Suzuki DF50 strange noise.?

[Wibs]

As title suggest's

My 2003 DF50 has started making a funny noise at 1000-2000rpm. It's happens every time I power up lightly, with the trim fully down or in a raised position. It sounds a bit like squeaky brakes on a push bike.!!

Completely disappears at higher revs and has no effect on performance.

I had a service back in Oct, and I'm pretty sure it wasn't there at the start of last season, so I'm thinking it's either something that has happened after the service or not long after.?

I did change the prop last month, but have since taken it apart and checked everything is where it should be.

It doesn't make the sound whilst on muffs, it's been suggested that the PTT is playing up.

It's going back to where it was serviced soon, but I wondered if anyone has any suggestions I could throw at the engineer.?

Thanks for any advice.

James

[jyasaki]

Don't know if this is the same thing, but:

My F115 has a bushing around the driveshaft that does that. Known problem; a lot of F115 owners report it. Short tern solution is to drench the driveshaft in lubricant in order to allow it to seep down to the problem area (the bearing lives in the lower unit, just below the powerhead/LU union.)

jky

[Milgrip]

My brand new Suzuki had a slight whine at low rpm and after investigation by the dealer, I was told the following:

"Engine is ok, the noise is caused by harmonics coming from the propeller, this has been apparent on some larger engines before and to over come this metal has to be removed from the propeller itself, the noise will do no harm and probably after you have hit the sand a few more times the noise will go away".

I got them to fit a replacement propeller and the noise disappeared.

[TRevor Lawson]

James as you have just changed your prop this may be a poss reason?how about putting old one back on to test ?

[Wibs]

I'm trying to think if the noise co-insides with the prop change.

I have though about putting the old one back on to see if it does it then.

The new one has been off, re checked, re torqued re greased, but it still made the noise last Sat.

It looks like I'll have to do a run with the old one on to confirm.

I like the word 'harmonics'........as it does sound a little like a harmonica at low revs.

The plot thickens.

[Wibs]

Originally Posted by jyasaki

Short tern solution is to drench the driveshaft in lubricant in order to allow it to seep down to the problem area (the bearing lives in the lower unit, just below the powerhead/LU union.)

Sorry really new to this, and i tend to leave the maintenance to the pro's, I presume the driveshaft isn't the spline that the prop connects to.?

For me to get to the driveshaft, it would require......????

[Wibs]

Ok....

So I've found the problem, just need a solution.

It's def the prop, I put the old one back on and tested yesterday.

No noise.

The old one has been fitted up exactly the new one, so not down to installation.

So, is it a faulty prop.? It came from a reputable online shop (Pacer Marine?) and came in a genuine Suzuki box, but I've obviously fitted it, it now has a couple of small scratches where I've removed the split pin several times.

Any advise.?

[Milgrip]

The dealer that told me about the harmonics, said that by grinding away a tiny part of the welded seam from where the blades are joined to the hub can eliminate the audible harmonic sound wave. I was concerned that if more was ground out of one side than the others, it might cause the prop to run out of balance and cause more serious problems to the engine at a later date.

[Wibs]

Oooff....

Don't fancy that. If the noise isn't doing any harm, i'm quite happy to live with it.

The new prop runs better, so i ideally want to use that one.

I'll see what the company's response to my email is.....