Results 1 to 18 of 18

Thread: wobbly exhaust manifold studs

Discussions of Triumph motor cars

  1. #1
    Senior Member
    Join Date
    Aug 2016
    Location
    Burlington NC
    Posts
    104
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    0
    Thanked in
    0 Posts

    wobbly exhaust manifold studs

    I had to replace all 3 stud bolts on the exhaust manifold, the threads were not salvageable. Well of course over time the studs had pretty much welded themselves in and after trying many options, the only one left to was to drill them out. Managed to get as close to center of each that I could and after almost a day of step drilling, finally had daylight all the way through. I had gotten new studs from moss which are 3/8 unc (16 thread count) so cleaned the hole with a 5/16 bit to re-tap. It was one of those ahaa moments when you think ok, finally getting somewhere BUT apparently the holes are a teeny tiny bit out of round and two of the studs are a bit wobbly and I'm not convinced they are getting a strong enough bite.
    What I would really like to do is fill the holes by welding and then redrill but I read where welding cast iron is tricky business.
    Sorry for the long explanation to get to my question but since there are some threads that may create a good bite for jb weld what do ya think about smearing someof that in the holes then redrill? Wouldn't take much of it but do ya think the cycles of extreme heat and cool down would create problems?

  2. #2
    Luke Skywalker trrdster2000's Avatar
    Join Date
    Sep 2004
    Location
    Salisbury NC
    Posts
    1,820
    Thanks Thanks Given 
    12
    Thanks Thanks Received 
    9
    Thanked in
    9 Posts

    Re: wobbly exhaust manifold studs

    Dash, I have used a longer stud and topped it with a nut on the top side. You might have to cut the nut in half in one place, just thread it on through and into the nut. That will hold it with the big brass nut on the bottom. If you heat it too red, brazing would work.

    Wayne
    '37 MG TA, '49 Triumph Roadster, '70 TR6, 2000 Jaguar XK8, '78 Spit6

  3. #3
    Great Pumpkin TR3driver's Avatar
    Join Date
    Aug 2003
    Location
    Sunny So California
    Posts
    19,552
    Thanks Thanks Given 
    8
    Thanks Thanks Received 
    138
    Thanked in
    129 Posts

    Re: wobbly exhaust manifold studs

    Sorry, JB Weld hasn't a prayer. Can't take the heat, and isn't strong enough even without the heat.
    My suggestion would be a Helicoil or similar.
    https://www.amazon.com/Helicoil-5521...3%2F8+helicoil
    Randall
    56 TR3 TS13571L once and future daily driver
    71 Stag LE1473L waiting engine rebuild
    71-72-73 Stag LE2013LBW waiting OD gearbox rebuild

  4. #4
    Senior Member
    Join Date
    Apr 2015
    Location
    Baltimore, MD
    Posts
    102
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    1
    Thanked in
    1 Post

    Re: wobbly exhaust manifold studs

    Hi,

    I installed two Helicoil's in the exhaust side of my cylinder head (TR-4a). If you drill it out and nick the water passage, put a little thread sealant on the fastener. BTW, a LH drill bit works great for removing broken studs.


    RG

  5. #5
    Yoda CJD's Avatar
    Join Date
    Feb 2011
    Location
    Arlington, TX, USA
    Posts
    5,536
    Thanks Thanks Given 
    6
    Thanks Thanks Received 
    46
    Thanked in
    45 Posts

    Re: wobbly exhaust manifold studs

    The book solution is to heli-coil the bad holes.

    Welding old cast exhaust manifolds will absolutely NOT work. The cycles of heating above the transition temp while the manifold is in use changes the metal composition. The free carbon turns to graphite and is no longer weldable. If you can get the weld to stick, it will be rock hard when trying to cut new threads.

