Fo whatever reason I don't know, My '88 on turbo , I have to unflood every time now. It has gotten consistntly worse. What could be the major causes, and what are my possible solutions? I would bring it to a mechanic down here, but nobody really knows how to mes with a wankel engine.. Thanks for running a great site! I am located in South Louisiana, any neighbors?

 

You can have a leaking injector, or low compression. Though it can be many things but usually, if the engine floods after lets say, from parking overnight, then the injectors might be leaking gas into the chambers.

 

Try to diagnose it yourself. I've found most mechanics don't know anything about rotaries even though they'll say they do. +1 on the leaky injectors, but it could be many things like black knight was saying.

 

could a bad oxygen sensor be a real problem for anything?

 

how many different ways arthere to treat low compression.

 

I don't think an O2 sensor would cause it to flood that bad, +1 on the leaky injectors I would definitely look into that, pull them and have them inspected somewhere, although you may have to send them in somewhere since you might not have any shops in your area.

 

rebuild lol

Get a compression gauge, take out the shrader (sp?) and take out the lower plugs and attach the gauge and crank. You should see bounces higher then 70-80 if not then your engine probably needs a rebuild. Search the forum for compression test methods.

 

Some possibilities:
1. Fuel injectors need cleaning. This is a 30k mile normal maintenance item--if it has not been done in that time or you have not owned the car that long then it becomes more likely.
2. O2 sensor is probably *not* it, though if it has more than 30k miles on it you should probably change it out as well.
3. Low compression

Nobody seems to really know what the logic is inside the ECU, but here are some other things to check (use FSM procedures) that it *might* be using to determine mixture at start up:
4. Boost sensor
5. Air pressure sensor
6. Air flow sensor

A lot of people have installed 'hot start' buttons in their S4 RX7's; all it is is a momentary contact switch that kills power to either the fuel pump or the injectors. If you have a flooded start, you crank it with the switch depressed and the throttle full and it clears the flood. After that it will start normally.

I wired mine so that it is active only when the starter is energized. Of course, since I put it in, mine has never once flooded since...

 

My Uncle, a great deisel and gas diagnostistic (no wankel though), Has found that I have an exaust leak coming through the radiator. Could this just be apex seals that are bad , or is there something cracked. We pulled the overflow line off and stuck it into a gallon of water, reved it up and as it reved down, bubbles were floating up. Also, when I do start it, as soon as it starts, the hose from the radiator towards the water pump looks like a balloon. I know that I am not leaving that much air in the coolant, or am I. Thanks for replies.

how would i find the information on how to do this correctly? No jigga rigging! And why would we really need to do this if our engines ran properly?

what's the shrader (sp?)

 

This is not a sign of an apex seal, but a coolant seal failure. A rebuild is required, but the good news is that there is that the likelihood of major parts being damaged is relatively low.

Just don't hate the car and store it, the water will leak and rust everything to eachother.

 

I vote for the post above as to what your problem is, now that you mention exhaust gas in the coolant.

Attached are jpg from PINEAPPLE RACING and are jpgs of an engine being taken apart. See your local FSM for the how to rebuild an engine.

 

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And finally the last jpg attached.

Our ECU's are old technology. Unlike modern PCM or ECU that have things like fuel monitors, oxygen monitors etc, ours do NOT have that latest greatest technology. Modern ECU's fuel monitors.....well they monitor the fuel content in the exhaust gas anytime the engine is running and have features like STFT (short term fuel trim) and LTFT (long term fuel trim) and these monitors help prevent an overly rich or lean conditon while driving, UNLIKE your old RX-7 ECU which does NOT trim fuel at all in the manner of the modern PCM/ECU.

Except in a very limited way such as using the 02 sensor when cruising to try to maintain a stoic fuel mixture under light load conditons. 02 sensor is not used for starting in any manner and is only used over 1500 while driving in a steady manner.

Your engine is TOAST. Rebuild it like the man above said.

 

when rebuilding, are there any other things I should update or improve? I am keeping it as a daily driver. And thanks for the pics. I'm sure it'll be interesting to crack that shell open and pop my wankel cherry!

 

I would consider getting a streetport on your motor. Might cost $200 more at most shops.

Otherwise, if you really want to modify your turbo car, the options start with the fuel injectors, getting something to control the bigger injectors (computer apexi safc / megasquirt), and a bigger turbo. NOTE: Expensive Route To Go as a shop should probably do a lot of tuning.

 

sorry I guess I left out that it's not a turbo. Also I don't understand yet what the different types of ports are, or how I could change 'em

 

http://www.fc3spro.com/TECH/PORT/porting.html

if you are going to rebuild, let a rotaryengine shop rebuild it if you are not sure of how to. Last thing you want is to finish rebuilding it and then found out it wont start because you did something wrong.

The shrader valve is the needle in the compression tester. It lets air in but not out.

 

dont push your gas pedal down when you start your car it floods it almost everytime. prime the fuel injectors by clicking the key on and off into the on position without cranking. let the fuel pump build its pressure then try starting it. rotarys are bad when it comes to regulating the amount of gas it puts into the housing so therefore they flood easy. i drive an N/a in the proccess of turboing it myself and my car never floods but i have 3 friends who all drive turbo2's and they have the same problem. its just one that comes with a tuboed rotary engine i guess hope this helps

 

Just one.