boat stringers
 

Forgive my uneducated question here. I have a 97 ski brendella. I know Its a ski boat and in rough water it rides pretty rough. And I mean ROUGH water. But what are the consequences of riding with bad stringers? Im not even sure I've got wood stringers but I'm pretty sure they are. I understand its like the skeletal system of a boat and you can check it by trying to tighten the motor mount bolts (haven't tried it) but what could happen if you ride with bad stringers? Will the fiberglass hull break in half or something?

Yes, damaged stringers can cause some hull stress, but absolute worst case scenario is motor/trans out of alignment due to rotten stringers. Misalignment can and likely will shear the shaft coupling, sending your prop and shaft into a high speed collision with your rudder sending it hard left or right at speed ejecting you and all of your passengers. Keep an eye on your alignment. Should be able to spin prop with a finger if its aligned properly.

So now I'm a little worried. I went to spin my prop. It wasnt spinning with a little pushing with my finger, then I grabbed it and it spun I'm able to spin it with my finger but its not as easy as say a fan blade, and makes a squeaky noise when I do it. Should I be worried

If its out of the water its not going to spin easy. The strut bearing it water lubricated and gets pretty tough once its dry. Reason your never supposed to put it in gear out of the water. I've never heard the spin it with a finger thing and my family has had inboards for about 25 years now. Reason being when that strut bearing dry's the get tight and squeaky. Maybe with one finger if you swim under while its in the water!!

Any other way to check?

For rotten stringers? You can have a marine surveyor or dealer use a moisture meter on them. Open up all you floor access and look at them where you can. Why do you think they might be bad? Is your floor soft? If you have wood stringers you have a wood floor too. If your floor is ok chances are the stringers are too. Ski boats like yours are very flat when on plane and ride really ROUGH and like crap in chop. Slow the speed down below 20 and get the bow in the water and it will be better, but still not great. I would think you would see ALOT of stress cracking in the gel if the stringers were bad as it allows the hull the flex a lot.

Bottom line the only real way to know is the dealer or marine surveyor. If you are really concerned and think they may be bad thats the 2 places I would go.

1997 your Brendella probably didn't have wood... Your prop won't turn with a finger, maybe not even under water... Drill a hole in them to see if they are wood. Easy enough to do and easy to seal with a some cloth and epoxy resin... You're probably worrying about nothing. We drive my buddies nautique through some ridiculous double ups and his boat is 10 yrs older, with questionable stringers and its fine...

If a prop is not spinning freely, it's out of alignment, period. Especially on a direct drive.

I can spin my vdrive with one finger and have done the same on any alignment job I've ever done.

You don't have to believe me, get your .003 feeler gauge out and measure your shaft coupling faces at 90 degree intervals with the bolts removed. This is a very simple procedure that everyone should do annually but do not. Its the least understood and most overlooked maintenance. It's not rocket science. Misalignment is hell on your running gear and will cause premature wear/failure in bearings, stuffing boxes, shafts, and cause vibration.

I've got wood floors, but they're still solid.

I'm afraid I dont understand the procedure you're explaining.

How long does this premature wear take to manifest?

He is talking engine/ transmission shaft alignment. Nothing to do with your stringers.

Pay no attention to the guy spinning the prop shaft in the dry water lubricated bearing with just his one pinky finger.

@Josh if they should spin that easy I bet I can drive to any of the dealers in my area tomorrow and inform them all their brand new boats are severely out of alignment. As I predict none of them will be spinning like fan blades.

So what should I check?

i predict the same. is that what i said? i don't know how else to explain that the prop should turn easily with pressure, whether or not the cutlass is wet. no, it's not going spin on like some kind of ball bearing fan,

i would start by checking your stringers to see if they're solid. next i would do an alignment check to see if it's aligned. i don't know how much wood, if any was used in your boat. most inboard manufacturers were using 100% composite by the early 90's.

here's a good alignment video. all inboards are virtually identical.
http://www.youtube.com/watch?v=3_w0LvD6gEc

Tom I am curious why you think you have a problem. You said your prop would turn fairly easily once you got it turning. Delta is pretty knowledgable and was fairly certain your boat has composite stringers. It sounds to me like you are a fairly inexperienced inboard owner and just a bit concerned. This is not a common issue in newer boats. If you are concerned about it, IMO, you need to take it either to a reputable dealer who is familiar with floor and stringer work or have a certified marine surveyor go thru the boat. Testing stringers properly isn't easy without the proper meters/tools or the knowledge and experience to know what you are looking at and looking for.

That's a fair statement. I haven't had anything really worry me, although I know my boat gets a little water in the hull and I always drain it, I was just curious as to what rotted stringers would do, which then made me want to check mine. Beyond oil and fluids I'm not very well versed. I will try an impellar change this fall though.