Chocolate coloured engine oil (4 Stroke EFI 50hp outboard)

White smoke is usually unburned fuel in my experience. If my EMDs idle 4 or 5 hours, I'll fog up a half square mile of sea for 10 minutes when I throttle up.

 

Wet exhausts and underwater exhaust will make steam. There is no way to tell if the water is coming from a gasket leak

 

Gonzo me mate.

Sorry I am not conversant with outboards and I am only surmising that like a standard engine the head gasket seals the cylinder between the head and the crankcase as well as sealing the water between the head and the crancase as the head is water cooled and seals the same for the oil passage to luricate the cam shaft and push rods.

A faulty head gasket can cause a flow from one to the other.

In my opinion water in the oil has left it the wrong colour, chocolate brown indicates to me worn piston rings and burning the oil lubricating the cylinder, which will eventually burn all of the oil in the crankcase.

Poida

 

you are talking about diesels not petrol.

 

you are talking about inboard risers. he has a 50 hp outboard.

 

the more you type the more obvious your lack of mechanical knowledge .you can have light chocolate oil if the water ingression is not to bad. the more water the creamier the color.
gonzo is correct . water leaks into sump across galleries is quite common and has no effect on compression. being an outboard it most likely will be the head gasket because the block does not hold water when stored.or it may just be condensation considering there is only a small amount of water in the oil.

 

Your nose will tell if the "white smoke" is steam or unburned diesel in the exhaust gases.

 

An increasing amount of "steam smoke" could be an indication.

 

Thank you for your input Whitepointer.

I am a mechanical fitter
Your post to me and your reply to Yobarnacle I will take as a joke so as not to embarrass you too much to other readers.

Poida

 

Correct! I don't use petrol on boats. Even our portable pumps are diesel. Petrol is a hazard easily avoided by simply not having any aboard.

I know, a lot of folks use petrol outboards.

I don't like them.

Many folks like outboards , I think, because they want to go fast! They should get an airplane.

My opinion is, any boat that can go faster than 25 kts, should be required by law to have BRAKES!

 

i was referring to your comment about white smoke which is true for diesel but not petrol.

 

are you serious. you might be a fitter but you have no engine experience. more likely changing bearings on conveyors or repairing fixed plant. if you think my post was a joke then it just reinforces your lack of engine experience.

 

I know you were. I'm pretty ignorant about outboard motors.
Didn't know that fuel rich petrol engines didn't make white smoke.

Guess I do now. thanks.

 

if a petrol runs to rich it will normally misfire on 1 or more cylinders due to wet plugs. being an efi i doubt if he has any issues with fuelling anyway. black tail pipes were a sign of a rich mixture on earlier cars and a tan tailpipe was an indication that the mixture was good.

 

Thanks. Just checked my truck. 18 year old dodge van. 318 V8. EFI. Inside of exhaust pipe black with carbon. Needs tune up I guess.
learning every day. thanks