View Full Version : 98 Maristar with LT1 (Drivetrain Noise)

05-07-2006, 03:50 PM
I have had the boat out a couple of times now. Friday night I noticed that when turning to the right at above idle through full speed there seems to be an excessive amount of drivetrain noise. It is not coming out of the engine but sounds more like the gearbox/prop/rudder. You can almost feel it in the steering wheel. I still runs great and I am getting all of the R's out of the motor (5,000 at wot)

Anyone have an idea what could cause this or is this normal?

05-07-2006, 03:54 PM
My first thought is a ding in the prop. Apparently I must have hit something once that caused a very small bend in the tip of a blade and it caused a very strange noise and vibration. The bend was only about the side of a nickle but it sure caused problem.

05-07-2006, 04:01 PM
Thanks, I will take a closer look at the prop although I haven't noticed anything obvious to the naked eye.

Additionally, I do not think my speedo is registering the right speed. It has the factory speedo with the paddle wheel pickup at the bottom left side (just of center) of the transom. The wheel spins freely by hand. Is there any way to adjust this type of speedo assembly?

05-08-2006, 11:46 AM
Hey v-drive

Have you noticed any of the noise/vibration getting worse when you operate in reverse? If so, I had the same problem with my 96 prostar. Had a "dampener" plate installed. No more probs.


05-09-2006, 10:49 PM
Yes, I have noticed that it seems noisier when put it reverse, especially when you give it some throttle.

Where exactly does the dampener need to be placed?

Is this a common problem or are we lucky exceptions?

My Bro-in-laws Bu does not make the kind of noise that I am hearing in my boat. Something seems a little strange with the noise and vibration.

05-10-2006, 10:59 AM
Sounds exactly like what mine was doing. I took to my marine mechanic and he ran it on the lake. he heard the same thing. I guess he ended up spending alot of time on the phone to Mastercraft. Here's the short version of what he found out. The noise/vibration was "most likely" normal, but I could take a chance and have a dampener plate installed in the trany. No garrantee that it would fix the prob, but maybe.
Mastercraft indicated that they felt it wasn't that big of a deal. But that noise drove me nuts. Over the winter I took the chance and decided to have the plate installed. Winner.....ding, ding, ding! I think it was about a $700-$800 fix. Alot of coin, but was worth the peace of mind for me.