Cleaning a diesel engine

[DannyS]

We'll be putting our boat up for sale this spring and I have some items I'd like to take care of in order to make the boat look its best, cleaning the engine and engine room is on the list. Mainly, it's belt dust that is the issue. Last year, I realigned the alternator belt but never got to the cleaning. Is Gunk the preferred method followed by a freshwater rinse? I've never washed down an engine, is there anything that should be masked off or removed before doing this? I imagine sealing off the air intake is pretty critical, but what else?

 

[Rich Stidger]

DISCLAIMER: I have never cleaned my engine as I describe below except in small areas to prepare for rust prevention and repainting. But if I were to clean the entire engine, this is what I would do.

Cover the alternator and any electrical connectors. The lugs and terminals on the starter and sensors are OK I think- at least I wouldn't cover them. Cover any engine openings in addition to the air intake.
I would use a non-volital Gunk-type de-greaser/cleaner in a spray bottle to direct the cleaner to the dusty and greasy areas. After letting it do it's work, I would rinse with hot water using a garden sprayer. Use a shop vac to suck out the pan under the engine. Rinse and repeat. Use the shop vac to suck out any standing water in any engine pockets. Then immediately start and run the engine up to full temperature for 20-30 minutes. That should evaporate any moisture left on the engine.

The last time I cleaned belt dust, I just wiped all the surfaces down with several rags moistened with a general purpose cleaner. The results weren't perfect, but acceptable.

 

[Tally Ho]

+1 on covering the alternator.

i cleaned mine over the winter when I had no water hose available...I sprayed it down with some engine cleaner, staying away from the alternator, and then “rinsed“ it down with some water in a weed sprayer. Minimal water.

Worked fine and got rid of the hose dust, which was most of the issue

Greg

 

[CrispyCringle]

I use Scrubbing Bubbles spray bathroom cleaner (yellow cap) on my cars. Works very well. Spray on, let set a few min and rinse off. Kind of has an Armor-All look when finished. As mentioned, cover electronics, and I never use pressure to rinse off. Just a low pressure stream of water.