There is an awful long amount of time where there is no intake or exhaust port for fuel to evaporate out through. It depends on the location of the rotor face.

 

Keech, I wish I had the technical answer for this one but I don't. The sparkplugs sometimes get ruined and will not do their job, refusing to be revived. A fresh set makes a huge difference.
One of the problems that the RX-8 had was; and I mentioned this previously, that with a weak enough battery the management goes into a mode where the throttle will not go beyond a certain opening angle (might have been 25%). This creates two problems : Ideally any flooded engine, piston or rotary, benefits from having a wide open throttle. This provides the needed volume of air that can help evacuate the chambers. The second problem is that I'm not sure if the fuel defeat feature is operational if the throttle does not actually physically achieve full opening. Maybe this could already have been addressed with the latest computer upgrade (re-flash). Who knows?

 

If a weak battery is the reason for a lot of flooding could this be the answer?

http://batterytender.com/default.php...a75649dd9b4eee

 

With regards to the flooding issue and replacing the plugs, piston vs. rotary engine.

First, maybe a model A Ford would need to be opened up due to a severe flooding issue; however, today's piston engines WILL NOT flood to an extreme where they would have to be opened. They are configured in such a way that once the fuel is discontinued to the piston chamber, i.e., by disconnecting the injector fuse or by manipulating the carb on the older models, the unburnt fuel with be discharged through the exhaust valves due to the combustion. This leads me to my second point, the combustion loss that the rotary engine experiences is not to be compared to a piston engine. It is not established in the same manner; therefore, cannot be lost in the same manner. The seal shape and make up inside the rotary engine yields it's ability to lose combustion easier then the piston engine.

I agree with the previous statement about the ability to clean the plugs instead of replacing them, a costly savings. However, I think you need to inspect them everytime you experience a flooding issue with the 8. My reasoning, if your vehicle floods and you are able to get it started, the unburnt fuel/oil mixture that the plugs have been bathing in will get burned onto the plugs and cause them to foul. A simple-layman explaination.

I have dealt with my wife's vehicle flooding in the past and have explained to her how to operate the vehicle to curb the posibility of this happening again. Thus far she hasn't experienced any problems. Just remember. Anytime you start the rotary engine, allow the engine to reach normal operating temperature before it is turned off and you will not experience any problems.

 

[QUOTE]Originally posted by tgarland855
[B]With regards to the flooding issue and replacing the plugs, piston vs. rotary engine.

>... the combustion loss that the rotary engine experiences is not to be compared to a piston engine. It is not established in the same manner; therefore, cannot be lost in the same manner. The seal shape and make up inside the rotary engine yields it's ability to lose combustion easier then the piston engine.

Very interesting. Can anyone explain why this is so? What it is about the seal shape or whatever that makes this so much more of a problem with a rotary than with a piston engine ?

>I agree with the previous statement about the ability to clean the plugs instead of replacing them, a costly savings. However, I think you need to inspect them everytime you experience a flooding issue with the 8. My reasoning, if your vehicle floods and you are able to get it started, the unburnt fuel/oil mixture that the plugs have been bathing in will get burned onto the plugs and cause them to foul.

I am aware that the rotary normally uses oil much faster than a piston engine. Is much oil getting into the combustion chamber? Could this, rather than the gasoline, account for the need to clean or change plugs after a flooding?

 

well yeah, oil is purposefully metered (sort of "injected", but at a very very slow, runny drip kinda thing) into the motor to lubricate the apex seals of the rotor. no, very very little oil is actually getting into the motor these days in the 13B-MSP, compared to some of the first rotaries where there was an oil drip down from the carb into the motor.

there isn't that much oil ever going into the motor (in regular operation, obviously) and is burned away rather cleanly during combustion.
when you flood the motor, there ends up being a lot of condensed gasoline puddled in the motor, and as you try to push it out the exhaust ports (turning it over) gas is going to nicely coat the sparkplugs. as you probably know, gasoline is a hydrocarbon, meaning it's a non-polar organic molecule (oil's the same type of dealie). this sort of compound won't conduct, and so crudded up sparkplugs won't spark (or if they can, it takes an enormous drain in order to).

cleaning off the plugs is a good (an necessary) way to remove this resistance. replacing these plugs is a good (and unnecessary) way for the dealer to gouge profits. there's no electrode to gap on these rotary style plugs, so cleaning (even with a wire brush) isn't often going to ruin the plugs, is really easy to do, and is a much better option compared to replacing the plugs (OH!! unless you're going from the cold plugs to the new hotter spec plugs... if you have an old car, as the new ones already have these spec plugs).

 

This was all really interesting. More questions: exactly what causes the carbon depositions on the plugs? Why is one episode of flooding enough to create such deposits when and engine can go through billions of cycles before the plugs need replacement? Unlike oil, I think of gasoline as too volatile to stick to the plugs long enough to get carbonized on, but if there's hardly any oil, that wouldn't make sense to me either. Thanks again.

