Engine help (divemaster1)

Whitelighter

Well-Known Member
Joined
4 Apr 2005
Messages
13,977
Location
Looking out of the window
Visit site
Overnight to Mallorca we ran at slow speed.
At first light noticed starboard engine kicking out lots of black smoke (I’m guessing unburnt fuel).
Tried to pop her up onto the plan but she won’t do it. Port engine tries but the starboard just isn’t having it.
Hull is clean, was jetwashed 48 hours ago.

I’m guessing a stuck/failed turbo?

Engines are Detroit 6V92
 
Sorry to hear about this , I would have thought overfueling from a stuck injector over a turbo problem .
If black smoke appears at D speed .
There’s all sorts of reasons why they fail , poor filtration , water ,and agglomeration from low EGT ,s .+ plain age as well .
Let’s just hope a local tech can remove and service them , perhaps replace the odd one(s) ?

Worth checking the oil levels ( blue smoke ) to eliminate that and checking for blow by - remove the filler cap while it’s running and compare pressure on the palm of your hand with the asymptomatic engine .

Good luck with a rapid fix .
 
Check the emergency air flap hasn’t been triggered, centre top of engine. Normally if triggered would shit engine down but may be partially closed
 
6v92 being a two Stoke has an emergency shit down airflap just in case of a run away engine . You should see it in front of turbos. There is a lever on the side, if it has been activated you twist lever until it latches open again.
 
6v92 being a two Stoke has an emergency shit down airflap just in case of a run away engine . You should see it in front of turbos. There is a lever on the side, if it has been activated you twist lever until it latches open again.

Once caught the lever with the back of my trousers when working on 8V92's. Just couldn't work out why the bugger wouldn't start. Mechanic came down, flipped the lever, and was gone in 2 minutes. Felt such a fool.
 
Lever is on side of flap on the engine, surprised there is nothing at helm, not even a covered push button ?
 
J.,

Should be fairly easy to remove the air filter and with the engine shut, try with a finger to spin the turbo blades, no?
Is it the first real run of the boat since last season?
If not, I very much doubt it's the turbo...

V
 
Why would the “ valve “ spontaneously close ? Anybody.
Jez,s first post inference was the black smoke came at D and also he feels it’s wont plane transfer the P .
Suppose a long time at D the rings never heat up and seal as much as P .So minor combustion products get past and maybe via the crank case management of the excess fumes , 8hit gets redirected into the air supply pre turbo and eventually “ gums “ up the vanes of the turbo blades ? Is that what the “ stuck turbo” contingent “ are suggesting??

Nah .Its an injector issue that’s where my money is .

Even @ D speed the turbos free wheel or have something like 0.1 or 0.2 bar boost , from around somewhere between 1.6/1.8 at P speed .

A bearing in the turbo is another matter , too long at D inadequate oil pressure or aged oil .Jez has not said anything about the hrs or importantly time between the last lub change.Or the quality of oil at the last lub change .
DD ,s are oil sensitive single weight .

Needs further investigation.
 
Last edited:
Top