exhaust manifold bolt broke off - Diesel Forum

cartowing · 05-25-2005, 03:58 AM

Hello all I have a problem. the bolt near the firewall broke off on the pass side exhaust manifold going to the block. what is the best way to get whats left out. I havent taken it apart yet. 93 f450 7.3 none turbo. thanks Dean

argve · 05-25-2005, 06:42 AM

Is it flush with the block or can you tell?

Either way I would hose it down with PB Blaster and keep hosing it down... This stuff does wonders to rust.

If sticking out - yank manifold and get a good grip with a pair of vice grips then pour some heat on her and grunt...

Now if flush (if you luck it like mine it's either flush or broken down inside) then whip out the easy out (it's never easy and some one need to get a hold of the guy that named 'em that) - start praying and hope you don't snap the easy out. - fingers crossed for ya

Weezer · 05-25-2005, 07:56 AM

I've busted more Easy-Outs than had them work. Like travis said if you've got something left to grab on to, Vise Grip or I prefer a 6" pipe wrench- not as likely to slip. Either way, flush or stub left, like mentioned PB Blaster and it wont hurt to use a little heat (gentle now). Good luck,

Keith

perryg114 · 05-25-2005, 08:19 AM

I have had manifold bolts break off from fatique and they were still loose in the hole when this happened so they were easy to remove. If you broke it trying to get it out then you may have to drill it out. Believe me you don't want to try to drill it out once you have broken an easyout off in the stud. I usually start with a small bit then gradually go to a larger bit. Usually the broken bolt will start to rotate with the drill bit before you get to a drill bit that is as big as the internal threads. Once you got it free by drilling, use an easyout to remove it. If you damage the threads getting the bolt out you can helicoil it. Most of the time a tap will clean it up. Try to make the hole as close to the center of the broken bolt fragment as you can, a center punch helps.

Perry

agnem · 05-25-2005, 08:34 AM

Use a left hand drill bit with the drill in reverse if you can.

cdnsarguy · 05-25-2005, 08:45 AM

The manifold bolts on my 93 are ""factory special"" and have a triangular raised thread to lock them in place. This makes them a little harder to install and remove, it's like a lock nut effect.

Removing them will not be easy unless the shank is exposed. Couple suggestions:
If the shank is exposed use vice grips or weld a nut to the exposed end turn it out using heat.

If the shank is flush then drilling and an easyout is about all you can do...use reverse turning drill bits.

The exhaust manitold bolts have two types now OEM and updated.
OEM came with a special washer.

The updated bolts have a different head with the washer incorporated when checked they would be the same thread length so as not to bottom out.

New bolts are... F4TZ 9S425 B about $1.75ea

cartowing · 05-30-2005, 04:09 PM

hello & thank you all for the tips. I will keep you posted dean

dlblack · 05-30-2005, 10:05 PM

I have seen left handed drill bits at parts store where they have the easy outs. They might help.
Dwight

chumstone · 05-31-2005, 01:10 AM

a recent broken headbolt by a 6.9 poster was very informative. The thing I learned is to make sure you center the drill hole or your toast. [img]/ubbthreads/images/graemlins/smokin.gif[/img]

olivera149 · 05-31-2005, 06:49 AM

hey cartowing hope you got it, keep us updated if you got her and how, i like taking note of these type of things and i'm sure others do too.

--Ryan

Monte1 · 05-31-2005, 12:09 PM

Smart! I've never heard of LH drill bits! Wish I woulda known about 'em before I drilled out broken studs before. The only thing I can offer on this is to reinforce the point made to be VERY CAREFUL about drilling in the exact center of the stud. The only way to do this is to use a center punch and make your start in the center that way. If you don't, the drill will wander and you will end up drilling off-center.

icanfixall · 05-31-2005, 01:13 PM

The machine shop I work at just cut and drilled out 3 inch and 8 inch steam turbine studs. The large ones cost over $6,000.00 each and are harder than the wife when she says no to anything I want. I take it the head is still on the motor and the motor is still in the truck. Like said just try heat and the pipe wrench is the way I would go but a 3 inch may be a better choice with a cheater if needed. [img]/ubbthreads/images/graemlins/smokin.gif[/img]

dlblack · 05-31-2005, 10:23 PM

I saw the left handed drill bits at autozone.
You can also see the left handed drill bits on the McMaster Carr catalog http://www.mcmaster.com/ at the bottom of the page 2281.

If the broken bolt is in a hole you might try this.
Look at the McMaster-Carr catalog at the bottom of page 2130 you will see a center punch that you can put in a hole and find the center. There is a spring in the housing that centers when you push down in the hole and then center punch the place where you need to drill.
Or i have used a 3/16" drill in the center and started the hole.
It comes in 2 sizes.
You can see this at http://www.mcmaster.com/ on page 2130.
Hope this will help.
Dwight

cartowing · 06-09-2005, 03:34 AM

Hello every one thanks again for the great tips. after I got the manifold off it was pretty easy to drill a hole in what was left of the bolt & used an easy out to remove it. it really made my weekend when it just unscrewed easy. aloha from Hawaii Dean [img]/ubbthreads/images/graemlins/smile.gif[/img]