 

I have started and stopped the engine without waiting and haven't had a problem. I have also started the engine once and turned it off by accident but still had no problem.

However when i stop the engine I rev it up to 4.000 and turn off the key. I like the way it sounds

 

Some say that rev'ing the engine before turning it off will use excess fuel, but doesn't rev'ing the engine, stepping on the gas, actually create a situation where more fuel is going to the engine? And then shutting it off all of a sudden, wouldn't that cause a flooding scenario?

 

No, because the motor spins fro several seconds after you shut off the ignition. During that time the injectors are off sending no fuel to the motor. So basically the motor spins without getting any fuels. The theory being that the fuel is then expelled out the exhaust

 

I have also started/stopped my RX-8 on at least two occasions without a problem and I do not rev my engine before cutoff. Unfortunately, so little is know about the phenomena that I believe having successfully done a "short trip" doesn't prove anything, one way or the other.

I believe that the best thing to do to insure against flooding is to let the engine always warm up per the Mazda warning.

 

Have had my Sunlight Silver AT RX-8 for about a month. Moved parking spaces in my driveway. The next morning, car wouldn't start. Was told the engine got flooded. Plugs got fouled. Had to replace plugs to restart.

 

My RX8 got flooded yesterday. Thanks to reading this forum, I was able to figure it out.

 

No flooding here. I have a question regarding drive train noise. I have a 2004 RX8 4 speed auto. When after shifting into drive or reverse and just as I roll of I hear a noise coming from the differential or drive train. It sounds like something engageing, say maybe the limited slip diff??? The shop mech says he does not hear it.?????

 

About the flooding, I was told that when moving the car (RX8) a short distance on cold or hot soaked engine to rev the engine to 4000 rpm and turn of key. This blows excess fuel out the back and helps prevent flooding next startup.

 

I have a problem every time I wash my car. I pull out of the garage, turn it off, wash it, start it up and pull it back in the garage. When I go to start it up again (anywhere from a few hours or a day later), it will not start. Fluding, I think! This has happened twice.

 

What you need to do is if you ever just move the car quick and shut it off, next time you start it push the gas pedal all the way down to the floor while you crank it. Just let it spin over for a second or two and then take your foot off the gas while still cranking. It should start. This is in the manual as the unflood procedure but if you do it my way it is more of a flood prevention procedure. If it floods, it is too late. It is not a guarantee that it will not flood but it will greatly reduce the odds.

 

I need to change my vote in this poll- I went from
"No" to "Yes" today.

Oh - and my service manager claims he had about 100 8's towed in this winter for the flooding problems- Bit of tall tale wouldn't you say?

The 8 looks pretty good even on the back of a flat bed! I should have taken a picture.

 

My RX8 flooded yesterday and was the first time. I had to tow it to the dealership where they change the plugs and reset the system. They told me that they got a bulleting with instructions how to reset the computer to change the amount of gas to be used on a start. I wander why we dont get any messages from Mazda either to come to them to reset the computer or to explain what can happen to avoid the problem. In my case the day before I start up only for a few seconds to take it our from the garage for a was and then move it back.

 

It flooded for the 2nd time this AM. It better be covered in full. I am so tired of this crap! I don't have time for this. The 8 is proving to be very unreliable!

Is flooding covered under our warranty?

 

All of you people who keep saying that your cars have flooded. I GUARANTEE that I could drive your cars and not flood it once, ever! No I would not need to wait for it to warm up. I've already said how elsewhere on this forum. It is very easy and you don't have to change anything on the car. You don't have to rev it up before you turn it off and you don't need a turbo timer. Learn how to treat your cars. If I can get it not to flood, it must not be a defect. I've owned several rotaries long enough to know how to not flood them.

 

Isn't it possible that due to very slight differences some RX-8s are more prone to flooding than others? In the same way that people have been reporting very different gas mileage even for similar driving?

 

We're all going to laugh hysterically when you flood rotarygod (jk)

 

Yes. See this thread. Any incidence of RX-8 flooding, whether it be dealer service or towing, is covered uner Mazda New Vehicle Warranty (48months/50,000 miles).

 

Maybe. That is irrelevant. There is a way to start the car everytime. I am the only person who can start my '84 RX-7 aside from the person who taught me how. Everyone else will flood it. Even before I learned how to start it, when I did flood it I didn't need a tow truck. I wouldn't need a tow truck for a flooded automatic. People need to learn what their car needs and how to get out of a potentially bad situation. the unflood procedure in the manual is actually a very good idea. Just don't wait until it floods to do it. It is too late. Be proactive rather than retroactive.

One person's idea of similar driving by pure description through words is purely subjective.