19rxseven87

Hi guys, (87 TII with jdm 13b-t)

I was wondering if someone could educate me on what the check valve does on the turbo inlet. I understand it's a one-way valve which doesn't let air pass one way but will the other way, but I am wondering what function it provides for the car. My car has been undergoing a major tune-up including some minor mods, and I seem to have misplaced the check valve while installing the corksport turbo inlet tube (meaning the check valve is not there, I'm not quite sure where it is actually).

Which direction should the air flow? Should air flow away from the inlet tube? Meaning no air can pass into the turbo inlet but can pass out?

The car has been taking forever to start, it will just crank over and over for around 1 or 2 minutes before it decides to start, and when it starts I can shut it off and turn it on again fine. Before it was having a problem trying to crank over, but that turned out to be the starter harness, which I fixed with a new harness.

I am wondering if installing the check valve (which is supposed to be there) would help cure my cold start problem? Before the major tune-up the car would start fine, just the starter would be a PITA to crank (again, because of the then-bad harness).

TIA. much appreciated.

AGreen

iTrader: (11)

It's for the "crankcase" ventilation. If there's an open hole in the intake anywhere between the afm and throttle body, your car will have a hard time running, especially on cold starts. Many people throw it away and plug it, I don't recommend doing that unless you figure out some sort of other system for removing the crankcase vapors. It can make your turbo smoke and seals blow out prematurely if you don't do anything about it.

19rxseven87

does.the direction of flow of the check valve allow air into the inlet tube but not out?

Aaron Cake

iTrader: (1)

I hate to say it, but you can find all this info in the FSM.

The Factory Service Manuals for all years of RX-7 (and many other rotary cars) can be downloaded for free here: Foxed.ca - Mazda RX-7 Manuals . They contain all common service information information and more, and are an essential tool for any sort of service work that needs to be performed on these cars.

Additionally, the Haynes service manual for the 1986 thru 1991 RX-7 (both turbo and NA) can be found at most local auto parts stores or purchased from any good bookstore (ISBN number 1 56392 007 7). It is only about $25 and is a great quick reference for things like this. Not only does it contain most of the information in the FSM condensed into an easy to read format, but it includes full wiring diagrams as well.

These manuals will answer 99% of service related questions for the car and if you intend to do your own repair work, you will need at least one of them. Preferably both, since the FSM is a free download. The Haynes is a good quick reference covering 99% of questions, while the FSMs show complete and detailed procedures.

19rxseven87

thanks, looked at it and helped a lot however i.couldn't figure out the direction of the air flow? is it blocking flow away from the inlet tube or into it?

AGreen

iTrader: (11)

In. It's supposed to suck the crank case vapors out of the engine.

19rxseven87

thanks much appreciated