Manifold to turbo bolts coming loose?? WTF?
 

So i developed a small exhaust leak last week and found it to be the 2 bolts on the right, top and bottom (if facing the turbo/mani) were loose. No problem, just fight with the FM heat shield like there was no tomorrow and tighten. Then fight with the FM heat shield again to get it back on. Done.

Well i just came back from lunch and opened the hood to hear the same leak AGAIN! Is there a way to combat this? Safety wire? Suggestions?

Call up FM and order up some stover nuts and nord-lock washers.This combo with never come loose.

If you wanna go extreme you could go with stage8 fasteners.

Nordlock washers. I was able to get mine by mailing the Nordlock directly and asking for a sample. Or you can buy them from FM. :)

I think I'm gonna try that next time I need some.

Thanks for the tip Jay.

yah... on i'll call FM and hope they send me the right stuff. Who knows, maybe they'll goof my order and send me a turbo kit instead lol.

Don't buy that shit from FM. They charge some retarded amount of money. Get them at Fastenal: http://maps.google.com/maps?hl=en&um...e-results&cd=1

I call bullshit on the FM washers. I've had crazy problems with fasteners on mine rattling loose. On my previous setup I was rocking FM washers (thanks SamNavy) with the threaded nuts. They held for longer then the regular nuts and locking washers, but last week I realized one was missing and had managed to backthread off completely! I eventually will need to move to the wire locking setup or just start nitching my threads lol.

They worked well on my Greddy kit, with 3/8" exhaust manifold studs.

How much are they from Fastenal?

If these are the same, they're pretty inexpensive

McMaster-Carr Part No. 93795A240
Class 8 Zinc-Plated Steel Conical-Top Locknut Hex, M10 Screw Sz, 1.5mm Pitch, 17mm Width, 10mm H
In stock at $4.52 per Pack
This product is sold in Packs of 25

weird. I use the 80,000 mile stock exhaust nuts with no problems.

That be the nut, not the washer.

i just use plain ole lock washers

Don't most 10mm nuts/bolts have 14mm heads? Is it tough to tighten those Mcmaster nuts since the head is 17mm? On my GTX I had to grind down a closed-end wrench to get to one of the turbo nuts.

Anyone tried SS nuts like Corky suggests?

Safety wire. There's a reason high-reliability systems use it (look at any airplane or helicopter).

I used safety wire on my current BEGI system and after 3 1/2 years and >60,000 miles I KNOW the studs and nuts haven't loosened.

Stover nuts or equivalent on the studs works great until the studs back out...happened to me on my last setup and I ended up ruining an exhaust manifold. Yes, I realize that if the studs are torqued properly the studs should not back out. If the nuts are torqued properly they should not back off. Coulda, shoulda, woulda. $500 for a manifold...safety wire and drill bits are a heck of a lot cheaper.

Just do it. It only takes an extra half-hour.

Barry

^I'll buy that, nice first post.

This is another good thread I started... check out Post#32. I had enough leftover that I even mailed a couple sets out to dudes for free after that.
https://www.miataturbo.net/forum/sho...light=nordlock

Oh, ah, so the stud and the nut are wired?

Wow that sounds like a good idea. I really loved my nord locks, for a while... In theory they would hold the stud in too. :-) But after a couple uses they don't always hold - there are two kinds and I think I have the cheap ones. Fm sells the "good ones" for a whole lot more, I doubt it's justified, but I will admit mine are worn a bit flat.

8mm studs dont even stay in the manifold, and if they don't back out they crack.

Get 10mm studs and be done.

If I ran the universe there woudln't be studs, there would be nuts and bolts. Those always work fine, and gives you a lot of options for locking

To safety wire the studs/nuts do you have to drill a hole threw both? Pictures please. :)

Did you try tack welding???

You don't need to drill anything, they make a kit that uses washers you fold up and has a tab you run the wire through. Check out this thread post 6 for the kit. ;)

https://www.miataturbo.net/forum/showthread.php?t=16683

Mine started to back off once when I had a POS gasket. I removed the gasket since both flanges were flat and torqued the nuts ~60ftlbs and they haven't moved since. I think the gasket was the problem.

uhh... i skipped ahead because im trying to take a 30 second study break.... but have you tried "Thread Locker" yet?

mine stay put with rust

Thread locker will burn off.

I had nothing but trouble with the Nord-locks and studs. I put some bolts in it with the Nord-locks, hasn't budged. I would try ditching the studs.

Nordlocks and crimped nuts worked perfect for me. They were just so DAMNED hard to get off. The GT28 and FM manifold are impossible to deal with, so it's a trade off between nuts staying on and nuts being removable. A bolt just won't fit. Washers and tall nuts don't really fit. The whole thing sucks ass, honestly.

Your link went back to this same thread?

Anyway, if you only hold the nut, it seems weird the stud couldn't come out, but I guess it just wouldn't come out easy.

Well, it seems that we have all tried various things and have different conclusions lol

Well, im going to try some lock washers first and see what happens. If that does not work, then it'll be the nord-locks.


After tightening down the bolts the other day and installing the heat shield, i have noticed a heck of a vibration coming from somewhere at part throttle.... might be the heat shield, but its driving me up the walls :( There is quite the design flaw with the FM heat shield and the rear mounting point (also hold the ground strap) in that it LOVES to get it on with the heater hose when trying to lift it up. I wonder if FM likes re-design submissions lol.

I had locks washers and studs and lost two nuts and a stud this past summer.

Regular lock washers will not retain their spring wth the heat. After only a couple 1000 km mine were basically flat washers.

Lol I can attest to that shit. Another thing that was funny was the heat fused my nordlock washers to my nuts.

Yea, did you see post 6?

What's with the weird tool in the kit? It sure does seem worth it though.

nm

It's used to twist the wire together to tie it off...like a twist-tie.