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View Full Version : Bent shaft, strut, rudder, prop


Bert
08-09-2004, 11:57 AM
We pulled a 2004 X star off the lake the other day. They were dead in the water and said they had found the shallow part of the lake ( that's granite in that lake) and the prop was damaged. The driver had a big bruise on his head from smacking the windscreen frame with the sudden stop when they drove ashore.I felt bad for the guy but geez I looked inside the boat and the floor was covered with empty beer cans. :eek:
Once we got it on his trailer I had a quick look at the running gear. I didn't see any obvious damage to the hull but the shaft and strut were bent about 6 to 8 inches off centre and the rudder was mangled and bent towards the stern. The prop! It looks like it was a 4 blade nibral but all that was left was the hub and about a 1/4 of one blade. He told me his spare prop looked just like that too!!! :confused:
I have heard through the grapevine he has been quoted 12K to repair! Is it possible to cost that much?

bcampbe7
08-09-2004, 12:01 PM
OUCH!!!
Reason #126 why alcohol is not allowed on my boat.

boatless
08-09-2004, 12:08 PM
If he was drunk at the time, I wouldn't help him get the boat to his trailer. I would make a quick call to the local police. I don't care what people said, guys like that should not aloud on the water or the road PERIOD !!!!

Alex.

tall_ andy
08-09-2004, 12:11 PM
12K?? Thats more than I spent on my boat OUCH

I agree with Bcampbe. No Alcohol on the boat

:toast: and :steering: = :cry:

east tx skier
08-09-2004, 12:15 PM
As a person who soberly bent up a prop and shaft (but somehow not the strut), and did a little glass damage in the process, I'll wager that $12K is a little steep for a repair. I squeeked in at just a little under $1K parts and labor.

That said, I didn't have to buy a new prop, just refurbed it. :D

jimmer2880
08-09-2004, 12:18 PM
Boatless - :headbang: I TOTALLY agree!


In MD - if you get busted for DWI in your boat - it goes against your auto-driver's license.

Of course, the problem is that there are about 4 DNR Police people to cover about 180 linear miles of river. Do the math... we don't get to see on very often.

Bert
08-09-2004, 04:04 PM
We have the same DWI rules here and the same problems with lack of enforcement.

Good thing is that boat won't be around for a while :D He actually thought he would have it fixed the next day and head out for vacation.
We all looked at each other and thought "what an idiot" how did he get a boat like that??
Hopefully he learned a lesson, but I doubt it :rolleyes:

bret
08-09-2004, 05:45 PM
Fools and money are easily connected. Anyone can buy a boat with more hp than their car, take it to a lake and go.

A month ago at Damn Site marina, there was a guy who literally launched his boat with his "drive on trailer", came back in because it wouldn't get up to speed.

Prop - $389, shaft/seal $389, strut $89, rudder, $580+, rudder bearing/housing/any fiberglass repair...align the engine...I could see it costing him $1400-2000.

east tx skier
08-09-2004, 05:51 PM
Bret, he did what?

bret
08-09-2004, 05:58 PM
He launched his new Larson, WITH his drive on trailer. The front strap and both back straps were still attached. The guys at the Marina wanted to call him all sorts of things but his wife and kids were with him. But...in all fairness to the guy, you would think that a sales staff, with a first time buyer - no forget that, those guys are all about sales at that dealership, anyway, they should have taken the guy to the lake. The lake is pretty high right now so he probably had to back part of his car or truck down but still, that took some "ump" to get that tongue off with a loaded boat. :uglyhamme

Bert
08-09-2004, 06:10 PM
Wow, just when you think you have seen it all. When I am done skiing for the day I like to watch the going's on at the boat launch ;) I have seen a lot of funny and sad things but not that. Often wondered if a boat could float with a trailer attached. now I know :)

T Scott
08-09-2004, 11:30 PM
Some people have more dollars than "sense".

Ben
08-11-2004, 07:38 AM
$3-4K total. (don't ask why I know).

