Lycoming exhaust studs

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swampsquatch09
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Lycoming exhaust studs

Post by swampsquatch09 » Wed Jul 16, 2014 6:57 pm

Had 2 bugger up on me has anyone ever used regular bolts and lock washer in place of exhaust studs, I'm thinkin drilling a hole to safety wire in the bolt head any thoughts?
14ft Maxcraft, 70" WW Signature Series 320 lycoming
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diamondback0320
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Re: Lycoming exhaust studs

Post by diamondback0320 » Wed Jul 16, 2014 10:20 pm

Ive used a bolt in a pinch but ended up drillin out tapp the hole & helicoil

twister69z
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Re: Lycoming exhaust studs

Post by twister69z » Wed Jul 16, 2014 11:41 pm

Please only in emergency situations use a bolt . If you can install a helicoil and install the correct part number stud. 31-c12 is for 2 bolt exhaust. Use quality hardware ( nuts and lock washers) make sure flanges are flat and gasket seals gasses from the studs.
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terrible ted
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Re: Lycoming exhaust studs

Post by terrible ted » Thu Jul 17, 2014 7:56 am

Do you mean the stud threads or the head threads. I had studs look like there trashed but run a die over them and there good to go some time the brass just mushes into the thread. yes use brass nuts

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mojoe
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Re: Lycoming exhaust studs

Post by mojoe » Thu Jul 17, 2014 12:08 pm

twister69z wrote:If you can install a helicoil and install the correct part number stud. 31-c12 is for 2 bolt exhaust. Use quality hardware ( nuts and lock washers) make sure flanges are flat and gasket seals gasses from the studs.
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How tight should the bolts be torqued?
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swampsquatch09
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Re: Lycoming exhaust studs

Post by swampsquatch09 » Thu Jul 17, 2014 3:51 pm

The bolt threads are mashed, the nut is froze on tryed to get it off tryed heat, penatrant, jam nut, nothin worked I'm staying away from cad plated from now on,

I put different headers on for flex pipe the ones I had where to close to the cage, got some stainless studs on order thanks fellas,

Does it matter what side of the stud goes into the cyl head? I noticed there's a long side and a short side I'm guessing short in head and long side for headers?
14ft Maxcraft, 70" WW Signature Series 320 lycoming
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Re: Lycoming exhaust studs

Post by dusty burch » Thu Jul 17, 2014 8:56 pm

Antisieze and stainless hardware is the only way to go....... it is not if but when you take it apart it is a hell of alot easier iI have used 1 1/2 x5/16 set screw instead of a stud and have had good luck

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Re: Lycoming exhaust studs

Post by dusty burch » Thu Jul 17, 2014 8:57 pm

Antisieze and stainless hardware is the only way to go....... it is not if but when you take it apart it is a hell of alot easier iI have used 1 1/2 x5/16 set screw instead of a stud and have had good luck

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Re: Lycoming exhaust studs

Post by jeepinocala1111 » Fri Jul 18, 2014 6:43 am

I have some expeirence with this one :) Kroil get some it is the absolute best penetrating chemical just dont get it on yourself very toxic and heat those pencil torches are great you will get them out with this process. Useing a bolt is fine if youve already done a helicoil just make sure it is a grade8 or better and has a good lock washer.

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Re: Lycoming exhaust studs

Post by terrible ted » Fri Jul 18, 2014 8:33 am

if you can take a small drill and drill the straight along with the stud thru the nut edge. ie dremil the edg of the nut.

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Re: Lycoming exhaust studs

Post by Gary S » Sat Jul 19, 2014 6:55 am

Use a stud. When you tighten a nut on a stud, your putting only a straight pull on all the threads in the cylinder. When you tighten a bolt you are not using all the threads in the cylinder.

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Re: Lycoming exhaust studs

Post by terrible ted » Sat Jul 19, 2014 8:08 am

dusty burch wrote:Antisieze and stainless hardware is the only way to go....... it is not if but when you take it apart it is a hell of alot easier iI have used 1 1/2 x5/16 set screw instead of a stud and have had good luck

If you use the brass nut the nut will always come. May leave the stud thread full of brass. that easy to clean with a die.

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