Volvo Penta D1-30 29hp vibrating in neutral, normal?

[Sirfloatsalot]

It's possible but i'm 99% sure it was started with some throttle on.

Ive just checked the manual as well and it says: "If the engine is cold: Disconnect the gear shift function and move the control lever forwards to half throttle."

Also: "The shift function and engine speed control are combined in one lever. If necessary the shift function can be easily disengaged so that only the engine speed (rpm) is affected by the lever."

Potentially/probably the shift function was disengaged, meaning the prop wasn't spinning at all and the engine was speeding in isolation?

So is it possible that given the engine was cold when I asked it to be moved to neutral, that is the source of the problem? Would that cause such violent shaking? A cold engine?

It does say later in the manual that engine vibrating is either "Defective/incorrect propeller" or "Defective engine mounting"... but ... if the shift function was disengaged the propeller (and shaft) wouldn't be moving right?! ...

Will try and get a hold of this broker again tomorrow and will share any results.

Thanks again

[Pete7]

Originally Posted by Sirfloatsalot

So is it possible that given the engine was cold when I asked it to be moved to neutral, that is the source of the problem? Would that cause such violent shaking? A cold engine?

Yes, because the revs drop.

However, given that this engine needed new parts after just two years and still may have problems, perhaps there are more underlying issues.

"New gearbox coupling to propshaft and new support bracket fitted 2019" Neither item should need replacing unless something happened to to the boat like a rope round the prop or hit something hard.

Take a good mechanic out on the sea trial if you get that far and tell the surveyor before he starts any survey so he can look out for additional problems.

Pete

[Sirfloatsalot]

Originally Posted by Pete7

Yes, because the revs drop.

However, given that this engine needed new parts after just two years and still may have problems, perhaps there are more underlying issues.

"New gearbox coupling to propshaft and new support bracket fitted 2019" Neither item should need replacing unless something happened to to the boat like a rope round the prop or hit something hard.

Take a good mechanic out on the sea trial if you get that far and tell the surveyor before he starts any survey so he can look out for additional problems.

Pete

Absolutely, that's our concern. The reason for that work being done i have been told is because of a leaking stern gland following the new engine being installed. I should also say that i have no reason to believe i'm being messed around, it's all been civil etc

So if i was to go back for a 2nd look what would be my top things to check?

1. Get the engine warm before going into neutral and run for 30 minutes
2. Check the RPMs in neutral
3. Check prop shaft turns by hand out of gear with relative ease
4. Check mounts are secured and in good shape (though i know you can't always tell...)

Anything else?

Thanks again!