Stern drive growling I think

"I've read that a growl me

"I've read that a growl means that your gimbal bearing is going. However, before I remove the stern drive to see, I wanted to ask a couple of questions.

The growl is much more pronounced when turning to the right, and barely noticeable when turning left. Is that consistent with a failing gimbal bearing?

I have a bunged up prop; could that be causing the sound?

Further background: last november, when I pulled the outdrive, the u joints and everything were in excellent shape. There was a little puddle inside the bellows, but I wrote it off at the time, because the U joints and drive shaft looked so good.

Also, is it possible for the stern drive to be out of alignment, and maybe that's the cause of the noise?"

"Have you tried greasing it?

"Have you tried greasing it?
Prop not causing the growl. In less time than it would take to explore all the options in type, could have your drive off and feel the gimbal to see if it's rough. That's the only sure way to know. Puddle in there not good. and yes, sounds like your alignment issues might have killed the gimbal brg - check the alignment."

"Yes, I have pumped some extra

"Yes, I have pumped some extra grease into the zerk fitting at the gimbal (engine running) ....didn't seem to make much difference. I greased it last november too, when I did my winterization chores (engine not running that time).

I just hesitate to pull the drive without good reason, because I couldn't get it back on last time. Maybe I'll have better luck this time."

""the U joints and drive s

""the U joints and drive shaft looked so good...I just hesitate to pull the drive without good reason, because I couldn't get it back on last time."

Either the U-joints have gone south or the engine alignment is way off and chewing up the splines in the coupler and damaging the gimbal bearing. WHAT MORE REASON DO YOU NEED TO PULL THE OD?

Did you check the alignment the last time you had trouble getting the OD on?"

"Yes, I checked alignment then

"Yes, I checked alignment then. I'll pull the drive."

drain the OD fluids and see wh

drain the OD fluids and see what you find. I just had the upper bearing in mine fail and if I didn't have twins I would of been stranded in the middle of the bay.

"Status update (pics to fo

"Status update (pics to follow):
Pulled drive, everything looks OK. Used alignment tool, and it looks like things are aligned. Examined U joint, splines, gimbal, no sign of rust, and bellows was dry. Feeling the gimbal, it was very smooth.

Popped the top of the outdrive, and it was full to the top with good looking stern lube (no milky oil, no sign of water in the oil). Drained some of the oil to have a look at the gears there, and they both looked good.

I tried turning the drive shaft by hand, and it was pretty hard with a grinding noise coming from somewhere within the lower part of the outdrive. I'm hoping that the noise is because the impeller is dry, and nothing more. Are there any more tests here I can do before I put the outdrive back on?"

"Alignment: and a question...

"Alignment: and a question...how far should the tool push in? is this enough? The double-black-mark (the one without the F next to it) is the distance that I can stick in a really small metal rod into the drive. So the alignment tool bottoms about about 1 1/4" before that one does.


Pic of the gimbal. I know you can't see much, but I tried

"

"As far as I can tell, the Ujo

"As far as I can tell, the Ujoints and drive shaft look good....


Popping the top, oil looks good and looks full.


Draining a little oil, the gears look good.
"

"while the drive is off, just

"while the drive is off, just start the engine for 15 seconds or so and make sure the growl isn't still there (was thinking the starter pinion or something)"

"Daniel;
A couple of points:

"Daniel;
A couple of points:
The upper gear cavity should not be full to the top with oil. It should be at the level of the vent screw only. There has to be an expansion space in the top of the older drives, as there is no external bottle for the lube to expand into as it heats up.

A growl in the lower drive is a concern; especially if you can hear it with the drive full of lube oil.
Did you check the fluid you drained from the bottom for fine metal grindings or flakes?
Best method is to put a few drops into the palm of your hand and rub it. There should be nothing gritty or rough.
If your drain plug has a magnet, there should be nothing more than a few whiskers of metal attached to it. Any more means trouble, particularly if they are salt crystal size and shape.
If the lube oil is clean, your gears and bearings are likely OK.

What about your U joints? If you grip either side of the joint and twist hard, do you get any play? Any play at all means change them out. Best to do this test before you grease them. Make sure you grease them bofore reassembly.

If all this turns up OK, I would change the gimbal bearing just on spec. They are cheap and if its been in there a few years, it should be changed.

The alignment tool needs to go in as far as your drive shaft. The drive shaft nearly bottoms on the gimbal bearing at the shoulder of the front U joint yoke, so measure this distance (about 9-1/2 inches) and smear some grease in that area on the alignment tool. You can then easily tell if its going all the way or not.

Just my thoughts.

Rod"

"Thanks fellas!

Hy: there i

"Thanks fellas!

Hy: there is no water coming from the outdrive for cooling...is it still OK to crank and run for a short period of time?

Guy: I didn't know to check the lube oil that I drained for metal flecks; I'll go and check, as I collected it into a relatively empty oil container.

I do have an external lube bottle, so I think I'm ok on the oil being full to the top.

As far as the drain plug magnet...well then, I didn't know what that stuff was, but yes, there were whiskers of metal there. A good many of them, although at the time I didn't know what that was...I thought it was just because I dropped the drain plug into a paper towel. I wish I had taken a pic of it. They were definitely whiskers, and not of salt crystal shape, if I know what you mean.

As far as I know, no play in the U joints. And I've already regreased them via the zerk fittings on each U joint.

Gimbal was changed in 2004 via a marine shop.

And I'll measure the alignment tool and see what's up there; thanks for the tips."

