I have a generic question regarding broken manifold bolt at rear of head. Unable to access the area without removing the manifold and possibly the head. I have heard of guys using DOTCO 90 right angle drills at a low rpm to get into those otherwise unreachable places. At 600-1000, rpm, drill a series of three holes, each getting bigger, until you can insert an ez out and back out the broken bolt. If this does not work, remove the manifold and possibly the heads. Has anyone ever tried this? The cost of a used DOTCO 90 is anywhere from $100 to $300. Used, they are between $500 and $700, depending on the model and rpm.

Darrell Howard Whitefish, MT Outlaw 56 Ford F-100's

Seems like removing manifold and heads would be easier. I have never had to do that before but I would opt for removal.

55Birdman  Hickory NC

I have had to drill out broken bolts in the past with parts on vehicles  and i can say for certain it would be way easier to remove the head and drill as birdman has pointed out . If you stop and think about it , you could buy all the gaskets  you need for less than the cost of the tool and you'll be working  comfortably on a bench rather than laying over a fender .  Good luck 

Is the bolt even with the top of the manifold? If so, weld a washer to the bolt and then weld another bolt to the washer. This gives you a bolt to turn with a wrench.

54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

Unfortunately, this is not an issue with one of 56 Ford F-100's. Its a fuel injected 2000 Chevy 6.0. Its more than I do myself, or at least than I am comfortable with. I assume the cost do have a mechanic do it would be $600-$1000 bucks.

Darrell Howard Whitefish, MT Outlaw 56 Ford F-100's

Back when Kelly AFB was still in operation in San Antonio, Dotco right angle drills appeared in pawn shops all the time. I have several of them. They are handy at times, but drilling out a hard to get to manifold bolts was not one of the handy times. They are very handy for drilling aluminum rivets on our trailers in awkward spots and I think they were probably designed for aluminum air frames. I have gotten studs out by carefully burning a hole in the middle of them with a torch and splashing water on them. I left thread eze out removed them quite easily then. I would only recommend that on an old jalopy that I had spare parts for.

Kenneth

Fredricksburg, Texas

I would think that if Paul 2748's solution is workable in this case, it would not cost anywhere near $600 and up. On the other had if that engine is one with a plastic intake, all bets are off..

Paul

We run into broken exhaust manifold bolts on 5.4 & 6.8 F-Series pick-ups all the time. We usually pull the plastic inner fender and have a straight shot at drilling the broken bolt. We also replace the exhaust manifold because its usually warped.

Dan      Kingman Az.      86409

The  manifold bolt is broken off between the head and the manifold. It appears to be flush with the surface of the head. Its the rear manifold bolt on the driver side, which access is restricted by the firewall. I have found a guy on ebay who has used  low RPM Dotco drills before to remove manifold bolts in similar locations with sucess. I think this is a long shot, but I will fab a bushing with a small hole in the center to center the drill bit and press it into the empty hole in the manifold. This should increase my chance of getting a bit up against the broken surface of the bolt and start a hole in the center without damaging the threads in the head.  

I found a used drill that includes bits and ezeout for $250.00. I am skeptical it will work, but willing to take the risk. If it dosen't work, I can always unload the drill on ebay for close to what I paid for it. I believe the clearance necessary to to use this drill is just a little over two inches.  Thanks everyone for your suggestions and I will let everyone know how this worked.

Darrell Howard Whitefish, MT Outlaw 56 Ford F-100's

Hey Outlaw,

There are tap extracting services available, they "burn" out the bolt using an EDM machine. I had a broken bolt in my trans tailhousing and I broke an ez out in it. I took it to one of these services and it cost me 36 dollars and was done the next day. He burned the ez out out too. The only thing is you gotta remove the head so they can set it up on the machine, you can leave the rocker arms and valves in too. I don't know where you live, but if you live in so cal I can refer you to this guy. Just an alternative to spending a bunch of money and still may not be able to get it out.