85 S&S transmission click

[xtnkshun]

Afternoon TT'ers,

I need some assistance from the engine gurus out there. My S&S has a clicking noise coming from the very back end of the trans...near the shaft. It only happens once it is in gear and the prop is spinning. It doesn't happen at idle and shifting into gear is smooth as butter. Trans fluid is good, no metal shavings. I have had the boat in the water and does same thing. Clciks in gear at all speeds. Below is a video link.

http://www.youtube.com/watch?v=VdnHwd0V4Fw

Thank you for your assistance.

[03geetee]

If it is only doing this out of the water it is because your cutlass bearings need water to lube the shaft to keep it from binding and making a horrible noise. Does it do this in the water?

JTR

[xtnkshun]

Yes, it does it in the water. I never Run the prop on the driveway, just did it for a short bit this time to make the video. But, makes the same noise in the water also.

[tockit]

Whatever it is, it doesn't sound good. I'd pull the transmission and see what's going on in there before I ran it anymore.

Does that noise go away when you're under a load (accelerating from a stop, etc)?

It could be the damper if it does, but that sounds awfully loud for a damper.

Might be the input shaft nut has backed off on your transmission.

Basically it's all a guess until you get in there and see what's going on.

If you continue to run it like that you might run the risk of catastrophic drivetrain failure from the way it sounds.

You could try using an automotive stethoscope to figure out the exact area the noise is coming from. That might help you narrow down the source.

Did this noise start all of the sudden, or did it come on gradually?

[xtnkshun]

Hey Tockit,

It's been doing it ever since I bought the boat about a month ago. I didn't really notice it until I ran the boat in the lake with the cover up.

It does get better at faster speeds but still clicks. The loudest point is definitely at very low speeds. The sound is obviously coming from the very back end of the trans where the shaft connects.

Next question is how hard is pulling the trans? I would consider myself fairly mechanical, but removing the trans is well beyond what I have ever done with respect to an engine.

[xtnkshun]

Could this be related to the shaft being out of alignment?

[Cloaked]

Originally Posted by xtnkshun

Could this be related to the shaft being out of alignment?

Yes, it is possible.

Thee are many threads here about plling a tranny out of an Old School. It's really simple as far as removing it. Once it's out and opened up on a bench, it's all right there. At that point, I'd rebuild it, reinstall, realign, but first of all get the shaft issue cleared up. I'd consider that long before I'd pull the transmission. You should have said something about the shaft when posting this issue. Makes for a long day...

Once you clear up the shaft alignemnt your click may go away, but if it doesn't, then you'll know you have a straight shaft / alignment for when you pull the tranny and reinstall it. The 85 model is easy access and straight forward. I'd hate to see you pull it first and not have a known straight shaft to work against you.

A click is typically not an associated noise I'd expect to hear from a misalighend shaft, if indeed you have that problem.

.

.

[Wired_Right]

Go the easy route first.
Disconnect the shaft/coupler from the trans. Push it away (wrap a towel around the prop before that, so it does not hit the rudder).
Run the engine (with water of course) and see if the clicking is still there.
If it is. It is trans.
If it is less. It is both.
If it is gone. Buy a new shaft A.R.E. shaft (http://www.elberts.com/) Strut Bushings and XPC shaft seal from OJ props.

[xtnkshun]

Thanks guys. I didn't really think about the shaft possibility until I read additional threads on here. And the noise sounds like it is in the coupler area.

I checked last night and the prop passes the 'pinky turn' test. A quick visual and the appears to be slightly left in the hole in the hull. And I do have a very slight side-to-side movement of the shaft in the strut. Very slight, but read that any movement at all could mean a bad cutlass.

I'm gonna disconnect her this afternoon and see if the clicking goes away. Will post what I find.

Thank you guys so much for your help. Fingers crossed it not the transmission!!

[xtnkshun]

Alright guys. Got the coupler separated. With coupler completely disconnected the shaft side sits about 1/8 below the trans side. Left to right seems good. There is also a good amount of slop in the shaft and the log. Is this normal?

Ran the motor on water and the clicking was definitely gone. There was additional sound coming from the trans but I am not sure what normal should sound like. I have read posts that say they can be a bit loud on these oldies.

Here is a new video. The video sounds more like a softer tapping noise but in person that wasn't as distinguishable.

http://www.youtube.com/watch?v=X6as1cIDFAU

Thanks again for all the help.