The_7

i was drawing out a map of my fuel system when i discovered 2 parts under the car in the rear that i dont know what they are. check out the picture and see if u know that they are. TIA

magnanimus

The valve to from your charcoal canister is your fuel check and cut valve, I removed mine and replaced it with a tee. The other item from the intake, which I believe is between your Pump and Tank, is the fuel cut valve. This valve cuts the gas if your car truns over, at least thats what a Mazda mechanic said. I also removed it. The item you are missing is the fuel check valve from the return line it is located in the engine compartment on the return line. I think its good to keep that.

Jeff20B

iTrader: (13)

I turned all three into sending lines on mine. Easier than running a new, bigger line.

Rx7carl

magnanimus hit it on the head. But the rollover valve is actually b4 the filter The7. At least best as I can recall.

85rotarypower

Yep, the cut valve is before the filter. Your line from the tank should go to the cut valve, then to filter, then to pump then to the carb.

The_7

i could have mapped it wrong, i will check it tommorow to make sure.

what is the purpose of the check and cut valve in the evap line?

Jeff20B

iTrader: (13)

I removed that checkball thing from my evap line. I still have the roll-over one though.

The_7

so its not that important then? cause ill just rip it out to if i dont need it. what does it do?

also i checked under the car again and the cut valve is defenatly after the pump on mine, u guys are sure its supposed to be before the filter?

Jeff20B

iTrader: (13)

I was going to remove the roll-over one, but am too lazy. Besides, the other two will still flow regardless. I'll get around to it some day.

It has a ball that rolls over and blocks fuel flow in the event the car rolls over. It's a safety feature.

I don't know if it's before or after the filter or pump on a 7.

The_7

i dont mean the roll over valve i was talking about the one in the evap line. or does that do the same thing?

Rx7carl

The one on the vent line keeps the tank from becomming positively or negatively pressurized. It vents at a very low psi in either direction but stays closed if theres no pressure on it. Its sort of an emissions device. Keeps fuel from evaporating like an open vent would. But also allows air in so the tank doesnt collapse if the outside air temp drops and the fuel contracts. Clear as mud eh?

The_7

ahh i c
thanks for the explanation carl
i think ill leave it on then

what about the rollover valve, mine is after the pump, should i rewire it to before the filter?

Rx7carl

I dont think it really matters to be honest with you. :shrug: