Downpipe bolt is missing again.........What to use

[Florida240sx]

Leaving to go to Nopi and 2 of my 4 downpipe bolts are missing...Been driving for over a year and never had a problem....Go and get osme replacements.... Buy threadlocker while I was there too...Install them and drive to nopi.....On the way back I feel a powerloss as some honda tried to pass me.....he still lost Stop and get gas and one of them is missing again....Put another one in and drive 120miles home.... While on my backroads I open her up once or twice and something is wrong.....Pulled in my driveway and it's missing again....What should I use to keep this bolt in my turbo....It's about 3/4" long goes through the downpipe flange and scews into the turbo...... On all my other bolts that I have had problems just used gasket maker and they have hold....but this is in a high heat area..... What do yall use/recommend????

[enigma2103]

hi-temp silicone?

[SeanC]

get the wrong thread pitch and cross thread! j/k

get some split lock washers and allen head bolts. thats what i use and it works great.

[j-z]

lock washers mang

[C-Kwik]

Being that it's a part that sees a lot of hear split lock (spring) washers may lose their spring and essentially become a flat washer. Try a mechanical locknut. Not the ones with nylon inserts (it may burn out) but the ones where they slightly bend the top of three sides of the nut inwards. OE's use this type for headers and such. The need for this type of hardware depends on how much heat they will actually see, but it's better safe than sorry. I used them on all manifold connections, and on the turbo to downpipe connections. You can also try serrated washers, but my own experience with them reveals they only delay the hardware coming loose.

[Florida240sx]

lock nuts wouldn't work unless I put a bolt into the turbo and then used a nut... I got gasket maker in the threads right ow....see how long it will last

[hek1620]

my dp bolts and mani bolts used to come off all the time. but that was because the whole exhaust was being held up by a hanger at the muffler and the down pipe. once i had some hangers installed it stopped spitting them out. check it out.

[Florida240sx]

It's been fine for a year and then all of a sudden.... Exhaust has never ratteled

[EazyBreazy]

put two nuts on the bolt, screw the first one down and tighten it, then screw the next one down and tighten it against the other bolt

[Florida240sx]

My turbo does not have studs that come out of it...I put my bolt through the downpipe flange and the bolt screws into the turbo....

[C-Kwik]

Ah. I had an on-center T4 that wasn't threaded so I had a bolt/nut arrangement. You might try switching to studs so you can use a mechanical locknut. When a stud is torqued down using a double jam nut method, it will not vibrate loose. Note that studs for the manfold to head connection and typically, turbo to manifold connections use studs and they don't usually come loose.

The gasket maker will likely burn off.

You can also try finding bolts that come drilled for safety wire or make your own. I made some using allen head bolts. Using a piece of angle metal, drill a hole through it sized for a tap that matches the bolt's threads. Tap the hole accordingly. Then screw a bolt in until it seats. Clamp the angle to a drill press so that the bolt is perpendicular to the drill bit and drill a small hole through the side of the bolt head. The bolt head will need to be thick enough (which is why allen head bolts worked for me). You can make several very quickly by only removing the bolt from the angle and putting a new one in. Use the bolts as normal, but when everything is tight, use safety wire through the holes and lock each one to something so that it prevents it from unscrewing itself. If you think it out properly, you can use one wire and arrange it so that any bolt that wants to come loose would tighten another bolt. The easy way would be to use one wire for each and wrap it around the downpipe. To tighten the wire, twist them together. To get it really tight, put the ends of the safety wire in a drill and pull the trigger. It will twist up uniformly and make it easy to cinch it down. Don't over do it as it may break the wire at the base of the twisting.

there are also some bolts made for exhaust manifolds and such. They are pricey, but effetive. Stage 8 is one company that makes these.

http://www.stage8.com

[Florida240sx]

Good idea using a stop washer with a c-clip on it..... Goign to try a couple more thread lockers before I go with studs.... I have bad luck with studs breaking

[S13FX]

Dude just duck tape it and you should be fine

[C-Kwik]

If you're planning to use a threadlocker like loc-tite, don't bother. It will burn off with the heat the hardware will see.

