Exhaust stud flange nut size? Anyone?
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Cruiser
Joined: May 2010
Posts: 139
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From: Ann Arbor, MI
Exhaust stud flange nut size? Anyone?
Re-installing exhaust after having the Y-pipe TIG welded. Having a bitch of a time torquing down the lower flange nut. Anyone know what size (thread pitch and count) in case I round it off and need to replace? Loaned my thread gauge and never saw it again. I guess I could just take it to HD, but was hoping someone here knew what was right. I'm thinking of using a hex nut and washer instead.
Also, I'm using a few combinations to try to get at it (deep-well socket, different length extensions). Have the O2 sensor out so it doesn't block me. What tool do you guys use??? Such a PITA!
I'm also having an issue getting the bracket clamp flush. I've backed it out and re-seated it a few times. Not being able to gain purchase on the lower flange is keeping me from installing it flush.
Thanks, ya'll!
BTW, dealer wanted $460 for new Y-pipe and install. So far I'm in for $40 and just have to button this up right.
Also, I'm using a few combinations to try to get at it (deep-well socket, different length extensions). Have the O2 sensor out so it doesn't block me. What tool do you guys use??? Such a PITA!
I'm also having an issue getting the bracket clamp flush. I've backed it out and re-seated it a few times. Not being able to gain purchase on the lower flange is keeping me from installing it flush.
Thanks, ya'll!
BTW, dealer wanted $460 for new Y-pipe and install. So far I'm in for $40 and just have to button this up right.
Extreme HDF Member
Joined: Sep 2010
Posts: 14,744
Likes: 402
From: Phoenix '53, '88, '09 Big Twins
here's specs from the 09 manual, not as tight as you would think:
Tighten the exhaust system as follows:
a. Tighten the top nut of the front cylinder head exhaust
flange to 9-18 in-lbs (1-2 Nm). Tighten the bottom
nut to 100-120 in-lbs (11.3-13.6 Nm). Final tighten
the top nut to 100-120 in-lbs (11.3-13.6 Nm).
b. Tighten the bottom nut of the rear cylinder head
exhaust flange to 9-18 in-lbs (1-2 Nm). Tighten the
top nut to 100-120 in-lbs (11.3-13.6 Nm). Final tighten
the bottom nut to 100-120 in-lbs (11.3-13.6 Nm).
I gotta couple of wrench combos i use- depending on the bike, I have crowfoots
a 1/4" drive 1/2" works well for some of the nuts
Mike
Tighten the exhaust system as follows:
a. Tighten the top nut of the front cylinder head exhaust
flange to 9-18 in-lbs (1-2 Nm). Tighten the bottom
nut to 100-120 in-lbs (11.3-13.6 Nm). Final tighten
the top nut to 100-120 in-lbs (11.3-13.6 Nm).
b. Tighten the bottom nut of the rear cylinder head
exhaust flange to 9-18 in-lbs (1-2 Nm). Tighten the
top nut to 100-120 in-lbs (11.3-13.6 Nm). Final tighten
the bottom nut to 100-120 in-lbs (11.3-13.6 Nm).
I gotta couple of wrench combos i use- depending on the bike, I have crowfoots
a 1/4" drive 1/2" works well for some of the nuts
Mike
Last edited by mkguitar; May 15, 2012 at 10:27 PM.
The nut is 1/2", stud is 5/16x20 threads per inch. Standard 5/16 , they do make over size studs for inserting into helicoils into the heads, but if you have never been there it should be standard corse thread. Don't try to use a hardware store nut, heat will cook it in a few runs. Need actual exhaust rated fasteners. They are made of a bi-metal compound that resists heat issues. (hot cold cycles all the time)
Elite HDF Member
Joined: Sep 2007
Posts: 4,928
Likes: 69
From: Near Myrtle Beach, SC
Sounds like you need a manual, a good inch pound torque wrench, wobble extensions, and then you will have the tools you need to do the job properly. Torque to specs, take a few rides, then re-check the torque. Never over torque these nuts.
Seasoned HDF Member
Joined: Jan 2008
Posts: 5,914
Likes: 3,205
From: On one of 10,000
here's specs from the 09 manual, not as tight as you would think:
Tighten the exhaust system as follows:
a. Tighten the top nut of the front cylinder head exhaust
flange to 9-18 in-lbs (1-2 Nm). Tighten the bottom
nut to 100-120 in-lbs (11.3-13.6 Nm). Final tighten
the top nut to 100-120 in-lbs (11.3-13.6 Nm).
b. Tighten the bottom nut of the rear cylinder head
exhaust flange to 9-18 in-lbs (1-2 Nm). Tighten the
top nut to 100-120 in-lbs (11.3-13.6 Nm). Final tighten
the bottom nut to 100-120 in-lbs (11.3-13.6 Nm).
I gotta couple of wrench combos i use- depending on the bike, I have crowfoots
a 1/4" drive 1/2" works well for some of the nuts
Mike
Tighten the exhaust system as follows:
a. Tighten the top nut of the front cylinder head exhaust
flange to 9-18 in-lbs (1-2 Nm). Tighten the bottom
nut to 100-120 in-lbs (11.3-13.6 Nm). Final tighten
the top nut to 100-120 in-lbs (11.3-13.6 Nm).
b. Tighten the bottom nut of the rear cylinder head
exhaust flange to 9-18 in-lbs (1-2 Nm). Tighten the
top nut to 100-120 in-lbs (11.3-13.6 Nm). Final tighten
the bottom nut to 100-120 in-lbs (11.3-13.6 Nm).
I gotta couple of wrench combos i use- depending on the bike, I have crowfoots
a 1/4" drive 1/2" works well for some of the nuts
Mike
The nut is 1/2", stud is 5/16x20 threads per inch. Standard 5/16 , they do make over size studs for inserting into helicoils into the heads, but if you have never been there it should be standard corse thread. Don't try to use a hardware store nut, heat will cook it in a few runs. Need actual exhaust rated fasteners. They are made of a bi-metal compound that resists heat issues. (hot cold cycles all the time)
Thanx for the help!
No damage done riding it on 2 tanks home I'm guessing.
I'm thinking about replacing that nut with a nylock nut,is that too much heat there for a nylon insert nut? "Locktite is your friend"
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