model is SSO25; removed back panel and it says leslie tremolo unit model 17L-2S

If the organ was not plugged in or not turned on at while the footpedals were submerged, you should be fine. Contrary to what most people think, water does not usually cause any permanent damage to the actual electronics, although salt water is another issue - but sometimes still can be saved.

You do have to take them apart to allow them to thoroughly dry out. If there is crud on them inside from the water, use some windex on a toothbrush to clean it off. The use clear water on a toothbrush to rinse it off. Dry off and let air dry again. Sometimes placing them with a fan blowing in will help - maybe even a hair dryer for spots.

If there are controls or switches involved, they too can be cleaned up but sometimes require compressed air to get the water out. They then need a contact cleaner with a light lubricant lightly sprayed in them.

organ was plugged in while under water for short period of time., but one prong was broken while being unplugged, so cannot even try now. concerned about foot pedals though

"If there is crud on them inside from the water, use some windex on a toothbrush to clean it off. "

Isopropyl alcohol is used by many manufacturers to 'wash' electronics.

Submerge, swish around, shake off excess, allow to dry.

The 90% is better than the medical 70%.

"Isopropyl alcohol is used by many manufacturers to 'wash' electronics."

With all due respect, brickeye, cleaning of wave soldered printed circuit boards with chlorinated hydrocarbons and alcohol fell out of favor in the 1980's.

Environmental concerns about VOCs and the use of surface mount components, required new manufacturing requirements. Circuit boards for the last 20-30 years are wave soldered using no-clean or water-clean fluxes, although cleaning is almost always done.

The most common cleaning agent is deionized water heated to around 130-140 degrees. People sometimes wonder why you see deionized water trucks running around Silicon Valley all the time.

Some specialized military/space manufacturing may spec for VOC based fluxes and have very specific cleaners used after soldering.

Getting back to the problem at hand, you don't want to dip unknown comonents into alcohol - it can disolve lacquers, glues, and laminates.

It also will not clean water based contaminates such as Coke, coffee, or things found in a flood. The technique I described has been used for years with excellent results.

"With all due respect, brickeye, cleaning of wave soldered printed circuit boards with chlorinated hydrocarbons and alcohol fell out of favor in the 1980's.

Isopropyl alcohol (C3H8O) is not a chlorinated hydrocarbon.

It is one of the replacements for the chlorinated hydrocarbons, and continues in use (especially in areas of the world that are not panicked by alcohols).

It remains a good method for a small issue like this.

This is not an industrial scale activity.

DI water is only useful with soluble contaminants unless you use a LOT of agitation or ultrasonic cleaning.

The electronics industry (especially in the US) has spent a lot of money on water soluble fluxes to allow DI water to be used. It still has problems getting under some larger components unless a wetting agent is added.

The OP is not trying to remove flux, but contaminants carried in by the water.