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how to fix/replace exhaust manifold stud
kp - 29/8/12 at 10:14 AM

In addition to my other engine problems (
no compression), One of the exhaust manifold studs has sheared off flush with the head. The engine is a sohc pinto 1.6l.

My questions;
1. how do I get the broken stud out (I have a drill press, if that helps)
2. do I replace the stud (how?)
3. or can I just tap the hole and use a bolt

[Edited on 29/8/12 by kp]

steve m - 29/8/12 at 10:42 AM

You may be lucky, if its not tight to be able to tap it anticlockwise with a centre punch or chisel

if not drill a hole in the middle, and an easy out screwed in ?

If not its a drill out till you get to the thread, and helicoil

others, may have some better ideas! but this was my process's

twybrow - 29/8/12 at 10:58 AM

Given the problems you have with this engine, would it not be easier and quicker just to replace the engine with another Pinto lump?!!

mookaloid - 29/8/12 at 11:32 AM

Much the best way to get broken studs out is to put a nut over the end of the stud then weld the end of the stud to the inside the nut with a mig.

The welded on nut gives something to put a spanner on and the heat of the welding generally unsiezes the threads on the stud.

Simples

steve m - 29/8/12 at 12:06 PM

spot the word that gives it away

"One of the exhaust manifold studs has sheared off flush with the head"

mookaloid - 29/8/12 at 12:14 PM

quote:
Originally posted by steve m
spot the word that gives it away

"One of the exhaust manifold studs has sheared off flush with the head"


Not sure what you alluding to here?

twybrow - 29/8/12 at 12:41 PM

quote:
Originally posted by mookaloid
quote:
Originally posted by steve m
spot the word that gives it away

"One of the exhaust manifold studs has sheared off flush with the head"


Not sure what you alluding to here?


Pretty tricky to put a nut over the end of the stud and weld it when it is flush with the head!

blakep82 - 29/8/12 at 12:46 PM

quote:
Originally posted by twybrow
quote:
Originally posted by mookaloid
quote:
Originally posted by steve m
spot the word that gives it away

"One of the exhaust manifold studs has sheared off flush with the head"


Not sure what you alluding to here?


Pretty tricky to put a nut over the end of the stud and weld it when it is flush with the head!


difficult to screw it on yes, but not difficult to place it over the end of the stud, which is enough to get a weld on it.

mookaloid - 29/8/12 at 01:07 PM

quote:
Originally posted by blakep82
quote:
Originally posted by twybrow
quote:
Originally posted by mookaloid
quote:
Originally posted by steve m
spot the word that gives it away

"One of the exhaust manifold studs has sheared off flush with the head"


Not sure what you alluding to here?


Pretty tricky to put a nut over the end of the stud and weld it when it is flush with the head!


difficult to screw it on yes, but not difficult to place it over the end of the stud, which is enough to get a weld on it.


I guess those doubters have never tried to do this.

I have on many occasions removed studs when they have broken flush with whatever they are in using this method. It is a very good method and I suggest you give it a go before taking the p***

twybrow - 29/8/12 at 01:16 PM

quote:
Originally posted by mookaloid
quote:
Originally posted by blakep82
quote:
Originally posted by twybrow
quote:
Originally posted by mookaloid
quote:
Originally posted by steve m
spot the word that gives it away

"One of the exhaust manifold studs has sheared off flush with the head"


Not sure what you alluding to here?


Pretty tricky to put a nut over the end of the stud and weld it when it is flush with the head!


difficult to screw it on yes, but not difficult to place it over the end of the stud, which is enough to get a weld on it.


I guess those doubters have never tried to do this.

