Seized Volvo D1-20 Saildrive, low hours

[Frank 201]

Hi all, hoping to tap into the collective wisdom of the audience.

So my D1-20 saildrive  was at idle and in neutral when there was a "Clonk" sound and it stopped and would not re-start.

This unit only has 350 hrs on it but it is not under warranty (long story won't bore you with detail) 

 

Checks done

• Eng Oil level Normal
• Eng temp at the time was normal (90 degC) 
• Coolant level normal
• Raw water intake/strainers clear and water flowing
• Jabsco impeller check and found satisfactory (had been recently changed)
• No over-temp alarms
• No low oil pressure alarms
• No rope fouled propellor
• Propellor turns freely with gearbox in neutral
• Engine cannot be turned in either direction with a 1/2 inch power bar and socket on the crankshaft V belt pulley.
• All scheduled maintenance up to date.

Questions  re next steps , should I 

• Pull an injector and check for hydro lock ?
• Take Rocker Cover off and check for a bent valve stem ?
• Split gearbox from engine and see if the engine turns freely on its own (implying its a gearbox issue)
• Pull the starter motor off and check pinion/bendix gear etc

I have already contacted volvo at Beaumont street with the same questions in advance of a potential workshop visit

Has anyone else experienced something similar and if so what was the cause.

 

[John B 118]

Geez, I feel for you.

It's hard to imagine a hydro lock from idling ,and for it to lock enough to prevent turning both ways it's more than one cylinder. And it's not a rope on the prop.

So it sounds mechanical to me, but by your own diagnosis you're well onto it and would see anything obvious like a thrown/ jammed up belt. Maybe drop off the belt anyway and check the water pump and the alternator moves.

Best of luck

[aardvarkash10 1,158]

The clonk sound is depressing....

If the crank won't turn in either direction that sounds catastrophic.  Even a dropped valve shouldn't stop the crank from turning.

I'm not sure how easy it is to uncouple the gearbox from the engine.  If it's relatively simple, that would identify if the clonk was engine or gearbox generated.

[Psyche 896]

Unlikely to be hydraulic lock, a clonk and stall could be gearbox related, I would separate the engine and gearbox and go from there. You are going to have to do it anyway from the sound of it.

[Frank 201]

9 minutes ago, Psyche said:

Unlikely to be hydraulic lock, a clonk and stall could be gearbox related, I would separate the engine and gearbox and go from there. You are going to have to do it anyway from the sound of it.

Yes that's where my thinking is headed even if it was the engine I would expect at least some limited movement of the crank even if difficult but this thing is utterly immovable in either direction. The exhaust hose /water lock muffler configuration  etc has given 20 years of trouble free service and the engine was running at the time so I cant see how it can be a water lock. 

[khayyam 110]

I'd guess timing failure but let's hope for something else? Separating gearbox and engine seems reasonable to me but others will know much more. 

[CarpeDiem 563]

Have you checked the gear lever mechanism on the Saildrive? The Morse controller can find some funny midpoint where they are in gear but the prop can still spin.

Does the prop still spin if if you put it into gear? 

Then my next step would be to split the engine and saildrive.

If you have full service records at 350 hours, I we would be making a claim under the CGA.  There's no way Volvo would say that their engines might only last 350hours and that's a reasonable failure interval.  If it was 3500 then that would be different... But 350 is substantially below what any normal person could consider to be the normal lifespan of a d1-20.

[Cameron 108]

did you check the gearbox/saildrive oil level?

 

[Frank 201]

9 hours ago, CarpeDiem said:

Have you checked the gear lever mechanism on the Saildrive? The Morse controller can find some funny midpoint where they are in gear but the prop can still spin.

Does the prop still spin if if you put it into gear? 

Then my next step would be to split the engine and saildrive.

If you have full service records at 350 hours, I we would be making a claim under the CGA.  There's no way Volvo would say that their engines might only last 350hours and that's a reasonable failure interval.  If it was 3500 then that would be different... But 350 is substantially below what any normal person could consider to be the normal lifespan of a d1-20.

The Propellor spins freely with the gearbox in neutral and the gearbox/saildrive oil level is normal, oil presents normal.

Hauling out on the weekend and will split the box from the engine and we will know which half is the cause , I will post the results .

As for CGA, the engine/saildrive was new in the crate purchased 10 years ago for a boat then being built DIY. The project was never completed and the owner started selling off the bits. We installed the engine four years ago and we had to disassemble the crate first. I checked with the Volvo techs as to what procedures to adopt and we followed those.

My money is on the gearbox, we shall see.

 

Thanks for the comments BTW !

[Frank 201]

UPDATE: 

Nothing unusual under the rocker cover, likewise starter motor pinion and ring gear look normal. Got on the phone to the tech at Volvo and he concludes that only a seized big end or Crank Bearing could cause it to lock up with zero lash ie all other possible culprits would exhibit at least 2 or 3mm of rotation on the crank pulley. Can't see any bad reports on the interweb  with Shibaura engines in fact they are considered the epitome of rugged reliability such that even Kubota use them in some products. So its into the shop it goes and we shall see, but I will update, probably in a few weeks, bummer !