ThePass

iTrader: (3)

Parked my miata like.. two months ago because motorcycle weather is in current effect and figured it would be a good time to pull the turbo off and swap the old turbo to manifold bolts with the new ATP Turbo studs and fancy shmancy locking nuts and washers. Went to do it today since weather is getting cooler.

So I put two nuts on one end of the ATP stud, and with the wrench on the top nut butting up against the second nut below it, cranked the stud down into the manifold. It took quite a bit of force on the wrench to get the stud all the way in. Once it was in, the top nut came off easily but the second nut that had been under it seemed jammed on. I kept loosening it with force and it seemed like it was almost stripping the stud as it backed off it. After travelling up the stud maybe 1 mm, as I turned the wrench the nut broke the end of the stud clean off.

I tried to put two new nuts on the remaining threaded portion of the stud so I could pull the broken stud out of the manifold, but it is so firmly in the manifold that I ended up rounding off the nut before the stud would budge.

So, now I have a manifold with a broken stud sticking out of it, and a rounded off nut under another nut on the stud.

Frustrated. In retrospect, I have no idea why it so much force to tighten the stud (which is an 8mm 1.25 pitch stud) into the manifold - I think because of how much force it took to tighten it, the nuts squished together with such force that the top nut deformed the bottom nut and messed its threads up...

Anyways, just had to rant.

ThePass

iTrader: (3)

Just tried to vice-grip on the nut and loosen the stud but to no avail, the nut is literally pulling the nut above it off the stud without backing the stud out.

So now I have to get a new manifold...

8mm x 1.25 pitch is the correct size for the greddy mani yea? I'm 99.9% sure it is. I think the damn thing is just so old that the threads in the mani aren't as they once were... otherwise the stud should have just threaded right in..

wayne_curr

iTrader: (8)

new manifold my ***. Drill and tap that **** out to M10 studs.

SKMetalworks

iTrader: (7)

+ 1

Drill and tap cost ya 30 or 40 bucks.

new manifold atleast 100 ish.

Jeff_Ciesielski

iTrader: (10)

Drill and tap + helicoil. Prevents problems like this in the future, and according to Mr. Bell, provides a better/stronger grip for the stud.

Edit: Pacific NW FTMFW on this one :P

ThePass

iTrader: (3)

All right, Washington for the win. Sign me up.
So, I gotta find someone around here that can drill/tap/helicoil my manifold for 10mm studs. Will be making some phone calls...

curly

iTrader: (25)

I thought you weren't supposed to torque the stud down. My original greddy studs were a bitch to take out, I barely got them with a combination of the double nut technique and vice grips, ruined all the nuts and studs by the end. I replaced them with allen bolts though, so I'm no help.

ThePass

iTrader: (3)

Original greddy studs? I didn't think there were any studs used in the original kit - all bolts. When I bought my BEGI downpipe it came with studs and nuts to replace the turbo to downpipe bolts and I am now converting the manifold to turbo bolts with studs/nuts..

As to not torquing studs in... I think a combination of having a cast iron mani that's probably been around for as long as many miatas and the fact that I pulled the turbo off like a month ago and the mani sat there and probably formed a bit of rust inside the threads contributed to the fact that I could only get the stud about one thread in by hand and it got progressively harder the farther in it went..

-Ryan

Reverend Greg

iTrader: (3)

It is common shop practice to chase the threads with tap before attempting to install studs in an instance such as this.The helicoil will only complicate matters in this case drill and tap them and install new studs,yourself.If I have to PM me for my phone # and I will walk you thu it.
-G-

hustler

iTrader: (6)

where is the part about using anti-seize or a lubricant in general? Oh yeah, you haven't done that yet.

don't use the pincher nuts, lube-up the stud, put anti-seize on the other, and win at life.

curly

iTrader: (25)

After you chase the threads of course. Go very slow, you'll easily break a tap chasing the threads. Dunno about drilling and taping for M10, could be soft or hard, no idea.

gospeed81

iTrader: (51)

Best way to do this is to come back a few turns after every full rotation into "unclean" thread you make. This applies for a virgin tap and rechasing. The shavings built up at the cutting edge, and can cause enough friction to break the tap (as well as hardening/dulling the working edge).

Reverend Greg

iTrader: (3)

+1
It is no problem to tap cast iron,lots of lube is all.
-G-