How do I clean an oily engine?

mrmac

Cadet
Joined
Dec 2, 2005
Messages
10
Our sailboat?s diesel engine pretty much fills the engine compartment. The engine is oily (probably due to my overfilling the crankcase) as are the sides of the compartment. Reaching all offending surfaces to wipe down w/ rags isn?t possible.

Looking at others' suggestions I find varied ideas about how I should clean up everything.

The general idea seems to be to spray the area with:

One of these
Simple Green
WD-40
Citrus product of some kind

Then
Pressure wash everything (or)
Use an air compressor to remove residue

There seems to be a strong possibility that I will make matters worse which raises the following questions:

What needs to be covered on the engine before starting?

Would I be better off to wait until the boat is hauled in the late fall rather than to do this now or does the risk of possible fire outweigh other concerns?

My current thinking goes something like this:
Cover the alternator and air breather w/ plastic bags and my eyes with goggles.
Put many oil absorbing pads under the engine.
Spray the engine and compartment with an orange citrus product.
Allow that to sit for a few minutes, but use an air compressor to remove the resulting mess off the engine and compartment walls while everything is still wet.
Safely dispose of the dirty pads.

I am quite open to suggestions!

Thanks,
Mrmac
 

SnappingTurtle

Lieutenant
Joined
May 4, 2008
Messages
1,251
Re: How do I clean an oily engine?

I like to clean oil with oil, or better said I generally use WD40. I take my time and it is a mess, but once it is done, it only takes a little time invested on a regular basis to keep it that way.

I don't like to use water, water based products, or high water pressure on anything to do with motors or electrics. Pressurized water works fast, but tends to push grit and grim in places were it shouldn't be.

That said there are companies that use pressurized steam to professionally clean motorized equipment. If it was mine and it had been neglected for a long time, I might think about using one of these professional companies. It cost a little (but often less than doing it yourself when all things needed are added up), they know what they are doing, and it will come back looking new.

On the other hand oily, greasy things don't rust, or corrode, and I have seen people that have used equipment non-stop for decades without a problem, and one day decide to clean it, the next day things start to go bad.

It is your choice, I just try to do a little at a time and it never is a big job. Each time I touch a motor, I leave it a little cleaner than it was before.
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: How do I clean an oily engine?

I always used GUNK, followed by pressure wash, on my car diesel engines.
 

mrmac

Cadet
Joined
Dec 2, 2005
Messages
10
Re: How do I clean an oily engine?

I purchased a can of Gunk yesterday, but the instructions on the can said something about covering the wires, and all of it had to be washed off before starting the engine because of possible fire. Since I can?t wash down the engine while the boat is in the water, I?ll give the WD-40 a try, doing small areas at a time. When I have her hauled, I?ll do a more thorough cleaning.

Anything else that I should be watching out for?

Thanks,
Mrmac
 

SnappingTurtle

Lieutenant
Joined
May 4, 2008
Messages
1,251
Re: How do I clean an oily engine?

Work from the top down, and concentrate on one component a time. You will be surprised how fast it will go. If you get tired save some for another time. It took a long time I am sure to get to the condition it is in now, and it really doesn't matter if you do it all at once, or a little at a time.

For me working on a clean engine is a lot more enjoyable than a dirty one. It is also much easier to trace down small problems before they become big ones if you do it on a regular basis. It is just not as intimidating to work on a motor, if you have already touched every part a dozen times before.

You should also try “Simple Green” All Purpose Cleaner/Degreaser. I have used it for at least 30 years on my bikes, and it has none of the negative side effects of some of the other products on the market. Here is a link to a independent test. http://www.totalmotorcycle.com/reviews/SimpleGreenAutomotiveReview.htm

Have fun and enjoy having a clean motor! :)
 

mrmac

Cadet
Joined
Dec 2, 2005
Messages
10
Re: How do I clean an oily engine?

I had cleaned the engine (somewhat) and put new oil absorbing pads under it. There was almost no wind so we ended up running the engine (Yanmar 8) for a total of about 10 hours during the last 2 days. The new pads looked as though someone had taken a can of spray oil and emptied it on the pads and throughout. In total it wasn't a lot by volume, but it sure was a mess - the level in the crankcase hadn't dropped appreciably (and it wasn't milky). I'm also getting some soot in the exhaust.

I realize that this is NOT the engine thread, but I didn't see an appropriate one - mostly outboard stuff.

Thanks,
mrmac
 

Whoopbass

Senior Chief Petty Officer
Joined
Jun 29, 2006
Messages
653
Re: How do I clean an oily engine?

I have been cleaning outboards with oven cleaner. It sure works better then engine cleaner. I pressure wash it after it sits awhile and it comes out spotless. I buy the cheap stuff at the dollar store.
I haven't seen any side affects as of yet.
 
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