Before i even get into the problem and my thoughts on a solution, this is my car:

1984 RX7 GSL
Rats nest removed
Racing beat header to a no cat custom stainless exhaust
Mazdaspeed air intake kit
MSD 6A Direct fire ignition with MSD blater coils

Oh and FWIW car has been running perfect up until late last fall when it started this flooding issue and the flooding issue was well after the rats nest removal.

Okay, so i have searched and tried to troubleshoot my carb myself. Basically its like this:

Car starts perfect and runs like a raped ape.

If it sits for anything longer than 10 minutes after i turn off the engine, it floods really bad when i try to start it. When i say really bad i mean fuel pouring into the carb, wont stop and one time flooded over the top of the carb itself! :o

If i wait like 2 hours or so it starts right up again

So i have been searching on here and from what i can gather it might be my float bowl vent solenoid. So i looked and its hooked up as it should be... At least i think it is, i took a pic of it after i pulled it off the car to make sure the lines to it and from it were not clogged, here is the pic:



We are talking about the same part right?

Now, here is my thought on solutions (please tell me if i am nut, need a new carb or all of the above).

1. Get some carb cleaner and spray the heck out of it (will this really help? My thought is that maybe something is stuck wide open and wont shut)

2. Replace the float bowl solenoid in hopes that is the problem.

Does the float bowl solenoid ever go bad? It doesnt look like a very complex part... Really i am hoping its something simple.

Rotary gods, please help! I know worse case scenario is a carb rebuild or a new carb, but i would really hope it was something simple.

Sorry for the long post!

 

No that is just a check valve. Possibility that the needle/seat is stuck from varnish. That is what controls the flow of fuel into the float bowls until the floats rise and close the needle seat. Try tapping on the tops of the carb where the fuel lines go in. Sometimes this will cure the problem. For detailed info on the carb go the FSM link as provided by trochoids profile.

 

Where the heck is the float bowl solenoid then?

 

traditionally flooding carb = sunk floats....

that delay valve is for the choke system, if it runs crappy with the choke on, that valve can be the cause. although at this age/mileage the pull off diaphrams are bad too.

 

https://www.rx7club.com/members/trochoid-48364/

 

Yeah, thanks, but no offense, but i dont really think that is the greatest and easiest place to send someone like me. I downloaded the carb manuals a week ago studied them and still had no luck.

BTW, i found the air vent solenoid and it is hooked up, could it have gone bad?

And so tapping on the top of the carb is my next possible solution? Thats not in the carb manual

 

The vent solenoid is actually attached to the carb, on the drivers side up near the top. It has one wire comming out of it. This wire should have battery power to it when the key is in the on position I believe. If this wire isn't hooked up, it would cause the symptoms you are talking about. I had the exact same problem with my Nikki back when i was still running that carb and it turned out I had forgot to plug that solenoid in. Its possible that the wire is broken somewhere causing it to not work correctly.

Contrary to what others have said, its not your floats sticking. If that was the case then the carb would flood while the car is running, not while its off. Chances are its something to do with your vent solenoid.

 

Okay, so i started up the car, let it warm up, tapped on the top of the carb as suggested by RX7Doctor and then took it for a spin, ran excellent.

Came home, turned it off and went inside and made the best turkey sandwich i have ever had in my entire life, yum.

Approximately 25 minutes went by.

Went back outside to check and see if the tapping had solved the problem.

As i entered the garage i could smell gasoline... a lot of gasoline, so i opened up the garage door then i opened the hood to the rx7.

It sounded like a coffee pot or maybe darth vader gargling listerine.

Took off the air filter and this is what i saw:





Any ideas? I can assume that it was much worse than this as gas had spilled all over the block and onto the garage floor!

WTF?

 

You have 12 volts going to your vent solenoid? Is your fuel pump running when you turn off the ignition? Is your return line for the carb hooked up? Some things to check.

 

Either your floats are soaked in fuel (meaning they have a hole in them), or the floats are stuck in the down position not closing the needle to the set, or you have a dirty seat. Either way, you need a rebuild. Don't be alarmed. It's not that big a deal. You can do it your self. Most parts houses can get the rebuild kits for less than 50 bucks. You will need a can of solvent to soak the carb and parts in. These usually run 10 to 15 bucks. If you take your time, and study the carb manual, you will do ok.

 

Now i am getting two different opinions, is it definetly in need of a rebuild or could this happen if the air vent has no power going to it like 85rotary power said?

Again, this only happens when the car is turned off.

 

Alright, has anyone ever seen a bad or improperly hooked up air vent solenoid cause this much flooding?

 

I know you said it was running well after the rats nest was removed, but I had a similar problem.
I removed the rats nest from my 79 following the tutorial, started up fine idled fine, I shut the car off sounds like a percolator (gurgle gurgle) fuel is filling up the carb after I turn off the ignition.
Car won’t start I retrace everything to the Coasting Valve, hook up just the Coasting Valve alone flooding stops.
I put the rats nest back on life is good.
I am just saying in my case it was the Coasting Valve’s removal that caused the flooding.

 

Is your fuel pump shutting off when you turn off the car? Listen for it in the rear of the car. Even if both needle valves were held open by obstructions there wouldn't be any pressure left in the lines for it to continue spewwing gas after half an hour.

 

Agreed. But it doesnt sound like my fuel pump is still on? How loud is it going to be?

 

I agree, that's alot of freaking gas to have just come out of the bowls...it looks like the pump is still running??? Take the supply line off see if it's still flowing, hook it back up and take the return line offf and see if fuel is circulating...unhook that single wire(solenoid), then turn your key on, then hook it back up...you should hear a click sound when you make contact w/the wires, if not it's bad.
Still could be a float, a needle or needle seat. I had overflow similiar(once because I put a gasket on upside down) but once because the top-plate gasket wasn't sealing right. I dunno but I've had a belly full of my nikki, seems I finally got it right...but those things I mentioned I would check first.

 

Plus wouldnt it just keep running and running? Does anyone know what fuse it is off the top of there head that controls the fuel pump? Couldnt i just pull the fuse and see if thats the problem?

 

What in the hell do you have in your fuel system? That doesn't look like raw fuel, it looks congealed like something else is mixed in with it. Something is definitely wrong there.

 

*edit* sorry

 

you should be able to hear fuel pump running if you stick your ear under the car right in front of the drivers rear tire.
and if it's running after you turn the key off I don't believe pulling any fuse is gonna help you because it's either hooked to the constant side of the fuse block or hooked up direct...just eliminate that first then move on to something else.

 

The fuel is as clean and clear as gas gets (new filter put on last fall).

What you saw was the fuel bubling and moving around like it was boiling!

 

I will try that Wednesday, i will be in Chicago all day tomorrow. Thanks, i will let everyone know.

 

that looks mad weird.....there is something very fishy, if i saw that in my rx id be scared, keep a fire extinguisher around just incase

 

Word, it scares the crap out of me. I am going to tear into the problem tomorrow

 

Fuel shouldn't be boiling in the carb like that. Something is too hot and causing the boiling. When fuel boils like that, it will often cause vaporlock.