Jump to content


Welcome to Ultimate Subaru Message Board, my lurker friend!

Welcome to Ultimate Subaru Message Board, an unparalleled Subaru community full of the greatest Subaru gurus and modders on the planet! We offer technical information and discussion about all things Subaru, the best and most popular all wheel drive vehicles ever created.

We offer all this information for free to everyone, even lurkers like you! All we ask in return is that you sign up and give back some of what you get out - without our awesome registered users none of this would be possible! Plus, you get way more great stuff as a member! Lurk to lose, participate to WIN*!
  • Say hello and join the conversation
  • Subscribe to topics and forums to get automatic updates
  • Get your own profile and make new friends
  • Classifieds with all sorts of Subaru goodies
  • Photo hosting in our gallery
  • Meet other cool people with cool cars
Seriously, what are you waiting for? Make your life more fulfilling and join today! You and your Subaru won't regret it, we guarantee** it.

* The joy of participation and being generally awesome constitutes winning
** Not an actual guarantee, but seriously, you probably won't regret it!

Serving the Subaru Community since May 18th, 1998!

Guest Message by DevFuse
 

Photo
- - - - -

exhaust studs vs bolts


  • Please log in to reply
15 replies to this topic

#1 baccaruda

baccaruda

    YOUR FAVORITE MOD

  • Moderator
  • 6,942 posts
  • SpoVegas, WA

Posted 30 August 2003 - 08:00 PM

the engine i put in skeet's wagon is missing 3 exhaust studs. is there any reason i couldn't use bolts instead?

#2 archemitis

archemitis

    guy smiley

  • Members
  • 3,554 posts
  • the big minnie

Posted 30 August 2003 - 08:20 PM

the only bad thing about that is you are more apt to pull the threads out of the head. i'de try and get some more studs. but then again i have about 4 bolts and 4 studs between my two subarus.

#3 canajun2eh

canajun2eh

    USMB is life!

  • Members
  • 222 posts
  • Ottawa, ON, Canada

Posted 30 August 2003 - 08:35 PM

Don't use bolts. You can't tighten them properly without stripping the threads in the head. (I speak from experience.)

Studs and new stainless steel nuts aren't all that expensive, and are readily available from your dealer. It's false economy to use anything else.

Be sure to apply anti-seize compound to the studs before installing the nuts. Apply more to cover the nuts after installation and tightening.

#4 baccaruda

baccaruda

    YOUR FAVORITE MOD

  • Moderator
  • 6,942 posts
  • SpoVegas, WA

Posted 30 August 2003 - 09:28 PM

so much for laziness. thanx

#5 TomRhere

TomRhere

    Certified BRAT nut!!!

  • Members
  • 3,967 posts
  • Hillsdale, Mi. USA

Posted 31 August 2003 - 08:55 AM

When I tore down my engine in the '82 for a reseal, I found the exhaust mounting threads in the heads were striped out, 3 of them anyways. Posted question on here about repair of these. Got answers of using Heli-coils, re-dil and tap to larger size, and one of using a 7/16" bolt in place of the stock ones. I took the idea of the 7/16" bolt, and went a bit further. I used a starter tap first, then followed with a bottoming tap, for those few extra turns of thread. The tap size used is 7/16"-14, this is a coarse thread, which in my belief is better in aluminum than fine thread. I used a 1'' long bolt with lock washer to mount the exhaust pipe flange to the heads. The bolt is a SHCS, or in other words, you need an Allen wrench to turn it. The 7/16" tap will screw right into the holes in the head with no need to pre-drill. I may at a later time use studs in place of the bolts, but either will work. And actually, both a stud or a bolt will break of if they sieze in the hole. Use of Anti-sieze is highly recommended on all bolts/studs on these, or any vehicle. Just my .02.....................

#6 MorganM

MorganM

    Do you Subaru?

  • Members
  • 8,390 posts
  • TwinCities

Posted 31 August 2003 - 12:40 PM

Ive ran bolts for quite some time. They are a good temporary solution. Latly I've been needing to remove/install the headers so much that they never get too loose.

Studs is the proper solution but bolts will get you by.

It was a little embarasing on base a year ago when two of the bolts DID come off a header... WOW did it get LOUD :D and the sparks from my exhuast draging for a few yards was a siight I'm sure :eek:

Maybe some lock washers would hold them in but then you run into the problem archemitis points out... cant torque them down tight enugh in those aluminum heads

#7 Partsman

Partsman

    Eat, Live, Breath Subaru

  • Members
  • 262 posts
  • sunny Eugene, OR

Posted 27 January 2004 - 10:49 PM

Man, I just wanted to give credit for a great and easy fix! I used 7/16-14 plug tap, then bottoming tap; put in 7/16x1 1/2" studs and a new gasket, put on a washer to take up a little extra space where the stud thread didn't go to the end, and used brass manifold nuts and Loctite. Didn't even have to drop the Y-pipe - I used the holes in the pipe to align the taps!

EXCELLENT! :headbang: :headbang: !

but now I have to carry one american size tool!

#8 subiemech85

subiemech85

    SIX STAR SERVICE

  • Members
  • 2,710 posts
  • down by the river

Posted 07 September 2004 - 12:44 PM

use double nuts

#9 Snowman

Snowman

    Midnight Passenger

  • Members
  • 3,538 posts
  • Haines

Posted 07 September 2004 - 08:59 PM

I've had to deal with a bunch of these recently while working on other peoples' soobs, and since it takes upwards of a week to get the proper studs where I live, I've come up with my own solution:

Make your own studs!
Just get a bolt that's the same diameter and thread pitch, and at least as long as the stock stud. Cut the head off of the bolt, round that end off a tad with a file, and run a die (if you've got one) up and down the bolt a couple of times to clean it up. Presto! new exhaust stud!

