My new Yam F-40 has a faulty gearbox.

andymach

Cadet
Joined
May 13, 2003
Messages
16
I went to collect my boat with a new Yam F40 4 stroke. When the Yamaha dealer was running the motor to test it, (part of the P.D.I) he discovered that there a noise comming from the gear box when the motor was placed in forward and reverse. It is not particulary noisy. What you might expect if there was play in a gear I suppose, but it could be anything. The gear box is correctly filled wth oil.<br /><br />I am really gutted that a new motor is faulty like this. I am reluctant to take the motor and run it in-case it affects another part of the motor. I was supposed to be taking it on holiday with me.<br /><br />What normally happens with faults like this on new Yamaha engines? I do not particularly want a 'repaired' motor as I have paid top dollar for a new one. Would Yamaha UK expect me to settle with a repair? Should I expect a complete replacement lower unit, or a completely new engine as this one is faulty out of the crate?<br /><br />Cheers.
 

Jammu

Petty Officer 3rd Class
Joined
Jan 25, 2003
Messages
85
Re: My new Yam F-40 has a faulty gearbox.

Is your F40 a 3-cylinder?
 

andymach

Cadet
Joined
May 13, 2003
Messages
16
Re: My new Yam F-40 has a faulty gearbox.

yes it is a 3-cylinder. <br /><br />The Yam dealer tested this on the hose and muffs. The noise is like a metallic rattle that comes and goes. <br /><br />I went back to see him today today. He fired up a Yam 100 hp 4-stroke that was in for its 10 hr service. It made the same noise as mine. This motor just has completed an 80 mile off-shore trip. Then he fired up a 110 4-stroke, again on the muffs and when it was ran in gear it made the noise also, but so quiet you could hardly hear it.<br />All these engines are correctly filled with gear oil.<br /><br />Do gear boxes make a rattling sound like this when ran in gear on the muffs? On 2 similar engines (110 & 100 hp - Yam 4 stroke) is it possible that one be quieter than the other? <br /><br />The dealer has 20 yrs experience and at first thought mine rattling was a fault. He was all for sending for a new lower unit till he heard the others. To me, all the parts in the gear box should run smoothly especially when new and submereged in oil? <br /><br />Can any experienced Yamaha techs shed any light on this?<br /><br />Thanks.
 

juschuzin

Cadet
Joined
Apr 14, 2004
Messages
10
Re: My new Yam F-40 has a faulty gearbox.

Andy,<br /> Im no expert but common sense would say the because of engineering that the teeth in the drive cant be perfectly machined to mesh or it would never select a gear so a certain amount of play would be quite normal. there fore the noise you are hearing is only the teeth rattle as with the nuffs on there is no prop resistance, the motor is designed to have prop resistence in gear, as a dummy like i am i would say put it in a drum and see if the noise is gone once there is resistance?? Maybe a tech can also pass comment on this.<br />Dave
 
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