Help required!

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Topic

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Help required! 13m tsmy with 2 x Perkins Sabre M225TI. Used regularly and extensively without a mechanical issue until family matters necessitated a two year stopover in La Rochelle. Lifted out in June 2017, bottom, rudders, props and shafts scraped and polished, new anti-fouling to hull. Local Perkins agents renewed ME wiring harnesses and serviced engines including fuel and oil filters and oil change. Gear test before departure all running fine. Part fuelled at Minimes on the way down channel enroute to Royan.

Open sea and discovered engines would accelerate to 1100rpm but no further ( max 2400). Continued down the coast and stbd engine died. After 10 mins restarted and noted erratic movement on flow meter. Died repeatedly but restarted after say 15 mins. Concerns over port engine increased anxiety. Weather deteriorated to NW F6 with 3m swells. Arrived late but safely in Royan.

My own analysis rules out electrical, injectors and filters so any thoughts would be helpful. Next leg is Biscay and can’t do that unless both engines fully operational. My analysis also concludes I should have turned back as soon as both engines wouldn’t accelerate to design speed!
Any thoughts on probable cause?
 
Topic said:
Help required! 13m tsmy with 2 x Perkins Sabre M225TI. Used regularly and extensively without a mechanical issue until family matters necessitated a two year stopover in La Rochelle. Lifted out in June 2017, bottom, rudders, props and shafts scraped and polished, new anti-fouling to hull. Local Perkins agents renewed ME wiring harnesses and serviced engines including fuel and oil filters and oil change. Gear test before departure all running fine. Part fuelled at Minimes on the way down channel enroute to Royan.

Open sea and discovered engines would accelerate to 1100rpm but no further ( max 2400). Continued down the coast and stbd engine died. After 10 mins restarted and noted erratic movement on flow meter. Died repeatedly but restarted after say 15 mins. Concerns over port engine increased anxiety. Weather deteriorated to NW F6 with 3m swells. Arrived late but safely in Royan.

My own analysis rules out electrical, injectors and filters so any thoughts would be helpful. Next leg is Biscay and can’t do that unless both engines fully operational. My analysis also concludes I should have turned back as soon as both engines wouldn’t accelerate to design speed!
Any thoughts on probable cause?
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Your own symptoms highly suggest to me this is a fuel problem. How did you rule out filters ?

I would be looking at the entire fuel line from tank pick up to the injection pump. There might be fine strainers in the fuel lift pump and even the injection pump.

It is interesting you have the same fault on two engines - both speed limiting. Have you taken a sample from the tanks ?

Will the engines reach full revs out of gear ?

Also check the issue that has been plaguing me recently - battery voltage to the stop solenoids. If this is low this could be causing the engines to stop.
 
superheat6k said:
Your own symptoms highly suggest to me this is a fuel problem. How did you rule out filters ?

Thanks for the suggestions and will definitely check fuel tank vents. I ruled out fuel filters as I changed out the two fuel filters on each engine one month ago and checked the two large racors btwn tank and engine and all clear. Believe that also rules out bacteria contamination as that would show in the racor. The fuel there was clean and 'sweet' smelling.

The engines easily spin up to full speed when not engaged in gear. I would suspect the transmission but for both to fail simultaneously?

Thanks again and appreciate further thoughts.
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The engines easily spin up to full speed when not engaged in gear. I would suspect the transmission but for both to fail simultaneously? Thanks again and appreciate further thoughts.[/QUOTE said:
Are the props fouled ?
You have not said how long it's been sat in a tidal river after its lift and service .Get a snorkel dive in and look ,report back ."June " ---- well to now Sept it must well fouled ??

Are you sure there's not an air leak ,they may rev up under NO load in N ,but need more diesel when in F and loaded .

It's either props or fuel restriction Or even both .
Easy to fix ,re visit all the work done on the fuel system -check its been done right , no leaks from double o rings


If the props are fouled ,it conks out due to excess exhaust gas temp due to overloading ,
If so then you should have turned back cos it would nt have done them any good overloading them
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Last edited:
sounds like one of:
Fuel Bug
A restriction on the fuel system crud blocking fuel pickups
Air being pulled in to fuel system
 
Thanks again. I am investigating air leaks or a fuel restriction. The props are fine. The yacht was hauled in June and scraped and repainted and something fouling both props just as I leave La Rochelle in good visibility is unlikely imho. Will report back when we are good to go! Meantime Royan seems very pleasant if the rain stops and the wind dies down!
 