If the hole is stripped, I've had great luck with running a tap in and out once or twice, then using a thread renewal product made by Loctite that I can't remember the name of. It's a two-part metal epoxy a lot like JB Weld, with a third part that you coat the threads with. They claim it makes holes good as new for use with up to grade 5 US bolts, which is plenty for use in exhaust stud holes.

#10 harpua

harpua

    Subaru Fanatic!

  • Members
  • 442 posts
  • nowhere, USA

Posted 08 September 2004 - 06:34 PM

SUCCESS!!! This has been the best peice of message board knowledge that i have come accross to date.

I went and picked up the 7/16-14 tap, new studs and nuts...lock washers, and locktite, installed it all, and now my turbo works again. I noticed that i was able to torque everything down much tighter, so hopefully it will hold this time.

I was starting to get frustrated after the 5th time in 4 months having to put in new gaskets....

run studs not bolts....simple as that.

#11 RonVee

RonVee

    USMB Regular

  • Members
  • PipPipPip
  • 35 posts
  • Ellenboro, NC

Posted 08 August 2006 - 03:13 AM

Just wanted to say thanks for the Great Exhaust Stud Fix! Tryed all the other stuff...problem always came back.

Did the 7/16"-14 tap with new 7/16" studs. Works great. They are in there now for sure!

Big Thanks to TomRhere!!! This fix is fantastic!


Peace.....Ron

PS: I did a search before I posted this and alot of threads had Tom's name as the source of the fix so I hope I am correct.

Real Big Thanks goes to this forum and it's members for helping me through the years keep my Subies goin!!!!!!

#12 exister99

exister99

    USMB is life!

  • Members
  • 149 posts
  • Austin, Texas

Posted 19 September 2006 - 09:47 AM

There seems to be some difference of opinion on this board regarding what exactly to apply to the threads of the exhaust studs prior to installation. One poster said anti-seize and another locktite.

After a recent offroading trip my exhaust got a lot louder. Upon inspection I discovered that I had lost one of the studs entirely and the other 3 were loose. This would lead me to believe it would be best to apply locktite to these high vibration fasteners to keep from losing my Y-pipe entirely. Any thoughts?

Also, I plan on ordering a new stud from McMaster.com. Does anyone know of another source?

#13 DasWaff

DasWaff

    USMB Regular

  • Members
  • PipPipPip
  • 83 posts
  • Durham

Posted 19 September 2006 - 09:57 AM

Just wanted to say thanks for the Great Exhaust Stud Fix! Tryed all the other stuff...problem always came back.

Did the 7/16"-14 tap with new 7/16" studs. Works great. They are in there now for sure!


Agreed, this was the only fix that worked on my old GL, and it worked well. My only addition would be take your time when you retap. DW

#14 Spockva

Spockva

    New User

  • Members
  • PipPip
  • 29 posts
  • Fredericksburg

Posted 24 September 2006 - 08:31 PM

I've had to deal with a bunch of these recently while working on other peoples' soobs, and since it takes upwards of a week to get the proper studs where I live, I've come up with my own solution:

Make your own studs!
Just get a bolt that's the same diameter and thread pitch, and at least as long as the stock stud. Cut the head off of the bolt, round that end off a tad with a file, and run a die (if you've got one) up and down the bolt a couple of times to clean it up. Presto! new exhaust stud!

If the hole is stripped, I've had great luck with running a tap in and out once or twice, then using a thread renewal product made by Loctite that I can't remember the name of. It's a two-part metal epoxy a lot like JB Weld, with a third part that you coat the threads with. They claim it makes holes good as new for use with up to grade 5 US bolts, which is plenty for use in exhaust stud holes.


I also used the thread renewal epoxy with great results. In the holes that were badly stripped, I found that the next larger metric bolt size was easy to enlarge to, and the studs also fit through the holes in the flanges. Very easy to do and kept it metric too.

#15 baccaruda

baccaruda

    YOUR FAVORITE MOD

  • Moderator
  • 6,942 posts
  • SpoVegas, WA

Posted 24 September 2006 - 09:24 PM

anti-seize is for things that you wish to remove again sometime, threadlocker is for things that you want to stay there :P
use threadlocker when installing the studs and use anti-seize, if you wish, on the nuts after the exhaust pipe is mounted. I don't know that it's really necessary if you take your car apart as often as most of us do... don't forget the lockwashers...

#16 daeron

daeron

    Cunning Linguist

  • Members
  • 3,600 posts
  • West Palm Beach

Posted 25 September 2006 - 01:55 AM

Nev-R-Seez +++

its more important than loctite in my book.

of course, my book wasn't written with an aluminum block... but i dont care. nevrseez is the bestest stuff to have in a shop, evAr!!!!! lugnuts, exhaust and intake bolts, suspension bolts, ANYTHING that EVER could possibly get wet or rusted or tightly bound needs to be brushed with nevrseez... torque and lockwashers can usually keep anything tight, and anything that REALLY needs positive locking gets a castle nut and a pin anyhow, right?

okay, so loctite is important too.. but nevrseez is more overlooked.




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users