yamaha F100detl noise-please help

[pubertfester]

Hello, please help me with advice: have yamaha F100 detl 2010 year and when i heat the engine apear a noise in lower part ( under engine) (test - i put my ear on the engine cover and is not from there- i suspected the transmision belt). the noise is like a continous creak and it folow the RPM up and down. the noise appear only when the engine is hot, 6- 10 min in speed ( not full 3700- 4500 RPM), wather not up to 50 Grade Celsius and the control wather jet is working.what can it be? - ball bearing? impeller? anything else?
thank you!
sorry for language mistake

[pstephens46]

Sounds like another squeaky driveshaft bushing. Easy to check if you can remove lower unit. Are you able to do this?

[pubertfester]

yes i can. please tell me what i should check?

[pubertfester]

I forgot to say the noise is present all time : when propeller is in gear; and is present when propeller is free( neutral), the noise is a sound like a slipping belt.
thanks in advance!

[pstephens46]

Driveshaft rotates whether in gear or not so that makes sense.

After removing lower unit, look for a shiny spot on driveshaft, maybe 8 inches above water pump housing. That is where it is rubbing and probably squeaking. Grease that spot and the bushing inside where it touches. Put grease on splines at top of shaft also. I use waterproof MARINE grease only. Yamaha makes a special grease for this if you choose to use that. Bolt back together and I bet noise is gone. I grease mine once a year, part of regular maintenance.

[pubertfester]

Thank you very much! please tell me if it is a future problem, or it can be treated with ignore?
thanks a lott for advice!

[pstephens46]

Why not fix it with a little grease? Then you will know for sure it is the problem!
1/2 an hour at most to fix.....

[TownsendsFJR1300]

Thank you very much! please tell me if it is a future problem, or it can be treated with ignore?
thanks a lott for advice!

Its normal maintenance.

If its something else, ignoring it will probably not help..

[pubertfester]

Yes i will do that, is a good advice! i have the boat on the wather that is the reason stop me for a moment, but i will do. when i putt down the lower unit is something to have atention ?

[pubertfester]

sorry if i ask a lott! i have a wather temp sensor ( the optional one - tell me the wather temp - near the oil filter and oil level lever. ) if i go 1/2 hour the water temp gauge show me 50 grade celsius and it mantain that value for all period of trip . is ok? must be upper to 70 celsius? i know if it is to 80 grade is wather temp problem.

[pubertfester]

you know what is this bolt for? oil? wather ? exhaust? is for an optional sensor?
thanks

[boscoe99]

If it is the drive shaft bushing then it is just a nuisance noise. You can grease it if the sound bothers you. If the sound does not bother you you can leave it alone.

As a temporary fix spray a copious amount of a light lubricant on the drive shaft where you can gain access to it under the motor. The lubricant will run down the drive shaft and lubricate the bushing. See if the noise goes away. If so, it was the bushing.

[pstephens46]

Now I know one fellow down here that had a bushing seize on the driveshaft of his 06 F150. Had to have mechanic use some sort of puller to jack the lower unit down to remove it. Not sure why this may have happened, but I have added this to my yearly schedule. T

[TownsendsFJR1300]

^^^, as I re-call, last time I looked at my bushing it basically has rubber "veins" between the outside of the bushing and ID of the bushing (IE its not solid).

I didn't have any issue with it seizing but I addressed it as soon as it was found. Might just be annoying BUT, I'm not going to run it just in case, as you posted, it may seize up with the driveshaft.

Any potential additional damage, IMO, should be avoided as it needs to be lubricated sooner or later. I prefer sooner as to minimize damage..

Doesn't take long to do.. Heck you could do on the trailer in the boat ramp parking lot if prepared with the appropriate tools..

[pubertfester]

Thanks a lot to all for very good advice, for the moment i spray a lot of fogging oil on the shaft, under the engine power had place, i wait 5 min for oil to go down , turn on the key and........surprise.... the noise was gone. i run for 15 min and noise don't reapear".
So, Thanks again to all, and wish you a lot of good beers and some merlins on the wall!