brettbrecklin

Hello guys, my name is Brett and I'm new to the rotary scene. My friend is selling me a worked '85 GSL with the rat's nest removed, Pacesetter exhaust, etc etc. Right now it runs rich enough to collect raw fuel in the exhaust tips. I cannot imagine this would be very easy on the apex seals in the engine. He says that the only real way to fix this is replace the "air vane?" This is a fuel injected car unfortunately so it seems as if the problems will continue to arise. I searched through the forums on various topics but didnt come up with any suitable results. The car gets horrible gas mileage but otherwise seems to run alright. Any ideas or suggestions? Thanks a lot guys!

gsl-se addict

iTrader: (3)

Welcome, Brett. It sounds like your car is a GSL-SE if it is fuel injected. Your engine should have a box on top that says RE-EGI on it. If it is a GSL-SE, your friend must be talking about the air flow meter (AFM). The kind of AFM used on these cars is called a vane type. Let us know if your car is a GSL-SE (with the 13b fuel injected motor) or the carbed motor found in the GSL. That will help us determine your problem.

Kent

brettbrecklin

Thank you for your reply, Kent. It is in fact the GSL-SE, sorry I failed to make note of that. It is fuel injected with the 13b engine. It has factory disc brakes, front and rear, and also a limited slip rear end (or so I was told.)

This AFM, can I find a diagram online somewhere explaining to me how it functions? I know next to nothing when it comes to fuel injection and nothing at all about rotaries. Could there be an easy fix to this pig rich problem, or is it an extensive project? If I do get the car and this repair turn out to be a nightmare, I would scrap the fuel injection and run a carb setup. The simple "air bleed screw" seems much easier to tune. Could I just install a fuel pressure regulator in line with the fuel line to cut down fuel flow? From what I understand, our engines operate much like a two stroke engine. If the fuel flow is not precise, could damage occur?

Sorry for the questions, it probably sounds like a broken record. I really do appreciate any advice you guys can give me. Once again thanks Kent for the information!
-Brett

hammmy

http://www.wankel.net/%7Ekrwright/ca...85_manual.html

That's the '85 manual. The 13B sections are devoted to the -SE's motor.

Don't be afraid of the fuel injection.

-dave

BlastinSideways12A

Stick with the EFI. Just take your time and learn the function of every component of the system. And by all means ask questions. Thats how I have learned much of what I know. You could always get a Megasquirt and get rid of the stock ECU and the air flow meter thats thought to be causing your problem. You'll pick up some power too, especially with other mods.

I'm currently working on a 12A gas mileage project which is going to use some EFI hardware from a GSL-SE (center housing, upper manifold, plenum, and throttle body), a lower manifold for a side-draft carb intake, TII injectors, and a Megasquirt to control it all. Hoping for 30 MPG on the highway and low 20s around town once I get the ignition tuned. In the spring I will probably be fine tuning everything on an engine dyno that my university had bought 5 years ago and never has set up. There are a group of 3 senior Mechanical Engineers working on it plus myself (junior Mechanical Engineer with some electronics experience) who has just joined in to help them out. They are good with designing the mounts for it but really don't know where to begin as far as setting everything up for data aquisition. Hopefully we can all use our strengths to get it up and running then I can play with the 12A and the S5 13B that I'm working on.

The rotary is actually a 4 cycle engine, it goes through intake, compression, combustion, exhaust. The thing that makes people think that its a 2 cycle engine is the fact that it injects oil into the combustion chamber for lubrication of the apex, side, and corner seals.

Good luck with it.

LokiRx7.1

iTrader: (1)

Apex seals shouldnt be affected much by running rich, hell I run so rich at times i have fuel dripping from my exhaust..... and I have a carburated 12A.... its all in how you tune it. My gas mileage is also horrifying. With factory injectors you should be able to get decent mileage. Definately replace the AFM I see no reason why that wouldnt solve any issues you may have.

brettbrecklin

Thanks again for the helpful tips guys! I think some computer modifying would be helpful in the long run, but right away I plan on replacing the AFM. Anything else I need to know?

Loki, this one runs rich enough that we actually lit the exhaust coming from the tip on fire with a large butane lighter.

frisbeedog

Before you replace the AFM, make sure that the little flapper door opens easily. Pull out the filter and look at the little bronze door. It should open easily. Good luck.

SCCAIT7

If you need an AFM...Let me know... I have a couple ill sell cheap..like $25 plus shipping....PM or email me at Hproduction38@aol.com.

brettbrecklin

FrisbeeDog, he has rebuilt this one before not too long ago so I dont really think a problem lies on the flapper. Thanks for the suggestion as this is basically what the cause of the illness is, I think. SCCAIT7, that is a kind offer. I will get back to you once I have the car in my possession and begin tinkering. Thanks a lot guys!

TopGunM2k

Hey Loki, so is there such a thing as running too rich?
I currently have a street ported 13b 4 port with a weber 48 ida....and let's just say my driveway smells like a gas sation when I start up the car.

LongDuck

As the prior posters have pointed out, there are a number of sensors and senders that need to be looked at when an SE is running rich in a constant mode. While changing out the AFM is a good first step (if you have one around), I would caution you to keep the old one on-hand in case you find that the new AFM doesn't fix the problem.

Some other things to replace/check using the FSM instructions:

1) O2 sensor - the SE uses one in the exhaust manifold and if your 'Pacesetter' headers (crap, btw) don't have a bung for the O2 sensor, then your computer is not able to run in closed-loop EFI mapping, resulting in overly rich mixtures at steady state throttle and cruise conditions

2) Intake air temperature sensors (2) - one in the AFM which gets replaced when you change the AFM, and another on the RE-EGI chamber underneath the BACV valving solenoid (driver's side, just above the bottom edge of the dynamic chamber). These tell the ECU what temperature the intake air charge is and subsequently how much fuel will need to be injected via pulse width to get a stoichiometric balance (14.7:1 ideal air/fuel ratio). If a sensor is out or unplugged, then the computer will think the intake air is cold and will run a rich mixture to compensate.

3) Coolant temp sensor (back of waterpump, near the inlet) - serving a similar function as #2, this sensor tells the computer when to run rich to assist with cold start conditions.

4) Therowax Pellet at back of Throttle Body - this is a heat-based vacuum switch which uses coolant pumped from the back of the waterpump to determine when the engine is warmed up, shutting off vacuum to the 'double throttles' which serve as chokes in the SE to give a rich mixture under cold start conditions.

5) Leaky injector(s) - obviously, if you have a stuck injector, it's running wide open and not in pulse width mode.

Have a look at these things and report back and we can go from there, HTH,

brettbrecklin

LongDuck, your plethora of information is surely appreciated. I will do a check on these items and report back. Thanks a lot dude, once again it is appreciated!

By the way, the RX in your signature is really sweet.