Okay, I did some research, so I know the primary function of the Sub-Zero Starting Assist Device is to help lubricate the apex seals in sub-zero temperature. I've also read how a lot of people removed theirs, due to them either not living in a climate that reaches that cold or because theirs never worked at all.

Is there a way to test the pump of the pump when the bottle and pump is removed from the car? I was doing some tinkering around my car, so I decided to remove it. I read the FSM about how to test it but that is a lot of hassle for me (seeing as how the valve is behind the intake plenum).

http://www.wankel.net/~krwright/file...ssions_13B.pdf

And, seeing as how I live in Virginia, where during the winter season, temperatures will probably reach below 32 degrees, I'm wondering if I really do need it? Actually, I'm not even sure if the think works properly so this is why I ask what is an easy way to test it? Oh, and I tried hooking up a positive wire and negative wire to the battery and "jumping" the pump. I got a couple of movements from the pump, but I figured that I wasn't doing it right.

Any help?

 

I would imagine simply applying power to the motor would be the test, but there is no need to waste your time. I removed mine years ago and It gets below 0 plenty of winter nights here in NJ and my FB's always start right up, and have been for years. I wouldn't waste you time with it if I were you

 

The only thing that stuck to my mind was that in one of the old threads someone said it was there to help with lubrication on the apex seals. I did a ghetto compression check today and got three nice even puffs on both rotors.

I'm just more concerned about the life of my motor. If it is nothing to be concerned about, then I'll go ahead and keep it out.

If I keep it out, what do I do about the hose that leads under the intake plenum and to that one switch? Do I go ahead and remove the hose, or both hose and the valve switch?

 

I always thought the sub-zero system helped boost cranking compression by injecting non-compressable liquid (water-antifreeze) into the combustion chamber to assist in extremely cold startups.Ive never heard about any apex lubing duties regarding that system,but I guess thats plausible.....

In any case,even Mazda saw fit to delete the entire sub-zero system right around the time the 2nd gen came out.Its probably not at all needed unless you live somewhere near Santa's workshop AND have a tired engine....in which case you should ask that jolly bastard for a new motor, for X-mas!

 

EDIT: After reading the rest of this topic link below (when all I see is "remove it, remove it", I found that it's okay to remove it. Lots of posts regarding this thing.

https://www.rx7club.com/showthread.p...+assist+remove

The 6th post down, the member says how it "helps alot with apex seal life if you are in around 30 deg or less weather".

This is where I got my information from (among a few other topics in my search). However, the coolant level in the tank is the exact same as it was 2 years ago when I got my car. So, I guess the pump thing doesn't work after all.

And, I found out to plug that valve. But, how in the hell do I gain access to it without removing the plenum?

 

Ditch it. First, it only operates (if it even works) in sub-zero temperatures (that's Farenheit, not Celcius). It was used to build compression for those really cold starts as Steve said. Most of us live in places where sub-zero temps are rare or never happen at all and those who do live in really cold areas notice no difference having the sub-zero system or not (although it is hard to tell if it was working in the 1st place).

 

I don't ever recall Virginia reaching that low of temperatures, and factor in that I haven't lost any fluid in the past 2 years I've had this car, I guess I answered my own question without even realizing it. Ha!

 

What if you lived in Colorado? Would it help then? Seriously? I know it gets freaking cold there and I am about to move there. Either with my 7 or one I am going to buy, would that actually help the cold starting or help the life of the rotors that much?

 

Well mazda may have a point.. or may not.. cause at around freezing my 1st gen takes 3-4 tries to get fired up without it.. it dosent work so i wouldnt know anyways lol..

Maybe someone should hook it up and see if it makes a difference?

 

64mgb has a working one and he lives in Iowa. Does that help?