Above prices are good, although I doubt the whole rudder is bent. The "rudder box" that supports the rudder is probably all that needs replaced. It is much weaker than the rudder, probably intentionally. It is under $100. The big $$ is in the glass work, if anything needs repaired. That is all labor, our bill had approx $200 in materials & $2200 in labor (rough guesses, don't have papers here). Our stump hunting adventure ended up cracking the main lateral stringer between the strut mount & rudder box. Had replaced all mechanical stuff & was ready to go until I saw that, which ended all forward progress for 3 weeks....

Side note learned from observing at boat repair shop. NEVER use a stainless prop nut w/stainless prop shaft. They get stuck. If you see one, throw it very far.....

Dan K
08-11-2004, 08:37 AM
Ben,
sorry to hear about your mishap.
Can you explain about the stainless nut a little further, I thought all prop shafts were stainless as are the nuts.

Ben
08-11-2004, 09:56 AM
Dan et all:
Upon picking the boat up from the shop (took afternoon off to pick it up and ski), I was doing a quick once over. Noticed the cotter wasn't in the shaft by the prop, could only see 2/3 of the hole. Further inspection showed I could slide prop back & forth approx 3/4". At that point I was pretty upset considering they had already taken the boat out for a test drive at my request, to make sure everything was ok before I wasted vacation time...

Between when I noticed no cotter & slid the prop, I got a "It is really tight, that's how I always do it" from our friendly mechanic. He also didn't seem to thing the cotter was required, which is where any bit of remaining trust was lost. At $300+ a prop, I like the redundancy. Then I slid the prop before his very eyes and it all went downhill. I also asked why he used stainless nut (I'd only seen brass). "Came with the shaft".

Basically, the nut had "welded" itself to the shaft and wouldn't go on any further. To remove it, after intense prying, they had to grind/cut it off. This resulted in a new shaft again and new prop nut, not to mention a few little scuffs in my new prop.

I had never heard of this, but my boss treated it as a no brainer, not to use the same grade stainless nuts & bolts. He had run into the same issue in industry a long time ago. Evidently it only takes a small burr on the bolt (shaft) or nut to start a snowball effect digging in the threads as you turn it. Add friction & resulting heat and kiss it all goodbye...

After talking to the MC dealer, they had heard about the same issue & said to just use the brass nut. I was happy with that concept. Nothing live the good 'ol live & learn technique.

Not a materials engineer, but I learned my lesson here.

jimmer2880
08-11-2004, 11:08 AM
Ben - thank you for sharing... I never heard that before & often wondered why my nut was always brass... Glad I found out now instead of accidentally putting a SS on one of these days.

DanC
08-11-2004, 12:07 PM
Ben, you described it pretty well.
I think mechanics/engineers call it galling.
There is no worse feeling in the pit of your stomach than when you are backing out a stainless steel bolt and feel it "weld" tight :eek: as you described.

betsy&david Harrison
08-11-2004, 01:28 PM
This guy doesn't deserve to own a MC! Maybe he should invest in a depth guage when he repairs it. :D

Leroy
08-11-2004, 03:24 PM
There was a joke about that posted on the old web site, can't believe that really happened! When I think about unhitching the tongue...I can't believe it!

While I never wish bad luck on anyone, there are situations I see where I just say "you got there...you figure out how you're getting out".

jimmer2880
08-12-2004, 06:20 AM
I almost always help someone in need.... However - there are rare cases where I have to say "you deserverd what you got - now live with it".

Bert
08-12-2004, 10:02 AM
I usually help any one in trouble. In this case one of the guy's was from Tampa so I should have let him swim :rolleyes: since Tampa Bay put a real damper on the good times here in Calgary this spring :cry:

Ben
08-12-2004, 12:19 PM
No offense has been taken, but after reading this, I want to point out the steps we tried to take (all before putting boat in water) to avoid any "submerged objects". The goal was to use a lake that was closer to the house, less driving = more skiing / riding. THe typical lake we go to is a bit further, but we know it is safe.

