Dirty engine

How do you guy clean your engine? My thought is to just spray some heavy duty degreaser and just run the engine. Or get the engine warm spray some oven cleaner on it. I figure I will have to repeat a few times. I have a 92 25hp Evinrude tiller.

I wouldn't use oven cleaner. Try simple green, 409 or any of the orange citrus based degreasers.

If you have an orielys there, go get some B52. It is the best degreaser you will find. A gallon is $10. You mix it with water in a spray bottle, so it lasts a long time.

I wouldn't use oven cleaner. I've seen some of that stuff take paint off and corrode aluminum. A good degreaser and a steam cleaner or pressure washer /car wash will do wonders for cleaning. Just don't get the spray tip too close to the motor if you use a pressure washer.

I just cleaned my 25 Johnson that was pretty nasty . . .
as told to me by my mechanic for cleaning car motors....

I used Purple Power, sprayed it on the cold motor, let it set for 2 hours
then sprayed with water hose IN THE SUNSHINE ....
DO NOT turn the motor or actuate any of the electrical elements while wet.
If you have one, put the Leaf Blower to it like a hair dryer, that will eliminate water
from sitting in one place for too long.

IN THE SUNSHINE - all will dry out pretty quickly - the idea is a quick wash and QUICK DRY
without running the engine.

I'm sure any heavy duty degreaser will work. Purple Power is just my personal choice
for car and boat as it leaves no residue when washed off.
Vinegar will take care of any light corrosion the same way.

and my vote on Oven Cleaner or any caustic cleaner is NO NO NO NO NO !!!!

I often use WD 40,works great for me and is harmless on paint and engine parts

Kerosene works well. Many products today are mostly kerosene with fancy labels. Spray it on with a windex type bottle, let it sit, and use a bristle brush to loosen thicker gunk. Pressure wash the stuff off. Tip the engine up so the carb throat is pointed down; stuff a paper towel in the carb. This way nothing gets in and you can clean inside the mounting brackets too. One of those little electric pressure washers makes a good tool for getting the tight areas. That way I'm not flooding it with tons of water. Then I usually follow with a soapy household cleaner and same pressure wash. Grease ALL the grease fittings afterward.

Depends on what's on the engine.

Dirt/dust/mud bugs/etc the best I've used is ATV wash sold by liquid performance. Works excellent for dirt and mudbugs.

Grease/oil you'll want something a little stronger. Kerosene works well. Also B52, but it's strong stuff-don't leave it on for very long especially on bare aluminum. I use soem stuff at work that was supplied to us by some guy who jumped town, it doesn't have a name...it's yellow, looks and smells a little like pine-sol, but it works really good for degreasing mildly oily engines and doesn't hurt plastic, bare metals, or wiring. Ez-off will eat aluminum up and removes paint like nobody's business. Purple Power will too but nowhere near as fast as EZ-off will. I use ez-off on transmission cases that will get painted. It blackens the aluminum but removes ALL grease and paint.

Pressure washer is your friend. Stay away from the major ignition components. On a really nasty engine, I'll remove the ignitor/switchbox/power pack and some of the wiring to clean it. The Yamaha stuff (which is the only brand I'm familiar with) usually isn't that nasty, so a little ATV wash works on most of them. That said, I picked up a 15 hp 4 stroke tiller this past week that is COVERED with engine oil because the PO (I can think of more appropriate names but will keep 'em to myself) had it stored upside down in his shop. Cowling on the floor and foot sticking straight up in the air.

believe it or not, Dawn dish soap works wonders on oils, but doesn't cut into the really thick, tough grease very well.

+1 on Dawn. Cuts oil and rinses clean. It has replaced all hand cleaners and car wash soaps for me.