Yanmar 1 GM10 , Noise from Gear box or the propeller shaft??

[Boffin]

I have re-engine in my Yamaha25 with 1GM10. It works fine for some 120hours , then when the rpm goes between 1800 and 2300 , there is a hight frequency noise like VVVVVVV from the bear box or the shaft . There is no such nosie under netural condition. And no such nosie in reverse rotation .

Any one has such experience ?????

 

[Blitz]

Any vibrations?

Does it just clear up above and below those RPMs?

What was the condition of the engine clutch and transmission when you put them in?

 

[zeehag]

Re: Yanmar 1 GM10 , Noise from Gear box or the propeller sha

did you check tranny for oil???? my borg warner made fun sounds when it was close to empty of fluids....check that first.

 

[Boffin]

Re: Yanmar 1 GM10 , Noise from Gear box or the propeller sha

Thank for the reply . There was no such noise below and above the said rpm.
In fact , the boat was just launched and cleaned . The vibration is normal when the gear was engaged. And the transmission /clutch shown no abnormal noise when I engaged the forward gear . The oil in the gear box is clean and full . It is too early for the gear box becomes wear for just 120 hours used .

 

[Blitz]

Was the tranny rebuilt or just the engine? New clutch? New damper plate?

Even if clutch and damper plate is new It sounds like to me like a common condition in which the transmission cone needs to be resurfaced or unglazed. Sort of like disc brakes that need to be recut before new pads.

Oil is always important as noted and the best place to start.

 

[Boffin]

Re: Yanmar 1 GM10 , Noise from Gear box or the propeller sha

This is new engine and gear box , it has been running for 120 hours and then that noise comes out .


I am going to disconnect the shaft coupling to check whether the noise is from the gear or from the shaft bearing .

 

[Dancing Queen]

Re: Yanmar 1 GM10 , Noise from Gear box or the propeller sha

My Yamaha 25 is re-engined with 1GM10 also. It has more than 200 hours and everything is fine. May be that your new engine has wrong position? It is strange and interesting.....

 

[furdui]

Re: Yanmar 1 GM10 , Noise from Gear box or the propeller sha

my boat makes "your vvvvvvvvvvv sound" at high revs since last time i had it out for antifouling.
reason:after i've installed new zinc anod on the shaft,between propeller and cutlass,i wrongly,thought the old zinc anod,75% good,would still be helpful and i installed it on the other side of cutlass,but approx 150 mm away,big mistake!,and because this old zinc anod is 25% corroded,i've ended up with a unbalanced load on the shaft and in a wrong place!
until next antifouling i have to put up with lower revs(anyway,the boat is a sailing boat,why the need for high speed!) otherwise the cutlass bearing may be affected.
the noise is tipical of a unbalanced load on a high speed rotating shaft.