carb fogging

[c21fishing]

what is the best way to fogg the carbs on a 89 70 hp evinrude . i have 3 carbs correct .do i spray in each one indiviually until the motor dies or just back and forth to each carb .

 

[oldcatamount]

Re: carb fogging

Empty fuel lines and carburetors
While the engine is still running, disconnect the fuel line from the engine. When the engine dies, the fuel delivery components will be empty, preventing gums from forming in the stagnant gasoline and clogging lines and jets or injectors.

Fog the carburetor intake(s)
Before the engine runs out of fuel, spray fogging oil into the carburetor(s). Fogging oil is an anticorrosive that will protect the internal surfaces of the carburetor and the cylinders. Typically the engine will run rough just before it runs out of fuel. As that happens, give the carburetor(s) a heavier shot of fogging oil to make sure internal surfaces are fully coated.

 

[Daviet]

Re: carb fogging

On an engine with multiple carbs you don't want to run it out of gas, one carb will always run out of gas first. The other cylinders will have fuel and keep the engine running. The one that ran out of fuel now has no oil in the cylinder.
I normally warm the engine up and run it at a fast idle, fog all carbs, moving quickly from one to another, when the smoke is really rolling have some turn off the key. Then drain each carb of fuel.
Or you can mix up one gallon of gas with a very heavy mixture of oil and run the engine on it and then drain carbs. I am sure other have various ways of doing it and will give their suggestions.

 

[Vic.S]

Re: carb fogging

Not wishing to hijack the thread but last year, when I could not get any fogging oil from my local guy he suggested spraying in 2 stroke oil .

I did that and again just done it this year. (I used a trigger spay bottle although he suggested an oil can)

Any comments. Sensible or any reason why it is not such a good idea?

 

[robert graham]

Re: carb fogging

Vic.S, seems like a pretty darn good idea to me, especially if you can't get your hands on some real fogging oil. I imagine the fogging oil has some type of corrosion inhibitors in it, but the outboard oil would definitely coat all those shiny internal surfaces with an oily film. Pretty "slick" idea!

 

[Daviet]

Re: carb fogging

When I worked on the gulf we had a special one gallon gas tank just for fogging engines. It had a gallon of gas, four times the normal amount of oil and 1/2 pint of automatic transmission fluid ( not the ford type ). Would get the engine running on the regular tank and then switch to the fogging tank, and man would it fog.
I guess what I am saying is that I don't think the type of oil that is used is of much concern as long there is a lot of it there.

 

[beverly]

Re: carb fogging

if 2 cycle and fogging oil is good to use. What about ATF? or is that too much cleaning power.

Oops, didn't see that last post.

 

[surrender]

Re: carb fogging

Why fog, just used the boat all year long and enjoy. J/K but is the fogging for storage reasons? Seems a little early to think about winter storage in most places.

 

[askmelater]

Re: carb fogging

what is the best way to fogg the carbs on a 89 70 hp evinrude . i have 3 carbs correct .do i spray in each one indiviually until the motor dies or just back and forth to each carb .

I would spray into the carbs between all of them quickly and get all the smoke to clear then blast it one more time real quick and turn it off.

If it's going to be for a long-time.... take the spark plugs out and spray some in the cylinders. Turn it over manually to spread it all around. Put plugs in and you're good to go.

I wouldn't drain the gas. I've been told to treat the gas if needed but don't let the motor sit their dry - the gaskets like a little moisture so they don't dry out.

$.02

 

[d.boat]

Re: carb fogging

I have no idea if the alternative suggestions (TCW3, ATF, etc.) are as good, better or worse than "real" fogging oil. However, I think fogging oil is designed to be more "clingy" to stay on the metal surfaces and probably has additives to inhibit corrosion. That said, if I couldn't find it, I'd probably use the alternatives. But, if you can find it locally, why would you use something else rather than something actually designed for the purpose and recommended by the engine manufacturers?

The procedure I use, which I think is the correct one is:

Put stabilizer in fuel

Run engine long enough so you're sure that the stabilized fuel is in all parts of the fuel system up to and including the fuel lines, filters, carbs, etc. Make sure this is the case for all your fuel tanks if you have multiple tanks. I cruise 15 minutes on one tank, switch tanks and cruise home.

Idle engine and liberally spray into each carb intake, quickly switching between them (I have 6 so I dual-hand it w/ two cans!). With my V6's I spray until a whole can has been used. With my little kickers, I just spray until it is smoking like crazy.

Turn off engine. You're done... or you can remove the spark plugs, spray a liberal amount into each cylinder, rotate the engine a couple of times (not running) and put the spark plugs back in.

Do not run multiple carb. engines dry for the reason explained above. If you must empty the carbs, drain them.

I don't drain carbs. It has been told to me by credible people that if the bowls and tiny passages in the carbs are flooded with stabilized gas, they will not gum up. I've never had a problem doing it this way for 4-6 month storage periods. If I knew it was going to be longer, I'd probably drain the carbs, it's not that big of a deal to do it.

I used to let my single carb'd kickers run dry but it really is a trick fogging through the carb and letting them run out of gas because the fogging oil tends to also bog the engine so you really don't know if it's quit because it's run out of gas or bogged by the fogging oil. You could be leaving gasoline in the carbs to dry out or gum up.

So I just run stabilized fuel and fog my kickers just like my main engine.

There ya go, the only right way to do it!

 

[Dhadley]

Re: carb fogging

C21, tell us what you're trying to do. You mention "fogging" the carbs but most of us assume you're trying to fog the motor. Are you trying to clean the carbs or prepare them for storage?