tap/die TII housing coolant passage
 

What size of a die do I need to do this? My dad is at work and has a nice set of tap/dies and if I can call him before he leaves to pick one up for me, what size do I need?
I don't want to seal them with glue, cause im gonna have to clean up the edges of the passages and it'll take a while, I just want to get a die in there, thread the hole and buy some plugs to thread em in with some loctite.

So, what size die?

also, what are the plugs called? so when I goto the auto store I don't sound like a dumbass.

thx guys!

Anyone? all I need is the die size in standard if possible!

once again thx for any input.

lol, I just called "rx7 specialties" and asked if he had any plug kits or something for the TII housings, these are the same guys that rebuilt my engine with the previous owner.

He suggested that I just buy o-rings and use the metal gasket and some crazy glue to seal the passages! So that means

LIM>Gasket>O-Ring>CrazyGlue>Housings

He said the pressure of the LIM to the block would seal the deal. This is EXACTLY how I found the setup when I ripped everything apart, and this is EXACTLY why I had little coolant pressure when hot and coolant loss in the first place!

His idea might work for like a year, but as I found the o-rings after I tore it apart, they were cracked and shredded up, making no more seal..

ugh..

ANyways I got my dad to bring home a few taps (he tells me taps are the ones that make threads in a hole, at least thats what I think he said heh..) and I'll just find the right one.
I might as well make a little article/howto when Im finished explaining exactly what tools/parts you need and the procedure.

Measure the hole, then select the tap closest to what you find. Or drill to one size larger, then tap appropriately.

Also, you want to pick up "grub screws" to block. Ultimately, you will probably need to let the size of grub screw available dictate the size you tap the hole to.

Where can I get 'grub screws'? Are they pretty much plugs with allen holes in them or something?

thx bro

Yep, that's them. Any fastener place will have them, as well as most hydraulic shops.

Princess auto is your saviour.

well, why would you tap the holes in your housings that plug right into the LIM?

aren't those that supply coolant to the turbo?

If you're using the housings on an NA engine...

ohhhhhhhhh shit, I know that N/A housing don't have these coolant passages, but I just didn't read his signature, sorry guys...

http://pengaru.com/~swivel/cars/rx-7...w_IMG_2785.JPG

thats what you want to do really, NPT hex socket plugs w/teflon on the threads. You want NPT plugs and a NPT tap.

Now, I wish I could tell you the exact size I used, I measured and had an array of taps and hex socket NPT plugs (aluminum) on hand.

Working from memory, it was 1/2" NPT. I'm not 100% sure that my memory is correct though :(.

Tapping that shit was a real pain in the ass BTW, NPT is difficult especially that size. I used aluminum plugs also because the housing is aluminum, I wanted them to thermally expand at similar rates.

JEGS has these, so does summit:
http://www.jegs.com/cgi-bin/ncommerc...27&prmenbr=361

your local speed shop might carry an assortment of these too.

FREZE PLUGS!!! no taping, no screwing, press them in or use a hammer.

Not a good idea, I started with freeze plugs, they leaked, and I graduated to the tapping and plugging. The problem with using freeze plugs is the inner wall of the port is not machined to recieve the plug, the bottom of the port has casting bullshit in it, the freeze plug gets bent and does not seal properly. I'm speaking from experience.

Mazdatrix recommended I use freeze plugs, they told me freeze plugs + epoxy, you're not supposed to use epoxy with freeze plugs, they said epoxy because they know it's not quite right. That is the ghetto approach IMO and much more likely to fail.

Nice Vito.

Well my dad had some grub plugs at work. He brought home a few bigger taps yesterday and one of them worked.
Basically I tapped out the 'inner' hole inside that water jacket. I can't remember the size that I used.. although I took a picture of the tap that I used. I'll post it later, I gotta goto work.

When he comes home with the plugs, I'll use some jb weld and thread em in and let that dry for a few days.

As for the metal filings inside the water jackets.... kinda unavoidable, I'll have to flush the system to try and get them out.

I'll post pics of what it looks like later with the tap size and the finished application.

I never tried the freeze plug trick, just relaying what others and Mazda trix has done. Personally I just used a metal gasket and the O-rings with no ill effects of over 4 years of driving. the absolute best though is tap and plug. YOU MUST USE NPT TAP, not just something the same pitch and diameter made for standard hardware. NPT threads are tappered so they seal more as you tighten them. JB weld is a bad idea for sealent in a wet and high temp situation. Use teflon tape or paste. If anything, high temp gasket RTV is better then JB weld. The JB weld hardens and cracks, you need somethign pliable.

~Mike........

Just a suggestion for getting the metal filings out, other than pressurizing the system with a hose or something and leaving the holes open that you just tapped, letting the spilllover bring the filings with... you can install a filter in your radiator hose inline, and leave it in there for a while while driving the car, it will collect the filings... you eliminate teh filter after it stops collecting junk (all clean). Mr. gasket sells a coolant filter that goes inline on your radiator hose, or you can make one yourself.