What is the longest you can wait to safely flush your engines after a day of use?

the sooner the better, but as long as you et it done that night or the next morning you are fine, some people wait a week or so but I think that is way to long. Even if you are going to leave it the water for a few days in a row I like to flush it every evening at that dock. Just tilt the drives up and put the muffs on then lower the drive and run em on the hose.

Bob and his crew are totally against the use of "off the shelf" engine oil flushes as they can loosen large chunks of particulate matter that can clog screens etc.

They say to use this product if you have a deposit ridden engine and it may take a couple treatments.

One of the benefits of synthetic oil is the amount of deposits is drastically reduced..another reason to use it from day one.

You guys really keep me on my toes these days.

http://www.auto-rx.com/

Hydro, not oil flushing... I'm talking about fresh water flushing.
Anyone use desalination additives to flush?

Sutphen30, so you think my JC motor can wait a day or two till it gets flushed out??? or should I carry extra duct tape.

I always flush once I get back, but as i've noted on the GD forum, my neighbors wont like it if i run it when i get back late at night. So if it could wait till the next day that would help alot.

I always flush with dawn or boat soap at the end of the weekend, so it sits for 2-3 days as is. Less corrosion will occur in the wet system than will occur as it dries out. Internals look good, even the Lightning headers only show light corrosion.

insptech, do you just flush at the end of the weekend w/ soap, or do you also flush after every use?
And what does the soap do?

I usually flush at the end of the weekend. I have a friend that has all his work done by Art Lilly and the soap deal was what Art told him to do. His engines looked perfect after every season, even the aluminum heads, so I figured the soap was a good idea. The soap will break the salt loose from the passages better than just water. It also leaves a light coating inside which should help prevent corrosion. As a test try rinsing down the boat and then drying with no soap-you will find salt deposits after it dries. Just a little soap in the rinse water and no more salt. And a lemony fresh exhaust is just an added benefit

I do it * EVERY * time out, as soon as I get back to the dock. Run 'er on the hose about 15min per side. No soap, just fresh water.
I have given up caring about the noise, as I rarely get in after dark. * EXCEPTION * - Last year, after the 07/04/'04 fireworks ( Fourth of July ), I waited until the next day, because I wasn't moored until probably 1130PDT.
There ARE overnighters at my marina.
Anyways - so far, so good with my method. Maybe I will integrate something like Simple Green into my flushing regimen.

Bottom line: Don't wait ANY LONGER than absolutely necessary. Oxidation mostly occurs when a previously 'wet' surface becomes a 'dry' surface.

It's basically, the sooner the better. I wouldn't fire it up late at night, just wait until the morning. I use soap too when flushing. I don't know if it does anything or not, but it makes me feel better. Also, when the bubbles stop, you know it's fully flushed. I just squirt some Dawn in the hose before connecting it.