Are studs better than bolts for exhaust manifold?
Studs provide the ability to obtain much more accurate torque values because the studs don’t twist during tightening as do bolts. Because the studs remain stationary during nut tightening, the studs stretch in one axis alone, providing much more even and accurate clamping forces.
What size are Cummins manifold bolts?
Thread Size: M10 (10.0 mm.)
Can you reuse exhaust manifold studs?
You could reuse them, if you think they look good, but your chances of one breaking later have gone up now. I replace them every time, just heat the area around the studs, and melt a candle or crayon into the threads, let cool, they should come out easy, may need to heat again.
Do you put anything on exhaust manifold bolts?
If you are reusing exhaust manifold bolts (which we don’t recommend), apply a metal fortified anti-seize to your manifold bolts. If you’ve just removed the broken bolts and ready to complete the repair, chase the threads clean and use fresh OEM bolts for best results.
Do studs need to bottom out?
Bottoming or shouldering of studs should be avoided by driving them only to a predetermined depth. Bottoming or shouldering causes uneven stand-out and sets up undesirable radial compressive stresses which often become relieved during service operation, permitting the stud to loosen.
What is the advantage of head studs?
The use of head studs will aid in cylinder head installation, simply from a standpoint of gasket and head alignment. This is especially helpful in an application where frequent head removal will occur. In terms of function, the use of studs provides much more accurate and consistent torque loading.
Why do exhaust manifold bolts have spacers?
Spacers help to stop manifold bolts breaking due to the expansion and contraction due to heat. By fitting spacers and long bolts they have more room to grow without breaking.
Why do exhaust bolts break?
That rapid heat causes the exhaust manifold material to expand, which puts a tremendous strain on the bolts and/or studs holding the manifolds to the cylinder heads. After hundreds of expansion and contraction cycles, the studs or bolts finally fail.
How do you install exhaust manifold studs?
Easiest way to install the studs, is double-nuts on the fine thread end. Simply tighten one nut against the other, and use the top nut to run the stud in. Sealant… paint the threads going into the head…and the end of the stud.
Should you use Loctite on exhaust manifold bolts?
I have always used loctite nickel antisieze on the exhaust manifold socket head bolts together with a lock washer. Never had a probelm with them coming loose. However I check the bolt tightness after the first few weeks of use as the gaskets can compress over time with heat cycles. You could use a loctite.
Should I put anti seize on header bolts?
Anti seize is a good idea on header bolts in general, in my experience. Even steel in steel they tend to freeze up over time (if they don’t fall out, as they did to you). The advice to use some type of lock is also a good one.
Is a stud stronger than a bolt?
Main studs Studs provide the ability to obtain much more accurate torque values because the studs don’t twist during tightening as do bolts. Because the studs remain stationary during nut tightening, the studs stretch in one axis alone, providing much more even and accurate clamping forces.