So,

I just purchased a radiator cap from Ray@malloy, the one for the filler neck.

It was described to me as a non-pressure cap; However, the cap I'm using right now(the one that was on it when I bought the car) has an extra plug type thing on the underside which my guess--IS pressure.

Ray told me that the pressure caps are used for the AST. Why is the one on my filler neck pressurized? does it have anything to do with that recall?

Which one IS the proper one to use?

school me, please

 

it should have the flip top for the AST and the regular for the filler neck.

AST:
http://www.rx7store.net/product_p/pettitast.htm

Filler neck:
http://www.rx7store.net/product_p/greddyradcap.htm

 

well I mean, the one that ray sent is just a regular cap metal cap

the one installed now has circular rubber piece connected to it (on the underside)

am i supposed to transfer that piece over to the new cap? what am i missing?

sorry, i know its something stupid/obvious

 

sounds like the ast was removed and he presently has the 86 cap with the overflow....

does it look like this?

 

n0pe...

I'll take a pic this weekend...i wonder why mine's so weird..

 

The stock AST and filler neck caps are not vented. In fact my AST cap doesn't even have ears on it.

Dave

 

[QUOTE=4CN A1R;7972707]sounds like the ast was removed and he presently has the 86 cap with the overflow....

does it look like this?

actually, i took another look and I think you're right

here are some pictures--I realise now mine doesnt have 'ears' either..











what type of cap is this? should I just take it off and use the 'normal' one I ordered from Ray?

 

As 4CNAIR suggested, it appears a previous owner has deleted your AST and added the black portion to the top of your filler neck. It's difficult to tell for sure, but the nipple looks like it was at least partially broken off. Normally a non-pressure cap is at the filler neck, but with the modification, a pressure cap (one with a spring pressure release) needs to be installed.
Read through this and it might explain what was done by the previous owner, and what you need in terms of caps.
http://www.rx7.org/Robinette/coolant_tank.htm

 

Hmm...I have a Pettit metal AST, that the previous owner installed, not stock anymore.---would I still need the pressure cap..?

 

yea u need 13lb on your at and no pressure on the neck.

nothing leaks out of the upper hole right? the one right under the cap on the neck.

 

nope, never....

SO wait, this pressure cap was on here for no reason??


i can take it off and replace it with the plain-ol regular metal flat cap with ears?

i wonder if using two pressure caps has caused any harm...=/

 

Is that nipple blocked off in someway? If not, then NO, you can't replace it with an unsprung cap. And even with the pressure cap, if system pressure ever exceeds the cap's rating, then you will loose coolant out of the open nipple. If the nipple is blocked off, it's still a potential failure point that should be removed. If it were my car, I'd double check that the routing is proper to the AST and overflow tank, and replace that filler neck with the OEM piece (no nipple). THEN you can install the non-pressure cap that you got from Ray.

 

why not just keep it the way it is now? just run a hose from the overflow on the cap to the reservoir.

 

It looked to me like someone had sawed most of the nipple off in the earlier picture. Too much to put a hose back on.

 

yeah, and when i look in that 'hole' it does seem to be blocked off....

And the AST is routed properly----this is mind boggling though, because there was a stock AST on the car with the previous owners, and then they replaced it with a petit AST----they never eliminated it (as far as i know)...not sure why this cap was installed at all.



I'll order the original filler neck, does it have a special name or P/N ?


thanks for all the help yall!!

 

I'm not sure how much they cost new...guessing < $35. I think the part number is going to be N323-15-175. There's an O-ring (Part #N326-15-174) under it, that can probably be reused. Call Ray @ Malloy, he'll know.
You can also try posting up a WTB (What to Buy) in the parts for sale section.

 

turns out i just need the new filler body to go with my cap

thanks for the help everyone!