, slide out the back, re-pack the shaft log while out of the boat. In my shop if the shaft is really messed up & the key is twisted inside i use my sawzall to cut the shaft. (In my shop, it's one thing for a customer to have to pay for a shaft & coupling but I can't expect to charge them hours to remove a worn out coupler, so if I remove the coupler bolts & I can't release the coupling with a few minutes, it gets cut off)
This is also the time to check & replace the strut bearing.
Call if you get stuck.
RonT

[Messer]

Thanks Ron! After scouring the boards I had a feeling the alignment was off. Once I puled the four bolts from the tranny the shaft coupler dropped about 1/2inch. I refitted it to stabilize while trying to get the set screws out and I had to pull the shaft coupler up to align the holes. I'm heading to the basement as we speak to get back on it.

[Messer]

Ron,
  While we are all at work...
-would my current condition cause the feeling of cavitation or general rumbling when I throttle up? (this after just hitting a submerged tree combined with probable fretting over years of mis-alignment)? I didn't run it up again, went sraigh to the trailer...

-My Skier is a 1984, will the two peice strut bearing you have work on mine?

Parts list so far-
1. new shaft and coupler 1”
2. strut bearing
3. shaft log hose
4. stuffing box cotter pin
5. shaft packing (Teflon)

[RonT]

Probably has the 2 pc. in it already, measure the length of the barrel, if it's around 6" long, its a 2 pc. , I haven't seen a 4" long strut barrel in a long time. Another suspect part when you have your situation is a worn or broken drive plate damper, located inside the bellhousing attached to the flywheel. 100% of your HP must transmit through the small springs in the plate to the trans input shaft. They typically make a strange klunking noise at low rpm before they go out completely. 

[Messer]

I only post my heartaches so Joel can get a laugh and everyone else that may come into a similar problem can see what to expect or hopefully learn from my mistakes.

Anxious to get her back in the water beforethis upcoming big weekend I decided to remove the coupler, hope for the shaft to be good, and find another coupler fast.

Reality- set screws in coupler not budging. After about $100 worth of bits (cobalt, titanium and who knows what), penetrating oil...sledgehammer, no dice. Not to mention about 10hrs of time.

Reverted back to Ron's recommendation (since he told me what would happen and I'm hard headed sometimes), ordered shaft and coupling, strur bearing, packing... and some decals of course.

10 hrs drilling, no set screws out. 25min with new Sawzall- shaft cut, shaft box out, rudder out, coupling off (slung it as far as I could, guess I should go get it out of my neighbors yard)...  A few pix and then a few questions on next post.

[Messer]

1. What adhesive do you recommend for the SHAFT LOG HOSE? There was a black rubbery product on there.

2. The rudder came off easily (so did my prop actually) with no need for press/pull tools. It seems that water would intrude via the rudder shaft but I didn't get any kind of packing out of it. Is there any? If so, what kind?

[backfoot100]

I believe that you need to unscrew that big nut on the rudder packing gland to get to the shaft packing. All you need is standard shaft packing rope but I would suggest graphite impregnated shaft packing rope. It's much more slippery. I'm just not sure about the size. I keep thinking 1/4" but I could be wrong. Mybe Ron or Dan can chime in.

The shaft packing hose should just have a couple hose clamps. At least mine does. One at the base that seals the shaft log and one at the coupler end that seals the packing gland. Then you use the same packing rope for the rudder unless your's is a different size. I don't beleive it is. Ron or Dan can confirm that too.

[RonT]

Teflon packing (rudder port nut probably has a small set screw in it, look carefully before using a 48" pipe wrench to loosen)
no sealant on hoses