    Before you devote too much time, realize you can find used manifolds readily and cheaply. Personally, I'd invest in a heli-coil kit, and if that goes south just replace the manifold.
    John

    1955 TR2

  6. #6
    Yoda Marvin Gruber's Avatar
    Join Date
    Jan 2003
    Location
    Florence, Al
    Posts
    3,046
    Thanks Thanks Given 
    1
    Thanks Thanks Received 
    4
    Thanked in
    4 Posts

    Re: wobbly exhaust manifold studs

    Why not just drill it out a little and use new bolt and nut. May not be pretty but will work.
    Marv

  7. #7
    Senior Member
    Join Date
    Aug 2016
    Location
    Burlington NC
    Posts
    104
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    0
    Thanked in
    0 Posts

    Re: wobbly exhaust manifold studs

    Thanks to all for the advice... a more careful inspection revealed there is still a little of the old stud remnants still in at least one of the holes even after all that drilling and re-taping so I should just go ahead and use the longer bolt w/nut option but I'm sometimes a stubborn hard head when when it comes to keeping some things as close to original as possible even if no one but me would ever know the difference and this is a prime example. It's a stupid self inflicted aggravating curse for sure! Anyway, I'm hoping using the 25/64 bit for the helicoil with clean it up and leave enough bite for the insert. If not, well then bolt w/nut it will be. I eventually may wanna install headers but its a new overhaul that's back on the chassis (body still off) and, for now, my primary mission is to get everything outside the block reassembled using as many original parts as possible. The goal being to at least start it to check for potential issues before I get carried away investing in parts I can do without if that makes any sense.

  8. #8
    Luke Skywalker trrdster2000's Avatar
    Join Date
    Sep 2004
    Location
    Salisbury NC
    Posts
    1,820
    Thanks Thanks Given 
    12
    Thanks Thanks Received 
    9
    Thanked in
    9 Posts

    Re: wobbly exhaust manifold studs

    Dash, I will look in he warehouse were I have a few TR parts and if what you need is there, I'll donate it to your OCD. LOL You will have to come get it.
    I'll let you know tomorrow.
    Wayne
    '37 MG TA, '49 Triumph Roadster, '70 TR6, 2000 Jaguar XK8, '78 Spit6

  9. #9
    Jedi Knight
    Join Date
    Apr 2013
    Location
    redding,ca
    Posts
    1,067
    Thanks Thanks Given 
    1
    Thanks Thanks Received 
    11
    Thanked in
    11 Posts

    Re: wobbly exhaust manifold studs

    I read this with interest as I have an exhaust manifold sitting in the shop needing the three studs to be replaced. I like the idea of using a bolt and nut---but what about welding a glob on the end of the bolt in place of the nut? I am thinking that there is little room for the nut without cutting out room for it.
    Charley

  10. #10
    Jedi Warrior
    Join Date
    Jun 2010
    Location
    Hudson, OH
    Posts
    583
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    1
    Thanked in
    1 Post

    Re: wobbly exhaust manifold studs

    If it's a 4A manifold they are getting hard to find and expensive when you do find one. The Heli-coil sounds like a good solution.

  11. #11
    Luke Skywalker
    Join Date
    Aug 2010
    Location
    Strafford, NH
    Posts
    1,759
    Thanks Thanks Given 
    9
    Thanks Thanks Received 
    17
    Thanked in
    17 Posts

    Re: wobbly exhaust manifold studs

    Ditto on the Helicoils, they are relatively inexpensive, easy and last a long time, perhaps longer than the original threads. Tom
    1960 TR3A TS73117 (under endless restoration, owned since 1964)
    1959 TR3A TS58023 (in case I never finish the one above)
    1969 Triumph Herald 13/60 (a whim)
    1970 Lotus Elan Plus 2 /0023/N
    1992 BMW325IC (fun to drive)

  12. #12
    Luke Skywalker trrdster2000's Avatar
    Join Date
    Sep 2004
    Location
    Salisbury NC
    Posts
    1,820
    Thanks Thanks Given 
    12
    Thanks Thanks Received 
    9
    Thanked in
    9 Posts

    Re: wobbly exhaust manifold studs

    Dash, Sorry to say no TR4 exhaust but I did find the dimmer switch I needed for the Spit6 I'm building. So not a total lost trip.
    There were a lot of small chrome bits, if you need any of those type things.

