Re: The mystery oil slick in exhaust


If you were looking at motor oil in the exhaust you would see a fairly rapid loss of oil level in the crankcase, and likely a LOT of smoke. 

I'll second Ian's suggestion that what you are seeing is actually diesel fuel.  You mention a bit of smoke also, and that would back up that suggestion.  One (or more!) injectors are either sticking open, or have a bad spray pattern and the fuel is not fully burning.  If this is happening a LOT you can actually see an increase in the level of oil in the crankcase as it gets diluted with diesel fuel.  This would be VERY bad.

You might be able to narrow it down to which cylinder by cracking the nut holding the fuel line to each injector in turn while the engine is idling.  When you open the fuel line to a "good" cylinder, the engine will slow and run rougher.  A "bad" cylinder will show little or no change.  It could be more than one.  Injectors can be damaged by dirt, or water in the fuel, so there could be a common cause.

This is important to get fixed.  When a cylinder wall is wet with unburned diesel fuel the lubricating oil is washed off, and wear is greatly accelerated.  Cleaning/Testing/Repairing/Rebuilding injectors can be done, but it is rather specialized work requiring high precision tools and expensive test beds to do correctly.  Not the job for the island mechanic, even if he thinks he can.  

If you do replace them with new, save the old and have them rebuilt by a specialist shop when you can.  Spare injectors are not a bad thing to have!

Bill Kinney
SM160, Harmonie
Rock Sound, Eleuthera, Bahamas

---In amelyachtowners@..., <parkianj@...> wrote :

When I had the engine mounts replaced and other work done on the engine in Martinique, the Amel engineer started it and told me I would either need to clean the injectors or preferably put in new ones (but not out here! They’re too expensive. Get them in Europe). Reason = he said look at the exhaust, there are traces of diesel coming out with the water - dirty injectors.

It would be worth verifying this, either from other owners with more experience or an engineer. My Perkins has done 5,500 miles now.


Ocean Hobo SN 96 Antigua.

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