Tip\'s to stop flooding

Carl · December 18, 2008, 08:22:48 AM

Rotaries with fuel injection can be easy to flood the engine with fuel,then it wont start and has to be deflooded.
Here are two things that will help,but also remember to keep your engine properly serviced.

Tips for not getting into this situation for this who are worried.

1. Try to make sure engine is warm before shutting down.( Moving the car short hops,such as your drive from garage then shutting down is not good)
2. When shutting down,hold accelerator pedal down to keep the revs up at around 3000 to 4000 rpm,then at the exact same moment you turn off the ignition put your foot fully down on the accelerator pedal,and hold it down till the engine stops turning.(Dont forget turbo timers!)

What does that do you might ask?

Well when the ignition is shut off both fuel and spark stop,but if you are at the higher rpm and then put your foot to floor it makes sure that the engine internals are dry from fuel with plenty of air going into the engine.

You should never flood it again if you get into the habit of following these two simple steps all the time.

Regards
Carl

hairyhoover · December 18, 2008, 08:48:53 AM

I always tend to turn the engine off at 3000rpm as well, it should make the water seals last longer as well.

clive · December 18, 2008, 09:07:17 AM

Thanks Carl this is an excellent tip for our members

Mazda actually recommend turning off the engine at around 4,000 revs on the RX-8 once warm, as you say fuel and ignition cut off simultaneously and then the spinning Rotors pump out any excess fuel as the engine comes to a stop :Viking

Rzla · December 18, 2008, 09:33:05 AM

Quote from: hairyhoover;566629I always tend to turn the engine off at 3000rpm as well, it should make the water seals last longer as well.

can you please explain the water seals part...

Carl · December 18, 2008, 09:56:21 AM

Quote from: Rzla;566634can you please explain the water seals part...

If you flood engine then residual fuel stays in bottom of engine,which leaks slowly into water seals and damages them over time,so it is best to deflood quickly and not leave engine for long periods of time in a flooded state.
Regards
Carl

Prof · December 18, 2008, 10:02:27 AM

I heard it also gets into the oil system - diluting the oil - is that also true ?

Bobbit · December 18, 2008, 10:27:58 AM

Quote from: Carl;566641If you flood engine then residual fuel stays in bottom of engine,which leaks slowly into water seals and damages them over time,so it is best to deflood quickly and not leave engine for long periods of time in a flooded state.
Regards
Carl

Hi Clive,
How long does it take for the seals to fail if the engine has been flooded. Only reason i\'m asking is that my Fd is at a garage getting the rear bumper repaired and they cannot get it started, sounds like they\'ve flooded it and it been almost a week now.

clive · December 18, 2008, 11:45:51 AM

As Carl says this would be over a period of time and the fuel would then attack the water seals, i.e. if an engine was flooded and left for months and months,

Nik da Greek · December 18, 2008, 11:53:57 AM

That shut-down-at-4k tip is a piece of genius! My neighbours will be especially pleased with my new-found mechanical sensitivity when I get home from work today at two in the morning! :Giggle

Bobbit · December 18, 2008, 12:36:26 PM

Ok, so it shouild be fine then. Thanks

L18M · December 18, 2008, 01:02:03 PM

i heard some people say that shutting down at 3-4k rpm can damage the turbo (due to no oil lubricating the turbo) in turbo cars?

nikp · December 18, 2008, 01:38:19 PM

Quote from: Carl;566641If you flood engine then residual fuel stays in bottom of engine,which leaks slowly into water seals and damages them over time,so it is best to deflood quickly and not leave engine for long periods of time in a flooded state.
Regards
Carl

I can go along with that. A few years ago mine was left about 2 weeks flooded. Later that year (still several months though) the water seals failed. I don\'t think it was a coincidence.

probedb · December 18, 2008, 01:41:12 PM

Quote from: BBCFC;566721i heard some people say that shutting down at 3-4k rpm can damage the turbo (due to no oil lubricating the turbo) in turbo cars?

So do you believe \'some people\' or Carl, a rotary specialist of many years?

DRAGON · December 18, 2008, 01:45:48 PM

Quote from: probedb;566734So do you believe \'some people\' or Carl, a rotary specialist of many years?

Good Question!

L18M · December 18, 2008, 02:12:45 PM

Quote from: probedb;566734So do you believe \'some people\' or Carl, a rotary specialist of many years?

it was only a question.. plus carls post does not say anything about if it is good or bad for the turbo, just that it will help prevent flooding.

actually come think of it.. i think carl said that himself when i was up there yearlier in the year.
he told me about this 3.5k shut off n followed on saying that it might not be good for the turbo as theres no oil getting to the turbo for lubrication and can mess up the bearings in the turbo.
also heard this from another mechanic.

Ps im not doubting carl. i know he knows a lot about rx\'s