Clanking SD60

[crayiii]

I have twin 4JH57 Yanmars with SD60s. I'm at 280 hours and one of them has developed a loud gearbox. It's intermittent in that if I start it up and it doesn't make the noise, it won't start making the noise but if I start it and it makes the noise, it will continue doing so.

It sounds like partially engaged gears and sounds the same in forward and astearn and increases with revs. It does not make the sound in neutral.

The Yanmar tech was just aboard (I'm in Grenada) and of course it wouldn't make the noise although he said it was louder than it should be.

The plan is to have them pull the assembly and take a look and hopefully do what needs to be done while we're in the water.

I'm wondering if anyone has heard of this issue? Anything else it could be? We have flexifold props, could these be making the noise?

[crayiii]

The Yanmar mechanics separated the engine and saildrive, remed the saft and inspected it on the bench, at first said the flexplate was bad but then put the same one back, then said the shift cable was bad so they replaced it. Now the noise happens every time the engine is at idle while in gear (forward and back).

They just told me to use it until it breaks or until we haul out.

Here's the sound I recorded https://youtu.be/iqSirf_ijPE

You can't really here it in the engine compartment buy outside next to the hull you can.

[crayiii]

Well, oil started pouring out from the bell housing and the mechanics figured they put the seal on backwards. Out came everything for the second time. This time I've asked them to replace the damper plate even though it looks okay.