Further update. Changed all fuel filters again including racors and replaced seals and O rings. Have ruled out tank vents by opening a tank hatch where the fuel retun lines discharge and then running both engines one at a time, both rev to 2200 clutch disengaged but max 1100 when engaged. Plenty of cooling water, oil pressure good and no smoke from either engine. Time for another think!
 
When I mentioned "fouled props " above I did not mean a rope. I mean,t a thin or thick growth of crustations etc .
From when you said they were last cleaned -June 17 .Then the boat sat until now .
Have you cleaned them since ? .
In the salty Med ( less agressive than Atlantic ) I clean mine every month ,yup 3-4 weeks of sat in a marina .
Your next move is grab a snorkel and take a look , if you can safely or hire a diver ,or another lift out or scrubbing mooring while the tide drops and boat if poss takes to ground ??
 
Portofino, thanks for that. Donned mask and swam under stern, but visibility is 5 cm! Shaft and props are covered in small, tip of finger size crustaceans! Amazing after just two and a half months since lift out. Hull clean as a whistle.

Obviously, this is not good and Euro 580 for a 24hr lift-out would solve that problem, but honestly not convinced the growth is enough to cause the engines to fail to accelerate beyond 1100 rpm. No smoke would say the engines are not overloaded. I am at a loss and have called in an engine mechanic for tomorrow.
 
since none mentioned the following, just throwing it in...

Looks like engines have turbos, with engines turned off, remove air filter and check if turbo shaft spins freely. Had that on mine due to crappy installation, one engine reved to 2.4K the other was stuck to 1.0-1.1K. Hope it's not that as refurbishing two turbos isn't cheap and you have to rethink the elbow.
any restriction due to prop fouling, stuck turbo, etc would create a decent smoke screen at the back :D

cheers

V.
 
Topic said:
Portofino, thanks for that. Donned mask and swam under stern, but visibility is 5 cm! Shaft and props are covered in small, tip of finger size crustaceans! Amazing after just two and a half months since lift out. Hull clean as a whistle.

Obviously, this is not good and Euro 580 for a 24hr lift-out would solve that problem, but honestly not convinced the growth is enough to cause the engines to fail to accelerate beyond 1100 rpm. No smoke would say the engines are not overloaded. I am at a loss and have called in an engine mechanic for tomorrow.
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You were lucky to get 5cm vis in the Gironde! Those barnacles will make a difference, but not to the extent of reducing revs by 50% You mention in the op that your ME wiring harness was replaced, what is that? If you're sure it's not fuel filters or air leaks then you need to look elsewhere, although I'd still be thinking fuel starvation. I would change all the filters just to eliminate that common problem. Can you be sure that the filters were actually changed when the service was done? Filters are cheap and easy to change. On my previous boat i had to change the fuel filters many times when I first bought it due to reduced revs and engine stopping. What micron Racor filters are you using? Are they too fine for a primary filter?
 
An interesting morning with the engineer on board. He checked all the filters again! Ruled out the minor prop fouling and checked both turbochargers and wastegate which all are performing as designed. Ran up to 2400 rpm both engines with clutches disengaged. Sea trial in F6 in the estuary, both engines will not exceed 1100 rpm. Returned to Royan, engineer is mistified and has gone for lunch!

On the wiring issue, in December last year whilst testing engines, the low oil pressure light alarm sounded on stbd enine and smoke emitted from the wiring harness which showed signs of melting back to the controller. Secodi, the Perkins agents in La Rochelle, renewed the entire harness and fully checked the port engine wiring.

This is our first sea passage since then....
 
longjohnsilver said:
How would they stop an engine?!
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Haven't read the whole thread, but isn't it a case of not revving in gear, rather than stopping an engine?

If so, fouled props will easily do that. When trouble shooting nay performance problem, always start with a clean hull and clean stern gear otherwise you can be chasing your tail looking for a problem that doesn't exist. The op know his props are fouled, yet continues to look elsewhere.
 
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