"No play that I can tell in th

"No play that I can tell in the U joints. Alignment tool slides in about 1/4" further than the driveshaft would if inserted straight, so I think things are Ok there.

And no metal flecks in the captured stern lube as far as I can tell."

"I think I'm about to stic

"I think I'm about to stick the outdrive back on, and see how it goes.

There are a couple of other things that it could be...I put on a different hydrofoil about a month ago, and while I'm not sure exactly when I started noticing a growl coming from back there, I'm going to pop the hydrofoil off to see if that makes a difference. Also going to either recondition or buy a new prop, and see if that makes a difference.

I just don't see anything at all wrong with the outdrive. I guess it's possible that something is messed up in the lower gearset. Are there any further checks I can do while the drive is off?

And if I were to try, how do I get the gimbal bearing out? And if it's OK, can I put it back in, or do you ruin it getting it out?"

yes you can run it for 30 seco

yes you can run it for 30 seconds or so without water.

"Daniel;
Even with a lube oil

"Daniel;
Even with a lube oil monitor, the upper case is not supposed to be completely full of oil. Up to the vent screw is the correct height.

If you are putting it back together you should put an hour or two on it, then pull it, and recheck the bottom drain for more metal particles. If you get a bunch more in that short a time, you know you have a drive problem.
Then its your call as to whether you run it till it fails, have it torn down and serviced now, or replace it with new.

A hydrofoil will not cause a growl, IMO.

Rod"

"Hmm, I don't know what wo

"Hmm, I don't know what would cause the oil lube level to be so high then. I took that picture above right when I pulled the top cover, and thought that it was higher than expected, and then was happy that the gears are bathed in oil.

I definitely want to fix anything that's wrong, but right now I'm just not knowing what it is.

Another thing is that what I'm describing as a growl, if one of you were here, you might say "oh, that's just ventilation" or some sort. It's hard to describe sounds over the wide wide world of web

The drive is back on, and I'm taking it to the water in a bit. At least now I'm not scared of taking the drive off, as I've proved to myself that I can get it back on by myself "

"Thinking more about the gear

"Thinking more about the gear lube being too high, maybe the little check ball at the stern drive interface (where the stern drive splits from the gimbal housing) was stuck open? It did not drain while I had the outdrive off though."

"Daniel;
The "anti-dribbl

"Daniel;
The "anti-dribble" valve you refer to is pushed open anytime the drive leg is on the transom assembly, and closed off when not. This is so that it won't leak when the drive is pulled.

Normally there will always be an air pocket in the top. The fact that yours was full may mean that your top cover O ring was not sealing completely, and let the air escape over time. Otherwise, I don't know.

Rod"

"That's possible Rod. The

"That's possible Rod. The mechanic that helped me put the leg back on at the beginning of this season opened the top cover, filled it with lube, and just bolted it back on. When I took it off today, I was careful to put some Perfect Seal where the manual said to, and to torque the cover bolts to the proper torque.

I guess I should remove the vent screw and let whatever oil wants to drain out, drain out. I didn't know that the level was too high, so I filled it to the same level before reinstalling the top cover."

"Daniel,

All gen II's w

"Daniel,

All gen II's with the external bottle fill all the way up. When installing a brand new outdrive when rigging a new boat for the first time or when draining and servicing the outdrive then filled to the upper drain/vent plug and as soon as you fill the res bottle or unclamp the line when draining and servicing. The gearlube in the bottle drains into the upper gear case. Believe me.......

Any air gets displaced with the gear lube and the air travels back up the rubber hose and does not leak out any orings.

You are fine with what you see.

As far as your alignment tool if it is home made then you need to get a real one and get a mark made on it (NOT WITH A PEN EITHER)because the merc tool only goes in far enough to get ~ 2 to 2 1/2 inches of penitration into the splines of the coupler. It has a shoulder on the shaft and it that restrics it from going in to far.

Also if you grease the end and stick it in and you feel you have good alignment then stop spinning and pull it straight out and you should see the spline marks in the grease.

At this point if it were me I would add up what is going on.

You hear the noise but you are still able to drive the boat? correct? If you had a gear issue you would be done! End of story.

Gear lube is clean = no issues!!

Gimbal bearings can feel ok but it takes a good sense of feel to determine that. Typically when one starts to go you hear it when steering end to end on both sides of steering travel.
The fact that you only heard "SOMETHING" in one dierction could be nothing more than harmonics due to strain on the what ever............

Put it all back together and go out and run it.

If it breaks then you will know for sure what is wrong. It will be better than trying to find it now if it even exists.

Try not to be to paranoid about noises. When and if you ever loose a gear in the outdrive you will surley know it."

""I have a bunged up prop&

""I have a bunged up prop"

Out of balance props can cause vibration noise and bunged up props cause cavitation noise. Change the prop and inspect the spindle for straightness. Hope the noise goes away. "

"ty much kghost, that does put

"ty much kghost, that does put my mind at ease as of now. It is true that I hear more of this growling noise turning right than I do left.

I took it out this evening for about an hour, without the hydrofoil on; I still hear the growling when turning (still stronger on right than left), but it was much softer in volume.

On the alignment tool, it's a real one, not homemade.

Guy: ty...I've pulled the prop and within a couple of days I'll either have a new one or a reconditioned one.

Boats are so interesting...always something new to learn...I've only been boating a year now but I love it."

Daniel:

Buy another prop be

Daniel:

Buy another prop because you need a spare. See if the guy doing your prop has a recond. prop for sale. New props are cheaper in Dec. & Jan. since sellers are trying to reduce their inventories.