DP bolts keep backing off.
#1
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im using essentially a RB dp and the exhaust bolts that hold the thing to the turbo keep backing off.
they are the factory bolts for the exhaust. why the hell do that keep doing it. i mean in 1500 miles the are almost about to fall off.
can i use a locking washer or is that going to like...melt?
they are the factory bolts for the exhaust. why the hell do that keep doing it. i mean in 1500 miles the are almost about to fall off.
can i use a locking washer or is that going to like...melt?
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#5
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there is a place called Fastenall where i live. im probably going to go there to day and ask them what i can use that they sell. maybe NAPA might have something.
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Engine, Not Motor
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I'm almost 100% certain that the turbo to downpipe nuts are M10. The reason I know is because I used the exact same copper locknuts on the manifold to turbo flange as I did the downpipe flange. That said, a local fastener shop probably has similar nuts as well.
#9
XBL** Ownicus
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Do you really need copper lock washers? I used regular stainless grade 8 hardware I picked up at the local H/w store and had that crap on there for ~ a year and it never loosened up. It came off pretty nicely too when I put all my Racing Biatch stuff on.
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Years ago, when I lived in the boonies, we had to make do with whatever we had.
We made a lock nut by carefully crushing a nut in a vise to make the thread hole slightly oval.
It's not recommended for aircraft, but it does the job for cars.
We made a lock nut by carefully crushing a nut in a vise to make the thread hole slightly oval.
It's not recommended for aircraft, but it does the job for cars.
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Originally Posted by SureShot
Years ago, when I lived in the boonies, we had to make do with whatever we had.
We made a lock nut by carefully crushing a nut in a vise to make the thread hole slightly oval.
It's not recommended for aircraft, but it does the job for cars.
We made a lock nut by carefully crushing a nut in a vise to make the thread hole slightly oval.
It's not recommended for aircraft, but it does the job for cars.
#16
Just double nut the studs (ie jam nuts).
When i switched to a copper gasket and stainless nuts on the turbo to downpipe connection I had this problem of the nuts getting loose very quickly because of the high rate of thermal expansion in both materials and the resultant expansion/contraction cycles that loosen the nuts.
2 stainless nuts solved the problem very nicely!
When i switched to a copper gasket and stainless nuts on the turbo to downpipe connection I had this problem of the nuts getting loose very quickly because of the high rate of thermal expansion in both materials and the resultant expansion/contraction cycles that loosen the nuts.
2 stainless nuts solved the problem very nicely!
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use treadlock. it works really good and can get them off easy later when you have to. Just use a lito more force on breaking the bolt when you have to take it off. You can get it at any hardware store. Its call treadlock!
#19
No, on the turbo manifold to turbo and turbo to downpipe threads the thread lock burns off, but the carbon it leaves in the threads will help keep the nuts on a bit.
I used thread lock before I went to jam nuts. Thread lock worked fine on stock gasket and flanges but not on my stainless turbo backplate, copper gasket, stainless downpipe flange and stainless nuts- that was far too much expansion/contraction.
I used thread lock before I went to jam nuts. Thread lock worked fine on stock gasket and flanges but not on my stainless turbo backplate, copper gasket, stainless downpipe flange and stainless nuts- that was far too much expansion/contraction.
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Originally Posted by Low Impedance
also, ifs they are the factory nuts what is making them fall off so quick? ![Suspect](https://www.rx7club.com/images/smilies/suspect.gif)
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The factory nuts are a "one time use" locking nut
You are supposed to replace them every time you take them off.
They are a "Pinch" design, and once used, they won't lock up again unless you use the aforemetnioned lock washers
#22
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Originally Posted by YearsOfDecay
The factory nuts are a "one time use" locking nut
You are supposed to replace them every time you take them off.
They are a "Pinch" design, and once used, they won't lock up again unless you use the aforemetnioned lock washers
You are supposed to replace them every time you take them off.
They are a "Pinch" design, and once used, they won't lock up again unless you use the aforemetnioned lock washers
Mazda used a thin sheet of metal, welded to the downpipe, each with two thin tabs that were bent against two of the sides of the nut to hold the nuts in position. To loosen the nuts, you had to bend these tabs with a screwdriver before the socket would fit on.
The actual nuts are not one time use. They are just regular nuts and can be reused.
The FSM clearly does not show "replace" when the exhaust is removed, like it does for other lock washers. Notice how the FSM clearly states replace on all intended hardware?
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