Possible bearing problem

[Tomas_Norway]

My BN-7 have a noise that sounds like "whoosing" sound that is coming from the the gearbox or the rear of the engine. (It is hard to describe a sound in writiing.) To me it sounds like bearing noise, but I am far from an expert in this...

The noise disappears when the engine is under load, but is there at steady, slow speeds up to 35 mph, and at idle. It is not that loud, but can easily be heard. It has been there since i put the engine and trans together, but I think it has slowly been getting worse.

Does anybody have an idea of what it can be?

 

[dancrim]

You could try to narrow it down by stepping on the clutch pedal. This will
pretty much rule out the transmission. Also, could it be the clutch throw uot berring? Adjusted too tight?

 

[bighealeysource]

Hey Tomas,
Sounds like the same noise I would get from my BN6 rear end when not accelerating or under load. Turned out to be the pinion bearing. Under load no noise, but if not would be a distinct whining noise. Not bad, but I noticed it and what was aggravating, only came on after I replaced the pinion oil seal. Think I did not get the nut torqued tight enough and allowed the bearing to just barely move to produce the noise when not under load. Good luck finding it, know noises like that can drive one nuts.
Regards,
Mike

 

[Tomas_Norway]

Thanks for the advice.

Stepping in the clutch pedal does not change anything. I admit ignorance as I did not know that the bearing was adjustable, I will look it up in the manual. But the clutch does "take" at normal pedal travel, so not sure if this is the fault...

 

[TimK]

Maybe a worn pilot bushing?

 

[Tomas_Norway]

If it was the pilot bushing, I would think the noise would change when the clutch was engaged or disengaged. (?)

 

[Randy Forbes]

with the car idling in neutral, rest your ear on the shift knob; does it lead you to believe the noise is emanating from the gearbox or elsewhere?

A similar test can be done with the rear wheels safely lifted clear of the ground and "running" at low speed in 4th (direct) gear.

Using a long shank wood handled screwdriver makes an excellent listening device too. place the tip on various parts of the engine, from front to rear, with the handle touching your ear__do stay well away from the fan!