madspikes 41 1 Cars Posted May 19, 2007 Can anyone offer any advice? While removing the exhaust manifold I snapped off one the manifold studs flush with the head! Its one of the two lower ones in the middle, where there are two blots close together. Can I run without this 8th bolt or do I have removed the head and get the bugger out. I do expect the engine to be rebuilt next year after I blow the hell out of it the with super-charger, so it would be a 'temp' fix! Mad. Share this post Link to post Share on other sites
welshpug 1,657 Posted May 19, 2007 no, it wont seal. you wont have to take the head off though, just take the engine out in one lump, a lot easier. Share this post Link to post Share on other sites
lagonda 42 Posted May 19, 2007 Hi, When I took my head off after head gasket failure, I found one of the 2 studs you mention was broken. There was no evidence of blow-by, so the short answer is, yes, you'll probably get away with it. I think it helped that the 2 studs are so close, so the affected area benefits from neighbouring torque so to speak. I'd be less confident if it was any of the other studs for that reason. Share this post Link to post Share on other sites
johny105_y2k 1 Posted May 19, 2007 should be fine. i know the ones and they are buggers for snapping Share this post Link to post Share on other sites
Grim.Badger 15 Posted May 21, 2007 You might be fine with it being a central bolt but I'd use a load of sealant as well to be sure; personally one of my dreams is to have a manifold that doesn't blow but then I'm too cheap to get any sealant Share this post Link to post Share on other sites
ALEX 98 1 Cars Posted May 22, 2007 The reason nut & studs are used instead of scews is so you can torque them up more without the risk of ripping the therads in soft alloy head. Share this post Link to post Share on other sites
TEKNOPUG 3 Posted May 23, 2007 The reason nut & studs are used instead of scews is so you can torque them up more without the risk of ripping the therads in soft alloy head. If only that was true Share this post Link to post Share on other sites
tom_m 0 Posted May 23, 2007 You might be fine with it being a central bolt but I'd use a load of sealant as well to be sure; personally one of my dreams is to have a manifold that doesn't blow but then I'm too cheap to get any sealant a fiver down halfords for a tube of loctite 5920 and your dreams could be reality. it sealed my magnex with one of the outer studs missing when nothing else would i don't care how cheap you are, that sounds like a good deal to me! Share this post Link to post Share on other sites
TEKNOPUG 3 Posted May 23, 2007 Did you use the sealant whilst the manifold was still in place or did you remove it first? Share this post Link to post Share on other sites
ALEX 98 1 Cars Posted May 24, 2007 If only that was true It is Share this post Link to post Share on other sites
TEKNOPUG 3 Posted May 24, 2007 Doesnt really explain why one of my studs has stripped the thread from the soft alloy head. Share this post Link to post Share on other sites
madspikes 41 1 Cars Posted May 24, 2007 a fiver down halfords for a tube of loctite 5920 and your dreams could be reality. it sealed my magnex with one of the outer studs missing when nothing else would i don't care how cheap you are, that sounds like a good deal to me! I think I'll give this a bash,I just know that drilling out the broken stud will end in a whole world of pain, so loctite it is! I know with the state my car is in it would be easy to pop the engine out, but I dont want to at this point in time. I get the feeling I'll never finish my car at this rate! Mad. Share this post Link to post Share on other sites
tom_m 0 Posted May 24, 2007 Did you use the sealant whilst the manifold was still in place or did you remove it first? i dropped the manifold off the back of the head and applied a generous (but no too generous) amount of sealant to the mating face. Share this post Link to post Share on other sites
ALEX 98 1 Cars Posted May 24, 2007 Doesnt really explain why one of my studs has stripped the thread from the soft alloy head. O.K. then.... The reason nut & studs are used instead of screws is so you can torque them up more with less risk of ripping the threads in soft alloy head. Sounds like you were just unlucky, maybe because the nut was rusted to the stud, but nuts generally fail first. Even though nuts are harder than the thread in the head you still have 25mm of soft thread verses 7mm of hard thread. With using just screws the head will always fail first, So in short using screws rather than studs is a bad idea. Share this post Link to post Share on other sites
TEKNOPUG 3 Posted May 24, 2007 O.K. then.... The reason nut & studs are used instead of screws is so you can torque them up more with less risk of ripping the threads in soft alloy head. Sounds like you were just unlucky, maybe because the nut was rusted to the stud, but nuts generally fail first. Even though nuts are harder than the thread in the head you still have 25mm of soft thread verses 7mm of hard thread. With using just screws the head will always fail first, So in short using screws rather than studs is a bad idea. LOL - I'm just messing with you Alex. It was done by a previous owner. They fitted a new head but didn't increased the studs to M10 as per TT conversion. They then overtightened one of the studs and stripped the thread. A real pain in the ass as I'm gonna have to remove the head to get it fixed. Share this post Link to post Share on other sites
stevec205gti 0 Posted May 24, 2007 O.K. then.... The reason nut & studs are used instead of screws is so you can torque them up more with less risk of ripping the threads in soft alloy head. Sounds like you were just unlucky, maybe because the nut was rusted to the stud, but nuts generally fail first. Even though nuts are harder than the thread in the head you still have 25mm of soft thread verses 7mm of hard thread. With using just screws the head will always fail first, So in short using screws rather than studs is a bad idea. I thought studs were used because it's a lot easier to hold the manifold in place before bolting it down blind with a positive location feature- and the easiest way of putting a positive location feature in place from the head is with studs. Share this post Link to post Share on other sites
pug_ham 244 3 Cars Posted May 25, 2007 I've removed three manifolds that have had only seven studs holding the exhaust manifold on, the missing one was in various different places, either at #1 or #4 cylinder exhaust or once between #2 & #3 cylinder. Neither manifold was blowing, even on the ones with a stud on the end missing. Graham. Share this post Link to post Share on other sites
Grim.Badger 15 Posted May 25, 2007 I've removed three manifolds that have had only seven studs holding the exhaust manifold on, the missing one was in various different places, either at #1 or #4 cylinder exhaust or once between #2 & #3 cylinder. Neither manifold was blowing, even on the ones with a stud on the end missing. Graham. Are you sure the gaskets hadn't rusted into place on them though I ran with seven on my last engine and noticed a month or so after doing the job that the gasket had slipped and was partially covering one of the ports needless to say it blew a lot. I've got 8 on now but one has a damaged thread and the manifold face isn't exactly smooth so it still blows Share this post Link to post Share on other sites
pug_ham 244 3 Cars Posted May 26, 2007 Are you sure the gaskets hadn't rusted into place on them though I ran with seven on my last engine and noticed a month or so after doing the job that the gasket had slipped and was partially covering one of the ports needless to say it blew a lot. The stud hadn't sheared flush with the head on the ones with a stud missing on #1 or 4 cylinder so the gasket was still held in place correctly & the one with the centre stud sheared was still clamped tight enough for it not to move. Graham. Share this post Link to post Share on other sites
