Common problem with older Dakotas, as the exhaust flange rots through, and the bolts often break offI just bought this 1995 Club Cab 4x4 and it has two broken exhaust manifold bolts on the passenger side. Is there any special advice to get them out except to drill and extract?
Now THAT'S some great info buddy and the video, leaves no doubt about how it's done (if there was any question). Great for you to post that info.Common problem with older Dakotas, as the exhaust flange rots through, and the bolts often break off
because they are heat seized in the manifold.
Since the threads are heat seized/rusted in over the years, drilling and using an screw/bolt extractor isn't going to work, because even if you drill most of the bolt out..(big job and you will break a few drill bits!),
the extractor isn't going to be able to break the rust bond on the threads.
If you drill out the thread too, you will have more problems as well because these
are cast iron manifolds and rethreading with a thread chaser is not necessarily a good idea.
The best thing is to take it in to a garage that has a oxy-aceytlene torch and heat up both bolts (one at a time) cherry red, and either apply wax or penetrating oil and try to extract what's left of the bolt with a curved jaw water pump or grip pliers. You have to work the bolt back and forth on it's thread to loosen it.
I had the flanges and bolts on mine replaced that way recently.
Also, use Grade 5 bolts by the way, because a lower grade bolt shear strength will snap off there,
when you go to torque it up.
here's a video on how one guy suggests to do it..
Not sure about the scenario, but the job is difficult enough without having moreThe bolts are broken off in the head where the manifold bolts to the head. On the passenger side manifold there are 4 bolts that fasten the manifold to the head and it is the front two that are broken off. Does that make this a different senario for getting them out?
That welding method is EXACTLY what I would recommend, it has never failed me. I've used different methods of heating & cooling to try to break the rust bond - propane has never worked and oxy-acetylene can ofen do more harm to the stuck bolt. The welding process shown in the video does a good job in extreme local heating that often breaks the seized bolt loose on the first try. I know quite a few fabricators that use only the nut (no washer) and they need to re-do the process much more often since it's harder to get a good bond to the broken bolt just through the hole in the nut - I modified my technique years ago & am glad to see that someone was able to put this on video.Then there is the welding method of extraction. While it is a shameless
plug for a welding shop, it may give you an idea of how to do it with
Depending on how rusted the threads are..some heat on the stud to warm it up
may be necessary. Heat it up with a propane torch and when it cools down a bit
squirt some penetrating oil into the threads of the broken stud to unseize it for easier
Not only drilling in tight spaces with a standard variable speed drill atThat welding method is EXACTLY what I would recommend, it has never failed me.
Using extractors can add to your problem, especially for smaller sized bolts & I put anything 3/8 and down in that category. It doesn't take much to snap the smaller extractors leaving you with only the welding method left.
I fully agree with all your statements on attempting to drill and extract - I've had personal experience with failed attempts at trying to get an exact center (I came up with a few solutions for this, all of which require quite a bit of extra work) and then to try to drill along the exact line on the original bolt (this wasn't as easy), and finally, capping things off with experiences with broken extractors made me a firm believer in the welding techniques. I tried using various forms of gas such as Propane MAP, Oxy-Propane, and Oxy-Acetylene and found that the hotter gases were better but they all tended to heat the broken bolt at a pedestrian pace, so the shock effect of having one part expand/contract at a much greater rate than an attached part was lost. Using a MIG makes it very easy to focus the heat right onto the broken bolt & the washer protects the surrounding cast block and makes a great foundation for the nut. The whole surface of the washer is exposed to the welding process, so you can easily melt the washer to the bolt AND give the bolt the thermal jolt it needs to loosen it's oxidation bonds. I let the whole thing cool (I encourage the cooling process after the afterglow is gone with a slight stream of water right onto the weld - I don't soak the whole area, and it gives me something to do while watching "paint dry"), and then I take the next step with the nut - weld it in the center if I can, and then weld it at the bottom to the washer & again I let things cool. At this point, the errant bolt normally comes out on the first try. I found that by using a thick washer, I get a much better bond to the bolt - the "trick" here is to be careful not to melt the bolt into the block - doing this normally means that after bolt extraction, you're into making the hole larger and installing a helicoil insert.Not only drilling in tight spaces with a standard variable speed drill at
ackward angles but keeping the drill bit straight is going to be a problem.