There is an interesting bolt I have heard of. I found it in my search of a solution years ago. Unfortunately, it's damned near impossible to get....unless you're willing to buy in bulk. It's basically a bolt with a stainless steel insert in it. The insert is basically a rod that goes through the threaded area of the bolt. Stainless steel expands more than regular steel so the insert essentially locks the bolt in place when hot. I don't remember what company makes them and their site didn't advertise them, but I had learned of them when I called the company about a solution. They are in the socal area and the sales rep was going to try and score me a few since there were no distributors selling these items(they generally sell these straight to the factories that want them). Unfortunately, I found a solution before I got a chance to see him and lost the info.

[nissan_blood]

Dude just duck tape it and you should be fine

Come on now. Duct tape isnt JDM tyte he would have to use zip ties. Think man jesus

[scarboroughdub]

all ideas are good, but what i do is i put a small tack of weld on the nut, this prevents it from loosening but is breakable when removing the nut.

[hek1620]

if only everyone had a welder.

[Florida240sx]

It would be better jsut to put some jb weld on it instead of a tack weld... Bolt is so small that you could ruin it quickly.....But what I have is bolts not nuts....I don't have studs and then nuts to hold it on.....Gasket maker is holding up so far.....

[hek1620]

where is the first hanger on ur exhaust after the d. pipe?

[Florida240sx]

Where the cat would be......Problems have been fixed by my gasket maker , I was just seeing what everyone else was using to cure it....

[wcbjr]

http://www.crucialracing.com/p...e.php

[Florida240sx]

Gasket maker held up fine @ 12psi.....Then cranked it to 17psi and it disappeared....Current product being used is electrical tape He held for 120miles at 17psi Let's see how long it last....Next will be copper gasket maker

[steve s14]

i use high nickel studs with copper nuts and they seem to be holding up fine.

[hek1620]

damn that must look good.

[DammitBobby]

I found this on saab site. Mate the downpipe to the turbo and fit new nuts. These should be copper, self-locking nuts as supplied by Saab (the original nuts might not look like copper, but they turn black with seconds of running the engine). They have a crimp at the top of the nut. Steel nuts are not suitable, as they will quickly loosen due to the intense thermal cycling, even if spring washers are fitted.Torque the nuts as near as possible to 25Nm (18lbft).

I think these will work?

http://www.atpturbo.com/Mercha...e=FST

[WDRacing]

Lockwire nutz work best.

[eazye2000]

I found this on saab site. Mate the downpipe to the turbo and fit new nuts. These should be copper, self-locking nuts as supplied by Saab (the original nuts might not look like copper, but they turn black with seconds of running the engine). They have a crimp at the top of the nut. Steel nuts are not suitable, as they will quickly loosen due to the intense thermal cycling, even if spring washers are fitted.Torque the nuts as near as possible to 25Nm (18lbft).

I think these will work?

http://www.atpturbo.com/Mercha...e=FST

Dude, those are exactly what I use on my T2 bottom mount. I use them with regular washers and they don't back off.

[DammitBobby]

Lockwire nutz work best.

I agree but it will be impossible with my setup to use that method.

Eazye2000!Thats what I wanted to hear that will be the best solution for me. Now I got to figure out if I can thread a bolt from the bottom and use that to lock it down or if I have to use a stud.

[eazye2000]

You let me know if that's what you wanna do. And if the thread from the nut is the same in your turbo, that would work out great. As it is in my case. If you have a different sized thread in your turbo and can't find a nut, let me know because my parts store has alot of double-threaded (<--is that a word?) studs with a few different combinations. Grade 8 or 8.8, whatever that class is. Just let me know, I don't mind helping anyone out. BTW, mine are M8x1.25 x 35mm in length.Oh, they used to have that same nut and stud at Autozone, but for some odd reason they discontinued it. I'll call my buddy at AZ and find out what the number used to be for them so you can go see if they still have any left over.

[DammitBobby]

I just finished tapping my manifold to 10mm 1.5 pitch. The downpipe size is 8mm 1.25 pitch. Yea let me know about the part numbers because I want to order the hardware Monday if they don`t carry it anymore.