How to get bolts to not vibrate loose...?

[Mahonroy]

So I have these bolts on my turbo manifold that hold down a heatshield and they always end up vibrating loose (M8 bolts with a lock washer, I've tried using some locktite on them which only helped a little).

I also have these nuts that bolt the turbo to the bottom of the turbo manifold that also vibrate off (M10, no lock washers or locktite).

Last I have nuts that bolt the downpipe to the turbo, also M10 w/out lock washers or locktite that vibrate out.

Anyways I am wondering what is the proper way to secure these so I don't have to worry about them anymore? The nuts I have been using are steel that are zink coated (which obviously the zink coating burns and flakes off). Should I use a different material? I've seen people use copper nuts for stuff like this. Or is there somekind of a locktite I should use?

Anyways yeah just looking for some tips on how to keep these things secure and not have to keep replacing them. Any help is appreaciated!

[KeWLKaT]

Forget loctite. Too hot.

Lock washers are the key here. Try different ones. You need to get them to score the surface really well.

[only1db]

i have found that using brass( or copper even?) with a lock at the end of hte nut has helped...

i dont know where they got them from or even what the proper name is...

but at ther end of the nut it has a slice in it and its bent down....so when you tighten it down it essentially locks itself on there

we used them on a wrx motor...that we put in a van.

locketite will not work....it just gets too hot.

[tharptroy]

perhaps safety wiring is in order.

http://www.ultralightnews.com/pilotslounge/safetywire.htm

http://www.whizwheels.com/Tips/safetywiring.html

[KeWLKaT]

perhaps safety wiring is in order.

http://www.ultralightnews.com/pilotslounge/safetywire.htm

http://www.whizwheels.com/Tips/safetywiring.html

Yeah but it looks ugly on the heatshield :abovelol:

[tharptroy]

oh, come on felix...I didnt know that we were entering a fashion show...just safety wire 50 cents car, and a few other posers, and you'll have every ricer creaming their panties when they see wire on your car

[dmdicks]

brass lock nuts are the best. You can get them from Ace Hardware. The nuts themselves actually deform when you tighten them so they can't come loose. That's why they are a one time use only nut.

[KeWLKaT]

oh, come on felix...I didnt know that we were entering a fashion show...just safety wire 50 cents car, and a few other posers, and you'll have every ricer creaming their panties when they see wire on your car

:abovelol: :abovelol: :abovelol:

:nosthumbs True, true.

[Mahonroy]

Well I called around, called a couple ace hardwars and the only brass locking nuts they have are standard, no metric.

They refered me to this place called "AAA Metric", they have the brass nuts, but just normal ones, non locking. Do you think those would work? Or work along with a normal lock washer?

[KeWLKaT]

Why are you looking for nuts?

Ah.. the downpipe.

Well I replaced my studs with bolts on the downpipe if it helps, with locking washers. Never vibrated out since.

[bmxdad]

There are a couple of different ways, depending on if your talking about a nut or bolt.

For the bolts there is a one shot thread available. It should be available at a large fastener outlet. It has a special tooth profile that allows the bolt to only screw in one way ... kinda drastic, but its there. You need to break the head off to remove the body ... which means no blind holes. They usually have a hex hole in the end for this.

Another thing you can do is an old machinist trick. Drill a small, #30 or smaller, hole between two threads(into the root of the thread), about twice the threads height. Then press a piece of brass rod into the hole and locktite it in place. Use a diamond or knife shaped file to rough it down to the threads profile, but leave it proud, about .005.

For the nuts, get a sharp punch with a diamond shaped tip, and put a good mark in the body of the thread ... not the tip or root but the body. As long as the nut is softer then the bolt you should be good to go. Again, this is a one shot deal for the nut, but the bolt should be good for a couple of uses.

[KeWLKaT]

Wow, those are some nice tips right there. I guess you have nothing to lose by trying those! :)

[tharptroy]

another thing you could do if you're desperate is use a nut/bolt with a slightly different thread pitch or diameter.

for example, use the closest sized standard nut instead of a metric

[Elantra2.001]

The difference between a standard and a metric lock nut of similar sizes is so small that you should be fine. It's like the "crush" washer that you are supposed to use for the oil pan, replace it everytime it's removed. I didn't have a problem with any studs, bolts or nuts backing out on my car, but it never ran right anyway.

[Keyan]

For my setup I am just using normal bolts and locking washers and I crank down on them ****ing tight.

[only1db]

after heating and cooling...they WILL come out....

like mentioned the simple solution are the brass nuts.

[KeWLKaT]

after heating and cooling...they WILL come out....

I don't know man... I NEVER had a problem with my heatshield bolts. NEVER.

[only1db]

but they are of the same material arent they? and not to mention with the turbo it gets twice as hot....

[Denisst99]

copper coated jam nut and good studs are the way to go
then do get a bit expensive, but once they're on the stay on ;)