Water injection treatment for all rotary engines?
 

hey just wanted to know how many have tried this method? whats he pros and cons to doing this?

i got this from the rotary resurrection site

Water injection treatment for all rotary engines

When talking about rotary engines, carbon buildup is a common problem brought up. I have a writeup elsewhere in the tech section of internal engine damage pics, showing the effects of carbon buildup. A good way to combat this harmful effect is to inject water into a running engine as a matter of maintenance (note that I am not referring to water injection as a method to assist tuning and combat detonation). By allowing an idling engine to injest a small amount of water, it hits the rotor faces and turns to steam, cleaning off carbon as it does. The more regularly you perform the maintenance, the cleaner your engine will remain. The procedure (I believe) was originally brought to light by Rob @ Pineapple racing, so please note that I’m not trying to take credit for this, only spreading the information for use by individuals.

Note that this should in no way harm an engine in good health. Water doesn’t combust, but it doesn’t harm any internals or sensors such as plugs or 02 sensors either. The engine will misfire and stumble during the time water is injected, this is normal. You will have to apply throttle to keep the engine above 3000rpm during the injection.

To perform this, I use a gallon jug of water and a long vacuum hose, say 3 feet. Though this is different for nearly every year and model, the underlying goal is to find 1 or 2 vacuum nipples on the intake manifolds after throttle body, preferably on the lower intake manifold so that the water can run straight down into the block. You want to feed both front and rear rotors evenly…generally you have 4 intake runners, 2 for the front, 2 for the back. Some engines have one nipple that can feed both (s4 turbos, for example, have one above the BAC valve that is evenly split between F and R primary runners). Some engines (fd’s and s5 na’s for example) have 2 separate nipples that can be teed together externally (vacuum hose and tee) to evenly feed both rotors.

With the engine running, remove the vacuum cap or lines that used to cover the nipple you’re using. You might have to apply throttle, so the engine doesn’t die due to a vacuum leak. Insert your hose(s) onto the nipples, and bend the hose somewhere in the middle by hand so that it seals off the air intake. Now, dip the end of the hose into the water at the bottom of the jug. Either grab the throttle linkage and rev the engine up, or have an assistant hold the throttle for you, above 3500 or so. Release your crimp on the hose, letting the engine vacuum suck water in. The engine will begin to shake and misfire, apply throttle as necessary to hold 3-4krpm and keep the engine from dying.

Expect a lot of steam from the exhaust. This is normal. I let the engine drink the whole gallon at once. When it’s done, it’ll begin to clear up slowly, and you can gradually let off the throttle and replace the original vacuum hoses/caps.

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I did this to a rebuilt engine...scary

I did this to an FD that had been sitting for a long while. It had only been started and moved maybe 50 feet at a time for many months (the owner was deployed). One day it seemed to develop a stuck side seal......after using this treatment the problem cleared right up, and this was only after maybe 12 ounces of water.

goodfella,

which vac lines did you use? did you use one or tee two?

used one of the small nipples on the pass side of the uim, where you would typically have a boost guage hooked up.

so just one?

I've done it. Just one nipple. I did it at night and the turbos glowed as brightly as after a long full-boost drive. I wasn't thrilled about DOING it, but it has cleared up some general "running rough" problems. I generally find an ATF treatment to help the car more than a steam cleaning.

Rotary Resurrection is on the Forum. You can always ask him more questions directly.

If this is the case I would strongly reccomend everyone with a turbo idle it for a good 10mins to let the turbos cool down. Just so the oil doesn't heat soak and turn into carbon.. Not good for your turbos on next start up, hehe..

i think im going to try this today.. i haven't ran my car at all threw the cold season so maybe this will clear up some of the idle sputter problems its having...