Large rattling from engine

[lawrence_craig]

Hi all,

Today, when going slow ahead foward, the engine started rattling very loudly. The location of the sound was roughly in the area of th transmission/damper/sail drive.

I can still engage forward, netural and reverse. The sound is still there when in Neutral so have ruled out gearbox and saildrive issues.

Its a Volvo Penta D2-55D.

Any clues what it can possibly be?

Going to get a mechanic to have a look at it but thought I would try get an early idea.

Many thanks.

[model 10]

Loose springs in the drive plate would rattle in neutral too.

[DeepFrz]

My guess would be the damper has disintegrated.

[lawrence_craig]

Originally Posted by DeepFrz

My guess would be the damper has disintegrated.

Hmmm...I was thinking along the same lines. I had previously had a 'knocking' sound coming from the same area when in neutral so was planning on changing it.

Can the engine still be run with it in tatters?

[model 10]

At some point the center hub will come free from the mounting disk. I would baby it till then.

[DougR]

The input shaft of the saildrive rotates all the time whenever the engine is running, regardless of whether it is in neutral or not, so you can't totally discount the upper gearbox on the sail drive as being the source of the noise.

But, in all probability you have a failing torsional damper on the flywheel. This is a two stage rubber element built by a German company named Centa, and they were problematic early on the the D2-55 model progression. I would suggest not running the engine if at all possible until the damper is examined. It's possible that a loose part could get trapped and driven through the flywheel housing by the flywheel. There are several threads about the damper here on CF that you can search.

By sliding the engine forward about four inches from the saildrive it's possible to change the damper without too much problem, assuming some reasonable access to the area.

DougR

[oldcal46skipper]

This type dampener plate attaches to the engine's flywheel and the gear box input shaft is centered. If the coupling to prop shaft coupling is misaligned this can happen

[Uncle G]

We once had a Volvo engine with saildrive that developed a rattle. Turned out that the anode in front of the prop had come loose...

[lawrence_craig]

Thanks for all your info guys, really helpful. I bit the bullet and pulled the engine to check the damper plate. Found part of it sheared off causing the rattling so now looking to replacing.

Frustrating thing is the previous owner was obviously aware of issues as I found a tack weld on the plate meaning they tried to repair instead of replace. [emoji849]

[sdowney717]

Originally Posted by lawrence_craig

Hmmm...I was thinking along the same lines. I had previously had a 'knocking' sound coming from the same area when in neutral so was planning on changing it.

Can the engine still be run with it in tatters?

Dont push it hard or far, maybe just idling around.