Hey guys just got a question on this, I have already read all the ast removel threads and websites, On how it say for a series 7 rx7 you have to either get a s4 waterpump neck filler or somthing if your waterpump isnt the one thats one hole bit, not like some how you can unscrew the filler neck bit, i was wondering it is the same if i remove the ast tank and just redirect the plumbing from the filler neck straight to the overflow bottle, would it be doing the same job?

 

No you would be putting pressure into the over flow and it would do just that over flow! If you want to delete the ast you need the fd filler neck that has the bolt on thermostat neck, then replace it with the s4 bolt on neck with the over flow tube built into it and run it to the over flow container. Also need a pressure rad cap for the pressure you need. One more thing is to make very sure you get all the air out of the system.

 

I c, so whats the difference with the s4 filler neck and the one on it now? wouldnt they be doing the some job if the s4 filler neck goes straight to the overflow or does it work differently? Ive got the s7 waterpump one where its all one peice so i would have to buy the other type and also buy the s4 filler neck so i can bolt it onto it?

 

The difference is the s4 filler neck cap has a nipple on it that the FD one doesnt. To add to what busted7 said, take the hose that used to run from the bottom of the rad to the ast, and run it instead from the bottom of the rad to the filler neck nipple. the other nipple, on the s4 neck, you run to the overflow.

yes, you'll need a two piece t-stat housing. I have a nice shiny polished one available if you're interested, PM me

 

Also if u r good in taping, u can tap the filler neck piece, I did that and my car runs fine with no issue's.
khris

 

Sorry forgot to mention the s7 housing was diffrent. Thanks mr goodfella! One tip i used to bleed air out of the system was to unscrew the temp senser and screwed in a barbed fitting and pumped a vacumn until i got fluid in the pump. Probely not nessesary but i wanted to make sure.