ive noticed it before but it seems to have gotten louder. when i just crank it in the yard and let it run a bit there is a small spot at the low end of throttle and at idle where im getting the most god awful noise. hard to explain the noise, but just curious that if someone else with more knowlegde may know if this is normal or not. i can bump the throttle and it will go away and ive not noticed it in while in the water.

Where's it coming from? Motor? Shaft?

kinda sounds like the shaft. when it does it it looks like the prop may be changing speeds or someting. hell its probably an illusion since everytime i hear a strange noise i get ready to rebuild the whole dang motor... eternal pessimist lol

sounds like shaft chatter. Its more than likely time to change the bearings, wiggle the prop/shaft side to side there shouldn't be hardly any play.

or your U-joint might have slipped on the shaft and is slightly out of alignment.

Sounds like the prop is loosening and tightening. I was worried at the noise coming from mine new out of the box. The manufacturer said that's what it is. If it is the same noise than it is normal

i dont have any play at the prop , how do i check alignment of the u joint... its a 23 horse go devil that were talking about by the way.

When running in or out of water does the shaft tube get hot? If the shaft and engine are out of alignment and causing the shaft to ride high or low in the tube causing the bearing to make noise, noise loud enough to hear while running I would think it would cause the tube to heat up. Now the bearing my be bad from lack of grease. Either way to replace it you will have to remove shaft from u-joint yoke. Might as well replace Lorraine bushing &seal and upper bearing &seal then reinstall and realign shaft. This procedure is outlined in the operation manual. Hope this helps.

The prop should loosen and tighten

^^^×2. I can hear mine pop free when i pull out of water/mud while under a load

im leaning toward the prop loosening and tightening because the bearings and seals were just changed 2 years ago and it hasnt been rode a terrible lot since and i keep it greased very well. appreciate all the input guys.

i cant hear it when im running in water but when i am just running in out the water, i can hear it at one little spot in the throttle. i can just bump the throttle just a small bit and it will stop.. it doesnt affect performace and it isnt causing any excessive vibration so i guess its ok. i just like to know what every little noise is so i can fix it before it causes more problems or leaves me stranded.

You'd freak the hell out if you heard a Prodrive in gear out of water then!

Is it a horrible cyclic metal on metal rattle/vibration at idle speeds that comes from the back of the motor? I just had to deal with that recently.

If this is the sound, you have slop somewhere in your PTO/u-joint/shaft union. In my case, the u-joint was replaced sometime along the line with a non-Go-Devil u-joint. The only difference between the off-the-shelf u-joint and the Go-Devil u-joint is that the GD uses a 1/1000" oversized key for their application. My key was loose and vibrating out of the key way, which caused slight slop where the collar of the u-joint seated over the PTO. Once I replaced the key, the sound went away. It is a simple enough repair, but I should have replaced the entire u-joint while I was at it because the process took just long enough to be annoying with the tools I have on hand.

I suspect a wore out u-joint or upper bushing or loose connection between the shaft and the u-joint could sound the same.

Nate

browndog, you have me rethinking my problem again. i did have to have a new key put in bout 2 years ago. i had the rear gasket replaced and when the shop put it back together they didnt put the wire on the bolts and they vibrated loose and threw the key. i did not take it back to the same small engine shop. i took it to kenn tenn motorsports cause they said they did work on go devils. so i woud figure he would have used the right parts but who really knows.

its most probably your prop bud...mine did that to with a 23 gdsd...when you get on the gas a bit its binding the prop up cutting out the noise mine would clack sometimes at low idle..just the prop loosening and tightening

Like I said, if it is a horrible CYCLIC metal on metal clatter coming from the back of your motor at idle speeds, it is likely slop somewhere in your PTO/u-joint/shaft union or the upper bushing. If the sound does not fit these criteria, I have no idea what you may be hearing and you should refer to the other guy's advice.

The back and forth movement of the prop shaft due to a u-joint will make ANY loose area in that region clatter. The connection to the PTO is just one of several places. Under power, the slop is dampened by torque and rotational stability and goes away.

I've read about prop clank in the GD owners manual, but mine hasn't done that yet, which means my prop is petrified in place. It is supposed to occur as you fluctuate power or load, e.g. when you remove it from the water or put it back in. I wouldn't expect it to be cyclic, but maybe it could be? I also wouldn't expect prop clank to eminate from right behind the motor either, but you can't tell when you are in the boat. This is something you'll need to check while the boat is on the trailer.

Nate

browndog , i took my boat out for a while today and i think i am going to order a new u joint from go devil and replace it and see how that does.. i believe the noise im hearing is more than just the prop cause it sounds like its bout to rattle itself to pieces. when i had the key replaced a couple years back they may have very well went back with a smaller key just as you mentioned because around that time is when i believe i started noticing it being more loud than usual and it appears to just be getting worse. thanks... im not very mechanical, so is changing the u joint somethin i need to have done or is it fairly simple.

Changing a u-joint is simple. I changed mine last year, i didnt order from gd, their parts are a little spendy. If you take it to a parts shop they should be able to measure it and get you fixed up. Mine was $11 and took about 10 minutes to replace. Are you guys talking about the shaft coming out of the motor with the key?

Drake,

As mentioned, it is easy. You have to unbolt the motor mount bolts to shift the engine forward to get enough room to work. I ran a ratchet strap from the frame around the front of the motor to keep the motor from falling forward. You also have to hold your mouth right to get the u-joint hub lined up on the PTO. This is the most frustrating part, but take your time and it will start. Everything else is just tapping with a hammer and pulling wrenches. Once you get it started without binding, you just tap one tip of the "U" a couple times, then tap the other side of the "U" a couple times. Repeat until it is seated where you what it. After I seated the hub on the PTO, I repeated the process on the prop shaft. I'd tighten the ratchet strap a few clicks every few rotations of the shaft to pull the motor back toward the prop shaft.

Flat,

Yes, the shaft off the motor.

Nate

I would bet the yokes are fine and only the joint needs replaced.

There is almost no doubt you are right, but I think a GD u-joint for my motor is $27. By the time you pull the u-joint, take it in, get it rebuilt and explain for the 8th time that you need a key that is 1/1000" bigger than the key that came with that size u-joint off the shelf, just swapping the whole thing out with a OEM GD u-joint and being done with it is pretty attractive. He said he isn't terribly mechanical, so I doubt he'll want to rebuilt it himself.

Nate

What key are you referring to? I pulled the joint out of the yokes had it measured and bought a new one. It was $11. Unbolting the motor and moving it around sounds like a pain. The joint I bought went in just fine, 75hrs later and no problems. Maybe I'm misunderstanding something.

Nevermind, think I see what you are saying now. But you can put a new joint in without removing the yokes, very simple.