I am new to the site and new to the hydrodyne boats.. today i bought a 96 hyrdro grand sport from a buddy. it has a ford 351 engine in it and a one to one tranny. before he put the boat up for the winter he noticed that it had been losing speed. and is now down to goin nowhere. he thought some clutches in the tranny was worn out but not for sure. i notice one fin on the prop was bent a little. Just lookin for a little advice on where i should start.
While there are a handful of us inboard owners on here, you'll probably get better response to your question over on one of the nautique sites (i.e. planetnautique.com, correctcraftfan.com), as that vintage of nautique commonly used the exact same power-train (in your case GT-40 and Velvet drive I believe) as the Grand Sport did. From your description above, I'm also not quite following your problem. Is the engine operating normally, and just not getting the power down to the prop? If that's the case, it definitely points to the transmission, or a transmission-related problem. If the engine performance was degrading and the ultimate culprit, then you need to chase down the cause and remedy it (fuel/air/spark/etc.). Regardless, there's a larger knowledge base on one of the nautique sites. The bent prop ear indicates something was hit somewhere along the way, and should be fixed. A small ding may cause some vibration. If it's good sized bend/ding, you can cause problems up the drive-line (shaft/transmission) if you continue or continued to run it hard. You might need to check your strut and drive-shaft for proper alignment. Either way, the prop at the very least, should be repaired or replaced. If it's right out at the tip only, I've had pretty good luck hammering/filing out small dings. Anything beyond that gets a trip to the prop-shop for me.
i realy appreciate your help tom. earlier today i narrowed it down to the trans. i had check the propeller hub and the shaft. im now guessing its the clucthes in the tranny. my prop has a slight bend on the tip of one fin. its not bad enough to effect much i dont think. do u have any idea on what a trans rebuild costs?
I have no clue what a transmission rebuild costs. It depends if you're going to tackle it yourself, or have it done. Check with your local marine mechanic (find one that actually works on inboards though), for costs going that route. If you want to try yourself, I'd talk with the folks over at www.skidim.com and they can likely help diagnose and set you up with the necessary parts. Keep in mind proper alignment of the tranny when it's put back in is very important, otherwise you'll likely generate additional problems down the road if you end up out of alignment.
