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Tyfab14
18-04-2019, 12:41 PM
Hi,

I have had this bearing noise in the middle section for such a long time that needs extra care now.

I was thinking that it was coming from the the lower bearing in the crankshaft but i diagnosed that the bearing is fine. The power head makes a little bit of bearing noise but not that significant to be honest. (it is a 25 yo outboard)

So I removed the leg and started to check if it was coming from the driveshaft bearing.

Bearing noise in the middle section (beginning of the video):
https://youtu.be/cdbEvyNzX6c

Here is the bearing noise from the leg:
https://youtu.be/3ACOMdGDTBA

It sounds the same as the noise from the middle section. Which means the noise may travel travel through the drive shaft. (there is no bearing in the middle section)

What are you thoughts? Has anyone had this issue before? Easy fix? Would I need to remove the entire driveshaft to locate the upper bearing or I can get away just by removing the nut?

Would require new bearings and seals I guess and lots of elbow grease.

tunaticer
18-04-2019, 03:13 PM
Drop the oil from the gearbox. If it is milky you will have problems.
The oil drain plug will likely be magnetic so it will show and bearing fragments if damaged.
If no metallics show up and the oil is good, fill it up and reassemble the motor.

Tyfab14
18-04-2019, 04:18 PM
I dropped the oil - it is blue ish and slighlty milky but not gooey (the leg needs a service, the oil is 1 Year old).

Example:
119049

There is no apparent metal on the magnet.

Noelm
18-04-2019, 07:24 PM
Not exactly sure what you mean, the top bearing in the gearbox that the drive shaft runs on is not a 5 minute job to replace, it's easy enough, but requires exact adjustment of the driven gear "lash" the bearing on the crankshaft on the bottom of the motor is a big job to do, not sure which bearing you mean.

frank100
18-04-2019, 07:33 PM
Hey Ty , Are you sure there is no "bush" type bearing towards the top of the drive shaft ? My old suzi 140 used to have a plastic bush on the drive shaft (maybe halfway up from the water pump) which was lubricated by coating the drive shaft with water resistant grease (the manual called it a bearing ). If the grease was not applied at service it did not take long to start squeaking.
Hope this helps
Frank

gazza2006au
19-04-2019, 01:44 AM
Go buy a mechanics stepascope, start the engine and list to where the noise is coming from

Stepascope was on of the best tools i ever bought

PixieAU
19-04-2019, 05:46 AM
Stethoscope

scottar
19-04-2019, 07:56 AM
Run it with the leg off using a garden hose fed into the water tube. Will at least isolate it to some extent.

Tyfab14
24-04-2019, 02:06 PM
Run it with the leg off using a garden hose fed into the water tube. Will at least isolate it to some extent.

Yup i did that and it does not make any significant bearing noise in the crankshaft.

I'll leave like that for now and probably order a newish leg next summer as the powerhead is spotless, runs like new since i changed the switchbox and tuned it.

But I am off for 3 months anyways as I fractured my hand on Good Friday ..... Oh well!!

gazza2006au
24-04-2019, 03:36 PM
Tyfab i once bought a smick looking 30hp Suzuki the elder 90's model grey model's it looked brand spanking new the powerhead and the internal exhaust chamber was all corroded, so don't always go by looks mate can be deceiving