vibrating/knocking noise

[cmayflower]

Hello,

 

We have a noise comming from the engine compartment, it only occurs when under load and only at approx 1300rpm, it has only appeared after our first 50hr service (Beta 43) . It has been suggested that there maybe something around the prop causing the noise, prop and shaft checked all clear. I was hoping to be able to load an mp4 clip I have with the sound but cannot. The sound was not present before the service, but on the first outing the day after service was immediately audible. It sounds like a vibrating/knocking noise.

 

Thanks in advance

[mrsmelly]

There are often many reasons for knocking noises and they are often of little consequence so dont worry. You say you have had a recent service so my first port of call would be to see if the air filter box had been moved and is either loose or now knocking against something at certain revs.

 

Tim

[Guest]

My first thoughts are check that everything that should be tight, is in fact tight: Engine mounts, bolts in drive coupling etc.

I once had a Nissan diesel van that made an awful knocking noise when the fan belt was loose. Never quite understood it, but there we have it.

[Brian422]

I had the same experience following initial PRM 150D gearbox oil change in 2009.

 

Noise was still present after checking for frequency related noises, rattles etc.,changing oil manufacturers and finally using Beta 15/40.

 

I've lived with noise ever since and is still present after intervening oil changes however unit still performs perfectly.

 

I've been told by other boaters that they all do that.

 

I'm wondering whether gearbox was inadvertently overfilled, to allow for oil cooler capacity, when Beta attached gearbox to engine.

 

Did you measure amount of oil removed?

 

Unfortunately I didn't.

 

I won't insult your intelligence by suggest that you should check gearbox oil level but, following e-mails to PRM, was informed that oil level on gearbox dipstick relate to gearbox only.

[Dave_P]

Don't travel at 1300rpm

[cmayflower]

Don't travel at 1300rpm

 

Thanks :-)

 

We've now found out what the noise was, it was the uxter? plate area of the weed hatch and is all sorted now. thanks for the replies