tunafish

First excuse my lack of knowledge regarding the engine I would say I tip toe around this engine very cautiously. Here is the problem vacuum lines rotting do to age decide if I have to replace why not take out rat’s nest. So I did, car starts back out of garage, sounds pretty good too, I notice lots of white gray smoke out tail pipe, I shut it off and hear this gurgling sound I have no idea what it is. Car starts up again same thing (choke out) shut it off (key out of ignition) more gurgling take off air cleaner (I know very little about carbs) the butterfly is closed on the primaries and gas is pouring in on top of the butterfly (which is closed) the car no longer will start I try starting several times and the same thing happens gas rushes in after key is turned off The obvious is put the rats nest back on but I like the clean look Does anyone you have any idea what is causing this, I could really use some help.

Thanks to all in advance

excitingleopard

You know more about enjines than me.

Rx7carl

Sounds like you may have stuck floats. Did you disconnect the vent solenoid? It needs to be working. Also did you use our tutorial on the rats nest? or did you do it yourself?

Cody

tunafish

The vent soleniod is working correctly except with ignition off when I blow through vent hose gas runs into carb on top of closed butterfly? I think only air should blow through, With ignition on can't blow through carb vent hose.

Rx7carl

Well when you blow and flood the engine, the bowls are already overfull it sounds like. I think you have sticky floats/needle valves.

tunafish

Carl I sent you an e-mail very lenthy hope I had the right adress why would float neddle valve be working before the removal of the rats nest yesterdat I took off the site glass and moved the float up and down with my finger. Is it normal when blowing into the carb vent for gas to come out?

The_7

hey carl, what does the vent solenoid do? i took off my rats nest a week ago and just kept the purge valve and the vacuum advance lines and my car runs (not good but it starts and runs).

Rx7carl

Tuna, I didnt get it. Try DC871@aol.com
Where did you blow into? The stub tube next to the solenoid? And where did the gas come out of?

7, it prevents polluting fuel fume vapors from getting into the atmosphere when the car is off. The sol shuts the vent when the car is off, trapping the vapors in the carb, and instead vents it to the cannister.

tunafish

Carl, I pulled off the vacuum line and put a short one in its place and blew through it, yes it is next to the solenoid. Gas comes out of these little metal tubes on top of carb, hard to explain four holes or ventures with inner rings these short tubes are pointed toward these inner rings I think they are called Primary and secondary main air bleeds. Gas runs into both when you blow or shut the car off , I go around the passenger side and blow though the tube and actually watch the gas run in, as long as I blow gas runs in then I siphon it out with a gas siphon you know the ones they use to sell to steal gas out of cars (Ive had it a long time).

tunafish

Forgot to add this is 1979 limited edition never had a charcoal canister for venting. At least mine did not. Ohio emissions

Rx7carl

Ahhhhhhh. Those are the fuel nozzles. Thats where the fuel goes into the carb. The "inner rings" are the booster venturis. The short tubes are brass colored right? When you blow into the vent your pressurizing the bowls, fuel WILL come out of the nozzles if the vent is open.

79's had a charcoal filter in the air cleaner top, right in the middle of the cover instead of the cannister of the later models.

tunafish

Yes, Carl the short tubes are brass colored. Of course you are correct the charcoal canister is in the air cleaner I have a BAE turbocharger kit and use an Edelbrock triangular shaped air cleaner (foam insert). You say fuel WILL come out if the vent is open but should the vent be open when car is shut off? The manual reads like it should but that doesn’t seem right. I hope you got my e-mail I resent.

Rx7r4c3r

I have the exact same problem !!! When I dont have the pcv system hooked up everything is fine. I hook up the top hose of the purge valve to the 4th opening on the carb. Then I hook up the bottom smaller hose on the purge valve to the 3rd opening from the left. Then run a hose from the oil fill pipe vent to a 5/16 3 way splitter. Then from the splitter run a hose to purge valve. Then run a hose from the splitter to your carb vent. This is the big 5/16 hole on the carb near the vent solenoid. I run the car fine with everything blocked off, But as we all know pcv is very important. When I hook up the pcv system everything is fine till I turn my car off. When I turn my car of it sounds like sizzling from in my carb. Upon inspection inside the secondary barrels on my carb, I see alot of gas bubling inside the secondarys ontop of the closed buterfly's. Weird...

Anyways I took the pcv system of and everything is fine. I followed the instructions from rx7carls tutorial. If anyone can tell me the correct way to connect the purge valve I would be very gratefull. Im 100% you got the same problem as me I hope someone can help us.

Btw: I also have a 80' model with no charcoal canister. my charcoal canister is inside my air cleaner. I run a hose from my gastank vent hose on the firewall to the smaller hole near the oil fill pipe. This may be my problem?? I have 81-83 engine in the car Thanks in advance.

Rx7r4c3r

I found out what the problem is, I ran my fueltank vent line located on the firewall to my intermediate housing. With this hooked up my secondary's fill with fuel when I turn the car off. I d/c it and problem solved. I have a 1980 rx7 and my charcoal canister is in my aircleaner. Hope this helps...

tunafish

Rx7r4c3r, I was going to wait until I had completed all the work on my vacuum lines to give an update. I had run the gas tank vent hose to the bottom of the purge valve I believe this where it is shown in the tutorial Im pretty sure I did the tutorial correctly when I e-mailed Carl he said I didnt know you had a turbo. That is probably why the rats nest removal did not work for me that carb spacer where the vacuum lines connect had to modified. According to the turbo install vacuum lines were also rerouted and the anti-afterburn valve removed along with other stuff. Anyway I hook up the coasting valve since this was not in the tutorial I think that was an automatic not sure but the 79 manual transmission Has a coasting valve the gas flooding in after I shut off the car stopped so I figure hell if I gotta have that I will put the rats nest back on. I did car runs very smooth but stalls more then ever, off the high idle warm up every time you stop so I am replacing all vacuum line I have a VDO boost gauge tapped into the intake manifold. I read about the brake booster vacuum lines I am even going to take off the blocking plates and use new gasket sealant its been 20 years since they were sealed I will also do a complete tune up points plugs new dist. Cap and rotor I still think I have a vacuum leak somewhere.
Carl and Sterling thanks again for your help.

MIKE-P-28

iTrader: (1)

I bet you capped of the air vent solenoid... tisk tisk , thats probally the problem

you need to leave that line open

tunafish

I hooked up the purge valve as instructed according to the tutorial. From the oil fill pipe run a hose, from the carb vent run a hose to a T fitting, connect to bottom of purge valve and connect all three. I never capped the carb vent at any time. With the coasting valve off gas pours down on the butterfly with it hooked up there is no problem and that’s without the rest of the rats nest put back on, only using the coasting valve.

Rx7carl

Well with the turbo setup that changes the whole thing I would think. With a pressurized intake I dont think youd want to connect the vent to the crankcase cause itll pressureize it. Maybe ask about this in the turbo section, or try the guys at www.turbofb.com I bet they'll have a good answer for you.

Hmmmm another thought. Venting the carb to a low pressure source (the crankcaes vent) may be causing the flooding. Im not too familiar with turbo setups and how they affect this sorry.