Ran over a gravel bar - Now what?

Fam-manFam-man Posts: 166 Baller
Yesterday my boat, 98 Ski Nautique 196, was driven over a gravel bar. Nobody was hurt and there wasn't much damage to the hull but it was a little hard on the running gear.

I've checked the driveshaft with a dial indicator and the total runout is .012" which I believe to be out of tolerance, could somebody confirm this. This measurement was taken close to where the driveshaft goes through the hull.
What is the best way to check the condition of the strut? Take the propeller off, disconnect the transmission coupling and remove the packing assembly to see if the driveshaft is centered going through the hull? Is there anything I should do before this step?
Is checking the drivetrain alignment done with the coupling completely disconnected or with the bolts just loosened?



  • BraceMakerBraceMaker Posts: 2,918 Mega Baller
    You want to take that measurement by the prop too for run out.

    Disconnect coupling and check alignment with a feeler gauge, you want to remove the bolts so that you can "clock" the two couplings in different places to ensure the flanges are co/planar and not bent.
  • dvskierdvskier Posts: 335 Solid Baller
    Tolerance is .003".
  • BraceMakerBraceMaker Posts: 2,918 Mega Baller
    That tolerance of .003" is usually over some distance. Not point to point so its a hard measurement to take unless you pull the shaft and set it on rollers.
  • eleeskieleeski Posts: 3,660 MM Trick Skier / Eccentric Person
    How does it drive? If it shakes too much, replace what you need to get it smooth enough. Usually the prop. I find it really hard to measure accurately in the boat. Especially in older boats with some wear in the strut and packing. Loosen the coupler bolts and you might see really bad problems. If it's a little out but runs OK, enjoy it until you hit the next obstacle.

    FWIW, I have had to replace shafts and struts. Not impossible but it takes a couple hours. Replaced lots of props. Some new or rebuilt props vibrated a fair amount.

    What do you order in a "gravel bar"?

  • Fam-manFam-man Posts: 166 Baller
    Thanks all for your input so far.
    It went through pretty hard, the tracking fins are beat up, the drive shaft has some gouges in it, the prop is toast and there was mud on the strut and rudder.
    It drove back to the dock but only at idle and there was significant vibration. Due to water levels cant back the trailer in very far and there was massive shaking putting it on the trailer.
  • GarGar Posts: 268 Baller
    May be best to straighten tracking fins, install new shaft, strut with bushing, prop and closely check rudder.
  • gregygregy Posts: 2,459 Mega Baller
    Years ago I ran a boat onto a sand bar. Bent the strut, rudder, prop, and shaft. Shaft was bent enough so that you could see it. I talked to several mechanics and shops about getting it straightened and everyone said no way. I started calling prop shops and Baumann Props in Houston Tx said no problem. They straightened the shaft, strut and prop. They tried the rudder but I ended up having to replace it. I ran the boat that way for several years and sold it to friend that owned it for several more years.

    As far as fiberglass damage mine had a couple cracks radiating out from the strut mount area and after talking to some glass repair shops I decided to take may chances and try it.
  • lpskierlpskier Posts: 2,243 Mega Baller
    Call your insurance agent and report your claim.
    John Wilkins- Si non pro sanguine quem ludus ne. #iskiconnelly
  • Orlando76Orlando76 Posts: 785 Crazy Baller
    Contact Jody Seal or try correctcraftfan.com for good used tracking fins. Getting run out measurements in the boat is pretty darn hard as already mentioned. So many factors, I had to set my boat trailer on jack stands to get a close enough measurement.
  • BoneHeadBoneHead Posts: 5,921
    Baumann's straightened a shaft for me too.
    Shane "Crash" Hill

  • DWDW Posts: 1,864 Mega Baller
    @Fam-man : .012" at the location measured will probably open up the shaft seal clearance allowing more water to enter the bilge. I would expect you would be able to see that amount with simply rotating the shaft. If you go to have it straightened, a magnaflux or crack check would be a good idea.
Sign In or Register to comment.