1. Talked to neighbor who uses v-drive in the same lake / area all the time to go wakeboarding, and used to fish the lake.
2. While out on bike ride w/wife, asked complete stranger who lives / skis on lake where to / not to pull skiers.
3. Watched other wakeboarders / skiers on same lake on at least 3 different occasions, to see where they were going.
4. Talked to local boat dealer who does test drives on the lake.

Unfortunately all of this wasn't enough, and while riding on the board, I had to watch the back of the boat hop up, all the smiles turn to scared looks and feel the pull stop... To make it worse, when I got back up on the platform, I saw about a 10' section of rope tied to a large stump, probably from a bouy that wasn't tied very well to mark it (3 others were marked about 50 yards away, where we were steering clear of).

Anyway, I guess you can never be too safe in questionable areas, unfortunately a lot of the lakes up here have shallow spots. Oddly enough, we haven't been back to that lake since (except on bikes).

east tx skier
08-12-2004, 12:37 PM
Ben, you're in good company (at least I'd like to think so). I banged up the shaft/prop on my father-in-law's boat pretty good a month ago, and am familiar with the mood-altering vibrations that result from hitting non-liquid things in the water. Got it back to him on Monday and will be skiing behind it this weekend. He got it back better than it was before the accident (washed, waxed, and teak platform shining like new).

Bert
08-12-2004, 02:25 PM
Ben, Now I am worried. Did that nut gall because the guy was a bit rammy with things or is that a function of stainless on stainless. My 91 has a stainless nut on it. It came that way with a stainless prop when I bought it in 91 and I have never had it off. It's never touched any thing but water so I hope I can keep it that way.

Ben
08-12-2004, 03:45 PM
From what I have heard, the problem is stainless on stainless. I did not view the torquing, only the "attempted" untorquing. It was on there tight, so I'm guessing the moron used an impact w/o paying attention as it "welded" in place.

I'm not saying this happens every time, I don't think I'd freak out, unless you go out of town boating in unfamiliar spots on a regular basis...

My main concern was the prop was not fully installed. Good luck if/when you have to remove it though.

Bert
08-12-2004, 04:01 PM
Thanks Ben, I am concerned since I just move and am exploring new lakes. That's what I was doing when we saw the X star wreck. I hooked up with some locals and they were showing me what areas to avoid. They said don't ever, ever go over there. I said you mean were that wake board boat is? About an hour later this busted up X Star floats up to the dock. I won't be going back to that lake.

NSXBill
08-12-2004, 04:04 PM
I have a lot of aerospace fastener experience. Stainless on stainless (or CRES as we call it) is not the problem. I suspect, as someone else said, he spun it on with an impact wrench or bottomed the nut out. There may be other reasons to use a brass nut, but binding should not be it.

JimN
08-12-2004, 05:06 PM
Did anyone look at the threads on the shaft to see if it was cross-threaded?

Ben
08-13-2004, 08:24 AM
I didn't but probably would have noticed the threads all being really trashed.

In addition to the rumored stainless on stainless thing, I'm thinking the guy no-brainer impacted it on until it was "tight". It was on far enough to see most of the cotter hole, so I don't think it was x-threaded. Since I could slide the prop about 3/4" on the shaft, I don't think the nut was bottomed out.

Like I said, I'm no materials guy (we have a group of smart people that do that stuff for me), so if stainless on stainless is ok, I can't disagree. Just had one guy tell me it is bad. In theory, I would rather have the nut softer than the shaft anyway (i.e. brass). Same way I'd rather have my oil drain plug softer than the oilpan in my truck.

Just giving an example and some comments I've heard that relate to it. Good discussion though.

DanC
08-13-2004, 01:25 PM
When I mentioned the stainless on stainless galling, I was not implying not to use it. Like NSXBill, my company builds military electronics and we use plenty of stainless bolts with stainless nuts. You just have to be careful. One little sliver of metal, incorrect torque.......and once the galling starts, you're hosed.
And as you found out, the real bottom line is that one prefers the weak link to be the cheapest, most easily replaced part. In this case, one would prefer the nut to strip/cross thread and the shaft to be undamaged.