AST delete question
 

So this might be a stupid question, I’m sorry if it is, but I bought an AST delete kit from mr Crowe, and correct me if I’m wrong but all I do it connect the nipple on the new filler neck to the overflow and the other nipple off the housing goes down the to radiator right? Also, I would like to replace the hoses since I’m gonna have them off and they are original. Can I just buy generic or is it best to buy oem? If generic, is it 3/8” ID? Thanks!

https://cimg9.ibsrv.net/gimg/www.rx7...e88b016c3d.jpg
The new FC style filler neck on top of the engine water pump manifold goes to the over flow tank. The other water nipples get blocked.
If it is off the engine, you can tap and screw in a brass plug.

Ok, what's the deal with that weird ass slinky radiator hose. I've not seen that before @cewrx7r1

Connect the 3/8” hose from the nipple on the radiator to the thermostat housing. Connect the overflow hose to the Filler neck.

Billet AST elimination kit. Air Separation Tank (AST) (93+ RX-7)

https://cimg0.ibsrv.net/gimg/www.rx7...cc28a64ac.jpeg

You can either run the hose from the bottom small nipple of the radiator to the nipple on the thermostat housing or cap both nipples. Running the hose is easiest since you can just re-use one of the existing hoses.

A rubber cap (like a vacuum cap) should NEVER be used to cap those nipples off. They will fail in short order. The picture Chuck posted of a hose with a bolt and 2 clamps is a great way to cap off the nipples, it's not sexy but it's reliable.

Best/most involved way is to cut the nipples off and weld up the holes. There's no going back with that method, though.

Dale

So running from the nipple on the radiator to the housing won’t hurt anything? Welding isn’t a viable option for me, and I always feel comfortable knowing modifications are reversible. Is there a generic hose I can get? That’s reliable and durable

https://cimg0.ibsrv.net/gimg/www.rx7...046863485.jpeg
I ended up grabbing the nipple with pliers and ripping it out. It’s a press fit. I tapped the hole and installed a plug.
Matt

And now you still need to deal with the one on the radiator. Install loop line problem solved.

Sounds like it might be too late, but that billet neck from Banzai is the shizz. Barbed fitting, durable 'O' ring....and it's prettier. :)
I'd had the S5 plastic OEM filler neck for about 9 years, which was probably a few years past their safe expected life-span. His billet neck won't be prone to catastrophic failure.

pros and cons about deleting the AST?
last i heard it was a pain in the ass to burp the system OR it becomes problematic with overheating issues?

^ Not sure where you heard that. I change coolant annually. Takes maybe 30 minutes including burping. Has had absolutely no perceivable effect on temps.

I use a Lisle funnel on every car, regardless of AST installation. It makes burping the system effortless

I changed the temp sensor on the back of the housing a while ago and the add coolant light /buzzer came on and no matter how long I ran it or burped it (with lisle filter), it remained on and the overflow tank was overflowing, so I decided to change the radiator (old one was very questionable) , delete the ast and change the rad hoses as well. I could be calling this the wrong name, but I saw where people fill it until it comes out of the throttle body hose as well? Can someone explain this a little more and maybe add a pic? I’m trying to eliminate the possibility of it being a circulation issue, and narrow it down to maybe a wiring/ground issue

Sounds like your low coolant sensor might be bad. It's a cheap part and they don't fail often but they do fail and cause you to panic for no reason. Replace that first.

I already have all the other stuff, it’s still apart, I’m waiting on rad hoses from mr Crowe, maybe I’ll tell him to add that in there as well lol the other stuff prob needed redone anyway, it was all original and didn’t look so hot

Theres a hose on the firewall side of the tb that runs down to the engine. I just pull the end off the TB and fill with it off. Dont always get coolant there but definitely hear air escaping from it while filling. Ive done this 4 or 5 times now and havent had any trouble with air pockets in the system. I also use the lisle funnel.

Ok cool, I know which one that is, thank you, I’ll do that

Replaced the coolant sensor and no more buzzer 👍👍 thanks for the input

Banzai billet piece looks nice. I need to do this, thanks for posting.