Hey guys,

I did a search and didn't find a thread about this. Im sure many of you have already seen this but I wanted your opinions on how this works and why this works.

http://www.rx7.com/techarticles_floodprev.html

Basically....

Rotary Engine Flooding Prevention


Any trip that is too short for the engine to reach normal operating temperature (needle in middle of temperature gauge indicates normal temperature) should follow these steps to prevent flooding of the engine.

With the engine already running,
Raise the engine speed to 3000 RPM for 10 seconds
Return to idle
Turn off engine
The above are instructions to prevent flooding as described in your Mazda Owner’s Manual. We have been using a slightly different method that does not require holding engine speed at 3000RPM for an extended period of time. Here are the instructions:

With engine already running,
Raise the engine speed to 3000RPM
Holding the engine speed at 3000RPM, turn the ignition key to the “off” position,
While simultaneously depressing the gas pedal all the way down.
After the engine has completely wound down, release the gas pedal.

 

I always use the second method, even if the car is up to temp.

 

Why does the second one work? Whats it doing?

Also, when you turn the key to the off position you gun it at the same time? WTF?

 

It makes sure every chamber is empty, because the engine will turn without any fuel getting injected I guess.
Also, 3000rpm is hardly 'gunning it'

 

Exactly, by increasing the revs to 3000 you burn up any residual fuel and because you switched off there is no more fuel being injected.

 

And, I'd guess that the wide open throttle w/ ignition off ventilates, and eliminates any remaining fuel from, the combustion chamber/rotor.

 

Very interesting. Since flooding has not been an issue for me ever since my 2nd gen days, are there any other possible benefits to this like perhaps cleaning the plugs / engine cleaner?? (When I want to clean those I use a slightly higher RPM )

Edit: Why the hell did I click on FL? Oh well...

 

Clean the plugs, you must be thinking if the "Italian tune up," i.e. revving the ***** off your car to get rid of the carbon build up

 

If you keep the carbon build-up out of your engine and change the plugs every 12k, you wont have to worry about flooding. Preventive maintenance goes a long way. Oh don't granny drive the car soo damn much.

 

Partially true. Revving only helps reduce build-up. It does nothing for the carbon that's already built up. Built up carbon needs to be chemically cleaned out. I clean mine twice a year. Once done, revving will help keep from building back up.

 

What do you use to chemically clean the carbon out?

 

"While simultaneously depressing the gas pedal all the way down. " This is gunning it no? While the engine is of I guess.

Also, good question about cleaning out the carbon. Sounds like a PITA to do .

Premixing should help with the build up right?

 

In all the years I've had almost 2 dozen rotaries, I never ever had to chemically remove carbon from my personal vehicle. Frequent maintanance and hard driving is my style, so I guess that helps a lot. But I'm not saying you shouldn't do it, it's probably good done right. As everyone knows, automatics and granny driven ones foul up, and I've come across plenty of those. I've even set an FD completely on fire for a few seconds when the ATF came shooting out of an exhaust leak right by the turbo LOL....

 

once the tank is close to empty use seafoam and a 1/4 tank of gas. drive in higher rpm range to break up the carbon and you will have a clean happy engine

 

Sorry for the dumb question but which brand seafoam do you recommend?

 

Uhm... Seafoam brand?

http://www.seafoamsales.com/

I've never used that stuff and don't think I will but I hear a lot of good about it. At least make sure if you do it that you read the instructions. Good luck.

 

2nd gen guys have been doing stuff like this for years... this or a fuel cut switch.

if you ditch the stock ECU you should never have flooding problems as long as you have clean injectors and good compression

 

so there's actually a function for our cars to rev and shut down the car .... nice!