Whats this? "Pic"
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Joined: Oct 2001
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From: Miami Beach
Whats this? "Pic"
It looks like the hose is just in there to let in air when tha tank is creating vacum. Is this correct?
I remember there being a writeup on removing the Check and cut valve and charcoal canister. Does anyone remember this?
I remember there being a writeup on removing the Check and cut valve and charcoal canister. Does anyone remember this?
The cut and check valve and the hose that goes into the little cup mounted on the frame rail is a safety item. During a rollover accident the cut and check shuts off the fuel so the tank doesn't drain out when the car is upside down, thereby preventing a fire. The little cup contains what fuel runs out before the flow is shut off. It also keeps contaminates out of the fuel tank.
FD > FB > FC
Joined: Oct 2002
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From: Bothell, WA
yeah that makes alot of sence, I rolled my last rx7, and it ended up side down, and during the roll over my fuel send line to my fuel pressure regulator broke off, and I had the ignition on for a good 5 minutes but there wasnt fuel everywhere
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Thread Starter
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From: Miami Beach
dj55b............... http://www.wankel.net/~krwright/cars/rx7/manuals.html
www.iluvmyrx7.com
OK so I decide to keep the canister, but I will relocate it to the rear of the car. My other question is will I have to route a line from the canister to the oil neck like this, or can I vent the line to atmosphere?
www.iluvmyrx7.com
OK so I decide to keep the canister, but I will relocate it to the rear of the car. My other question is will I have to route a line from the canister to the oil neck like this, or can I vent the line to atmosphere?
Thread Starter
Joined: Oct 2001
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From: Miami Beach
Houston We have a problem
Well I got under the car to plug in all the hoses and something did'nt seem right. The Check and Cut Valve was missing something. It looks like who ever had the car before me (more than 8 years ago), broke a nipple on the valve and bypassed it.
I think this is the way it goes.
I'm taking out the check valve from my parts car, and I'm ordering a new fuel pump. http://www.msdignition.com/fuel_7.htm $123.49
Hope to continue next week.
Well I got under the car to plug in all the hoses and something did'nt seem right. The Check and Cut Valve was missing something. It looks like who ever had the car before me (more than 8 years ago), broke a nipple on the valve and bypassed it.
I think this is the way it goes.
I'm taking out the check valve from my parts car, and I'm ordering a new fuel pump. http://www.msdignition.com/fuel_7.htm $123.49
Hope to continue next week.
the one by the fuel pump stops fuel from flowing if the car is upside down, ditched that on my project car, the other one has something to do with the vapor return, it was rusted so i ditched that too. They both seem pretty useless
no, i just bypassed that valve, so it goes from the metal hardline right to the tank instead of through that valve. Granted I haven't actually run the car yet, but it *should* be fine 
Thread Starter
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From: Miami Beach
I've read that the check and cut valve also keeps equal pressure in tank. It opens when the air inside the tank reaches 1psi. I think it also opens to let air in when the tank creates vacum.
Anyone feel free to jump in anytime now
Anyone feel free to jump in anytime now
Thread Starter
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From: Miami Beach
Here you go.
There is a pressure relief valve at the tank. It's called the check-and-cut valve and it mounted under the car near the tank. It's inline with the line that vents the fuel tank vapours into the charcoal canistor. Its purpose is to ensure the tank does not experience either positive or negative pressure. It's a 3-way valve, and if the tank pressure is ~1psi above or below atmospheric it will vent through the third leg which is open to atmoshpere.
If your tank is pressurising, this valve is probably faulty and should be replaced. This should fix your problems.
As for charcoal canister removal, I'd leave the lines open, but I'd disconnect the line at the check-and-cut valve. This way any venting to atmosphere is done at the tank, not in the engine bay. Leave the check-and-cut valve in place and working, so the tank's only venting when needed
If your tank is pressurising, this valve is probably faulty and should be replaced. This should fix your problems.
As for charcoal canister removal, I'd leave the lines open, but I'd disconnect the line at the check-and-cut valve. This way any venting to atmosphere is done at the tank, not in the engine bay. Leave the check-and-cut valve in place and working, so the tank's only venting when needed
Thread Starter
Joined: Oct 2001
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From: Miami Beach
Well I put a new check cut Valve back on, but decided to ditch the canister and route the vent line to the rear under the bumper.
Now I just have to decide what fuel pump to buy.
Now I just have to decide what fuel pump to buy.
Nikki-Modder Rex-Rodder
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From: Trying to convince some clown not to put a Holley 600 on his 12a.
Two of my friends have wound up in cars upsidedown and soaked in fuel.
One girl had a compound leg fracture and was pinned. She was soaked in gas and couldn't get free. Our local firemen nearly drown her in foam.
The other friend died, but he was also saturated in gas.
Removing that checkvalve alltogether will not increase performance. IMO, removing it is a stupid thing to do.
One girl had a compound leg fracture and was pinned. She was soaked in gas and couldn't get free. Our local firemen nearly drown her in foam.
The other friend died, but he was also saturated in gas.
Removing that checkvalve alltogether will not increase performance. IMO, removing it is a stupid thing to do.