Prop

[dancurilla]

Just fouled my prop. Engine runs a bit ruffer in neutral but forward and reverse sound good. Engine seems to be in order . Stuffing box seems normal. Why ruff in neutral?

[Zanshin]

Did the engine stall when you fouled the prop?

[dancurilla]

No

[treilley]

Something either bent, broke or moved. You are likely hearing a difference in the engine vibration. Check your engine alignment and dive the prop to make sure the strut and cutlass are good.

[Zanshin]

Sometimes you can get an injector clog a bit when the engine is stalled, or perhaps from too much compression when the engine is almost stalled. As you surmised, the vibration when in neutral would be not be affected by any mis-alignment aft of the gearbox (unless you are moving when it happens, which I assumed was the case but you should confirm). Have you run the engine under load to cruising RPMs since this happened? What sort of a diesel engine is it?

[treilley]

Originally Posted by Zanshin

As you surmised, the vibration when in neutral would be not be affected by any mis-alignment aft of the gearbox (unless you are moving when it happens, which I assumed was the case but you should confirm).

A strut bent out of alignment would force the gearbox/engine combo out of alignment using the shaft log as a fulcrum. This could easily change the idle note of the engine. Also, I have seen components jammed into the engine compartment so tight that a slight misalignment caused an interference rattle against the component.

[dancurilla]

I have run the engine at high rpms and it sounds good. As the rpms go down it starts to rattle more. Also my stuffing box stuffing seems to breaking aprt in pieces quicker.

[dancurilla]

I take it i shouldnt keep motoring?

[treilley]

Originally Posted by dancurilla

I have run the engine at high rpms and it sounds good. As the rpms go down it starts to rattle more. Also my stuffing box stuffing seems to breaking aprt in pieces quicker.

Please explain. What parts of your stuffing box do you see breaking apart? Normally the packing material would not be visible.

Originally Posted by dancurilla

I take it i shouldnt keep motoring?

That would be a wise choice until you know more.

[HPLou]

"I have run the engine at high rpms and it sounds good. As the rpms go down it starts to rattle more. Also my stuffing box stuffing seems to breaking aprt in pieces quicker."

Sounds like something bent (prop, shaft) or is out of alignment and is heating up the stuffing box to cook the packing. I wouldn't be motoring until I found out what the problem is.

Good luck.