I have on many occasions removed studs when they have broken flush with whatever they are in using this method. It is a very good method and I suggest you give it a go before taking the p***


Easy Mookaloid - no one is taking the pee - I was not sure you had noticed the 'flush' part in the OP, so apologies if by making it clear I offended you! I have tried it before on several occasions, and have had mixed success - I found the issue was ensuring a good weld with the very first arc, as otherwise, all you do is shear the welded nut straight back off again. You also risk accidentally welding the head/thread particularly where it is flush, or just below the surface, so it is not a case of just having a go IMHO. If the OP has access to a welder, then it might well be a reasonable technique to try, although I would try the drilling/tapping method first personally....

mookaloid - 29/8/12 at 01:23 PM

quote:
Originally posted by twybrow


Easy Mookaloid - no one is taking the pee - I was not sure you had noticed the 'flush' part in the OP, so apologies if by making it clear I offended you! I have tried it before on several occasions, and have had mixed success - I found the issue was ensuring a good weld with the very first arc, as otherwise, all you do is shear the welded nut straight back off again. You also risk accidentally welding the head/thread particularly where it is flush, or just below the surface, so it is not a case of just having a go IMHO. If the OP has access to a welder, then it might well be a reasonable technique to try, although I would try the drilling/tapping method first personally....


In fairness you only said you though it would be tricky - which is fair enough. If you can't weld/don't have access to a welder then obviously it isn't a viable option. I think the sarcasm evident in the other guys post was unwarranted though.

kp - 29/8/12 at 02:01 PM

Thanks for all the replies.

I took the manifold off today and found that the stud was NOT flush with the head, there is at least 1/2 thread left on the stud. That should make it easier.

I can probably tap a few more threads on it. If I can get two nuts on it will I be able to screw out the stud (I assume it screws out anti-clockwise)?



Apologies to all, I don't know why I thought it was flush.
[img][img]http://www.flickr.com/photos/kenpower/7887293662/[/img][/img]

[Edited on 29/8/12 by kp]

steve m - 29/8/12 at 02:06 PM

Oh dear,

sorry for my post

mookaloid - 29/8/12 at 02:14 PM

quote:
Originally posted by steve m
Oh dear,

sorry for my post


No worries mate - thank you for saying that - plenty of people wouldn't have

Bare - 29/8/12 at 05:25 PM

quote:
Originally posted by kp
Thanks for all the replies.

I took the manifold off today and found that the stud was NOT flush with the head, there is at least 1/2 thread left on the stud. That should make it easier.

I can probably tap a few more threads on it. If I can get two nuts on it will I be able to screw out the stud (I assume it screws out anti-clockwise)?



Apologies to all, I don't know why I thought it was flush.
[img][img]http://www.flickr.com/photos/kenpower/7887293662/[/img][/img]

[Edited on 29/8/12 by kp]


Seriously? I would without hesitation Drag your car (or it's Cyl head at least ) to a decent shop and have them attempt the Stud extraction .
Some things ARE worth paying for Skilled help.

rusty nuts - 29/8/12 at 07:09 PM

What ever you do don't bother with so called easiouts, the best place for them is in the bin. As already suggested it is possible to weld a nut on a stud that has broken off flush , sometimes you may have to weld on several nuts before you are able to remove the stud. This also works with siezed bleed nipples. With the head off it should be easy to drill the stud centrally so that you are able to retap the hole or if needed fit a helicoil. As others have suggested you may be better off fitting another Pinto lump, possibly a 2 lt?

kp - 29/8/12 at 07:38 PM

quote:
Originally posted by rusty nuts
What ever you do don't bother with so called easiouts,


Can't agree more, those things are useless.

quote:
Originally posted by rusty nuts
As others have suggested you may be better off fitting another Pinto lump, possibly a 2 lt?


Would love to put a 2.0L in, but pintos of any size are very hard to get here in ireland. 2.0l units are incredibly rare. That's why I'm putting so much work into this one.

kp - 31/8/12 at 11:04 PM

Thanks for all the advice everyone.

I managed to get a nut welded onto the stud. Came out easy as you like after that. I guess the heat helped.

RichardK - 1/9/12 at 12:29 AM

Haha too late again, I've always tried the nut thing with about 80% success.

Glad you got it out.

Love

Rich

enginearin - 23/10/12 at 08:39 PM

Hello all,

I've got a similar problem with a broken stud on my blade engine.

I've got an additional problem... I'm a novice (read useless) welder! I've tried welding on a few nuts tonight, but I don't seem to get enough penetration into the stud so the nut shears off.

If my stud is about 6mm diameter should I be using a small nut for a tight fit, or should I be trying a much larger nut with a gap to fill.

Also, should I be cranking the welder up to max to get the penetration into the stud? (Its a sealey supermig 180 with co2)

Thanks

Tim