im doing the y-pipe installation and cant seem to get the intake pipe off for the life of me. the car is jacked up but i cant get to either of the bolts because the precat and heat shield is in the way. also how will this help me get the y-pipe out?? the top inlet pipe is the one that everyone is saying to remove right? .... but that doesnt connect to the y-pipe, its the bottom outlet pipe that keeps the pipe in place. anyway, i cant seem to make any progress and i need to finish all this by hte end of the weekend.... please help me someone!!!!! thanks

 

https://www.rx7club.com/forum/showth...hreadid=213366

 

Stop goating JON "Tiny Arms" SKI

 

ok is it the 'inlet pipe' or the 'outlet pipe' that needs to be loosened? i read the post but i still dont know how you did it....... there is a metal hose (i think the fuel line) that is in the way of my ratchet, anyway the precat is in the way. can you be more specific?? thanks

 

That metal pipe that connects to the firewall side of the LIM is the air pump feed to the main cat. You need to remove the rear (secondary) turbo inlet so that you can you can remove the charge elbow (two 10mm nuts) along with the y-pipe (also two 10mm nuts).


I don't think you can get a good look at the two nuts holding the rear turbo inlet, but if you reach between the ABS and the inlet you can feel them. You'll need a small ratchet with a two inch extension (if you don't have an extension, then I think just a deep 10mm socket will work). You'll only be able to fit one arm back there at a time, and unless you've got beefy arms, you should be able to stick a ratchet on them and break them loose. After they are loose, just turn them off by hand.

 

I didn't have to remove that at all. The studs on the primary compressor housing came off when I took those nuts off. If they're loose enough, take those out and the y-pipe will just come forward. Done!

 

I like the idea, but if the studs don't come off with the nuts then there won't be enough room to double-nut them (heh, that always makes me laugh) and you'll need to use vise-grips that will tear up the threads. You could just replace the studs with some bolts, just make sure you don't use stainless steel ones or you'll risk galvanic corrosion on your y-pipe and compressor snail.

 

done!! thank you SO MUCH for walking me through it jonski!!! i could just barely fit a 10mm straight wrench behind the cat. you always give detailed explanations for how to's...thanks again! i ended up spending a day cursing my fd and i feel that i will have another such day tomorow (these cars dont seem to be designed to be worked on). so now that the y pipe is done i have one last question before i can start putting everything back together: how do you get to/replace the two vacuum lines that dip down under the solenoid wiring harness to the LIM? they are in the attached picture... i cant even see one of them stops and it seems nearly impossible to get to.

 

It's difficult to tell from your picture. It could be either the rear oil injector or the fuel pressure regulator feed. You could remove the ACV (Air Control Valve). That's the big thing that's above your arrows. There are three nuts holding it on. The two at the top are easy to spot, but the third is directly below the top center one. Just feel underneath the ACV to find it. Once that is removed, the job gets way easier.

 

the hoses actually run underneith the wiring harness and then down... the wiring harness doesnt seem to move more than an inch and im not sure that there is any other way to replace these. it sucks cause ive come this far but now im stuck on these 2 little hoses... does this picture make any more sense? i think most people would remember this point in the vacuum line install cause it seems to definately be the hardest part of the job.

on a side note: the bolt idea is a great!! anyone removing the y-pipe should consider this! by the way, jonski, what was that about stainless steel causing galvanic corrosion and what exactly is this type of corrosion?

 

I think the arrow that goes up and points to the left is the vacuum hose that connects to the Fuel Pressure Regulator solenoid (labeled (A) in the diagram). The other arrow probably goes to the rear oil injector.


If you are doing a hose job, then be sure read these threads as well:
https://www.rx7club.com/forum/showth...hreadid=129174
https://www.rx7club.com/forum/showth...hreadid=167287


I don't know the chemistry behind galvanic corrosion, but basically:
stainless steel + aluminum + water (or high humidity) = aluminum oxidation. In case you need to use S/S in Al, you can buy sealant that prevents water from getting in. Otherwise, the threads will corrode out of the aluminum and you will need to re-tap the hole. Aluminum oxide also makes it really hard to remove bolts.

 

ok i finally gave up and un bolted a bunch of crap from the LIM to get to the hoses... well it took a LONG *** TIME, but im just happy its done . Thanks again jonski! tomorow everything else will go back in and i will have a kitchen table again. oh, about the corrosion that we were talking about before... is it always triggered by s.s. or can it be caused by other things? ive noticed on alot of the older fd engines there seems to be white spots on areas like the UIM and such. theyre starting to develop on my car and it looks like crap (like the engine is moldy..haha) i was under the impression that aluminum was not so prone to oxidation. anyone else getting this? also any one know how to stop/reverse this process? peace homies

 

Oxidation happens naturally, but S/S speeds up the process. I wouldn't worry about natural oxidation, though.