    Wayne
    '37 MG TA, '49 Triumph Roadster, '70 TR6, 2000 Jaguar XK8, '78 Spit6

  13. #13
    Senior Member
    Join Date
    Aug 2016
    Location
    Burlington NC
    Posts
    104
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    0
    Thanked in
    0 Posts

    Re: wobbly exhaust manifold studs

    Thanks Wayne for checking..seems like every inch of this project wants to fight me tooth and nail so haven't gotten to the glitter pieces yet. I will check back with ya though when I manage to get that far. However I am dissapointed you didn't find a decent tr4 body when you were rumaging in your warehouse though..lol
    BTW, the manifold is gonna turn out ok..helicoil working out fine..the block side was a little rough so took it to the machine shop to have it skimmed
    Dave

  14. #14
    Luke Skywalker trrdster2000's Avatar
    Join Date
    Sep 2004
    Location
    Salisbury NC
    Posts
    1,820
    Thanks Thanks Given 
    12
    Thanks Thanks Received 
    9
    Thanked in
    9 Posts

    Re: wobbly exhaust manifold studs

    Dave, Had a bunch of body parts a few years back, TR4A and 6, but a crack head wiped out all of it, along with all the scaffolding used in construction.
    He might have got $3 for the fenders and hoods each.
    Still have a couple of transmissions. Have a guy coming from Florida for interior parts next month, his is real bad.
    Let me know if I can help.

    Wayne
    '37 MG TA, '49 Triumph Roadster, '70 TR6, 2000 Jaguar XK8, '78 Spit6

  15. #15
    Senior Member
    Join Date
    Aug 2016
    Location
    Burlington NC
    Posts
    104
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    0
    Thanked in
    0 Posts

    Re: wobbly exhaust manifold studs

    Wayne, a long way to go before I'm ready for it but I know I'll need a heater housing eventually..I have a good core and fan etc.
    Oh , had a roofer here a couple weeks ago and the guy recognized the tr4 right off the bat. As luck would have it, he said his father had a tr4a and it has been in his warehouse for 30+ years. Well goes without saying I started paying attention! He said the engine was blown but the rest was in good shape. Not sure of his definition of "good shape" but aparrently it's buried in there and hard to get to at the moment but he said he would call so I could come look at it. If it really is in decent shape and I can talk him out of it, I may be switching projects. May as well lock me in a rubber room now and throw away the key, I've obviously lost my mind!!


    Dave

  16. #16
    Luke Skywalker trrdster2000's Avatar
    Join Date
    Sep 2004
    Location
    Salisbury NC
    Posts
    1,820
    Thanks Thanks Given 
    12
    Thanks Thanks Received 
    9
    Thanked in
    9 Posts

    Re: wobbly exhaust manifold studs

    Best of British lucky laddie.You must not be married or like me, have a wife that wants them all. Oh. you can fix that, she says.

    Wayne
    '37 MG TA, '49 Triumph Roadster, '70 TR6, 2000 Jaguar XK8, '78 Spit6

  17. #17
    Luke Skywalker trrdster2000's Avatar
    Join Date
    Sep 2004
    Location
    Salisbury NC
    Posts
    1,820
    Thanks Thanks Given 
    12
    Thanks Thanks Received 
    9
    Thanked in
    9 Posts

    Re: wobbly exhaust manifold studs

    Dave, Pretty sure I have what you need on the heater container.
    Here is something for your OCD mood, if it gets you again.

    https://www.ebay.com/itm/TRIUMPH-TR3...xXkQVr&vxp=mtr

    Wayne
    '37 MG TA, '49 Triumph Roadster, '70 TR6, 2000 Jaguar XK8, '78 Spit6

  18. #18
    Jedi Knight
    Join Date
    Apr 2013
    Location
    redding,ca
    Posts
    1,067
    Thanks Thanks Given 
    1
    Thanks Thanks Received 
    11
    Thanked in
    11 Posts

    Re: wobbly exhaust manifold studs

    Note the description of the missing / cut off tab on the eBay part.
    Charley

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •