87bucket

i own a 87 non-turbo rx-7. i started noticing that my 5th and 6th ports might not be working. i tested them and sure enough they were not. i took the actuators off and found out that the valve that the actuators connect with stuck and wouldn't move. i cleaned them up really good and they now move freely and properly. i also cleaned the actuators and they also pump freely. i assembled everything back together and i tested them again and they still didn't work. i am confused on what else to do. i would appreciate any advice on what else could be wrong.

idsigloo

Are you using aftermarket exhaust? The s4 5th/6th ports are operated by the backpressure in the exhaust. Usually with aftermarket exhaust there isn't enough backpressure to operate the ports. Your only choice is do a search for air pump actuator mod where the air pump will open and close your ports for you. GL.

Syonyk

The seal between the lower intake manifold & the 6th ports is rather difficult to get to seal.

Get a length of vacuum tube, put it on the nipple feeding the ports, and blow. You should feel quite a bit of resistance, and be able to open the ports with your lungs. If you can just blow through it and the ports don't open, it's a sealing issue. Pull the actuators off, clean ALL the old gasket material off (carb cleaner is a wonderful gasket removal aid) both sides, and use a thin layer of RTV to make a seal. Be careful not to block the actual inlet hole on the actuator. If you look at the manifold, one side has a hole, the other is just flat. Feel free to RTV up the flat side quite well, blocking the hole in the actuator doesn't matter, but on the side with the inlet hole you need to be careful.

-=Russ=-

87bucket

i do have a racing beat header and full exhaust and i removed the air pump. i also do remember that gasket on the actuator is torn apart and hardly even there.

87bucket

where is that nipple feeding the ports?

nopistons

The key is: Do you have a cat? If you're not familiar with the stock system, there's a tube connecting backpressure in the cat to the 5 & 6 actuators. If you have no cat backpressure (S4) to feed the actuators, they aren't going to open. You'll have to use another method, which can be found by using Search. There are a couple of ways to do it.

jgrts20

he has an AFTERMARKET exhaust, do the electric port conversion like I had t0. They work awesome that way, then you will never have to worry about backpressure and sh^t.

87bucket

how do you the electric port conversion? what other methods are there to open them up?

jono20

air line directly off of the stock air pump

87bucket

i took off my air pump when i installed the exhaust. is there another way to open them up?