Centering a small diameter drill bit on a exhaust stud that is not perfectly flat, could end up with some grief as the drill bit will skate (wander) off center. Even if you manage to continue without breaking the drill bit, it could be way off center, and you end up drilling some threads out on the threaded hole where the stud is. At this point, you are going to have some real issues with a stud extractor, even if it's close to the proper size, as the extractor is not centered in the stud anymore.
And if you snap off a smaller extractor..very hard steel..you won't be
able to drill it out anymore..then the smaller problem becomes a major
problem at that point.
This is a good discussion on the most productive and least frustrating approach to removing broken exhaust studs.
Thanks that is a great explanation Cap'n.At this point, the errant bolt normally comes out on the first try. I found that by using a thick washer, I get a much better bond to the bolt - the "trick" here is to be careful not to melt the bolt into the block - doing this normally means that after bolt extraction, you're into making the hole larger and installing a helicoil insert.
I'll answer your question in a round-about manner. I look at impact wrenches from a different perspective, in both electric (battery & corded) and pneumatic, you'll find the high & low beats-per-second (bps) wrenches & when I'm trying to remove something that I know has been sitting for a long time (possibly seized) or is normally installed with a mid to high torque, I prefer a low bps & high max torque unit. If I'm installing or removing something that's new and/or with clean threads and no thread locker or high torque installation, I prefer the lower torque, high bps units because they're smaller & lighter to use & you don't need to worry about overtorque situations. In my tool box, I have an Ingersal Rand low bps 600 ft.lb. max torque pneumatic, Dewalt corded low bps 350 ft.lb. max torque (I don't use this one much anymore), Dewalt 18V low bps 350 max torque and a Dewalt 18V high bps 110 ft.lb. max torque. To minimize the number of tools but to give yourself the best spread of capability, I'd recommend a pneumatic low bps of at least 500 ft.lb. (many wrenches on the market are pretty dismal in performance - Ingersal Rand, in my opinion, gives you the best bang for the buck) and a small battery powered high bps 100+ ft.lb. unit (get one with 2 batteries & a charger),Thanks that is a great explanation Cap'n.
This should be on the FAQ (if we had one) along with some of the other frequently asked questions about common problems.
A question to you.
After doing the MIG welding and letting the stud cool..is it better to use a electric (or pneumatic) impact tool to loosen the stud with the nut welded on?
Thanks. That was the simple answer I was looking for. You are a veritableNow that I've given you my impact wrench preferences for various jobs, I'll answer your "broken bolt removal" question - I would start with a ratchet & socket (maybe a breaker bar) and give the bolt a few reasonably hard tugs first.
So the long and short of it is..for broken exhaust studs, unless you haveOften I'm pretty lucky and the bolt spins out and if it doesn't, this gives me an idea of how good my weld was and for the more stubborn bolts, I'll use a low bps, high torque wrench to apply the extra shock value. If I really go to the "grunt stage" with a breaker bar, I'm afraid I'll twist off the nut, washer, and another piece of the stuck bolt & with another piece of the bolt gone, it makes it more difficult to weld the next washer on without damaging the block threads. Sometimes the bolts are bad enough where I would need to re-heat (with the MIG) or replace the nut one or two more times to get it out. This is a job where preparation and patience are key, and the worse the bolt, the more patience you need.
Good info again.On the subject of bolts, I'd recommend using the impact wrench for a lot of situations, such as body mount bolts (the front ones on a Dakota will often spin if you use a breaker bar), torx bolts that have been exposed to the elements (you'll strip the splines with a ratchet and torx bit), etc.