Dodge_48 Posted June 28, 2023 Report Posted June 28, 2023 Looking for simple dimensioned drawing for intake/exhaust manifold mounting stud spacing. Had to remove the manifolds to replace a bad gasket and 2 studs broke off just inside the block. Was planning to make a guide plate to bolt to the side of the block to guide drilling out the broken studs. Any other advice regarding this disaster would be welcome, as well. I thank you in advance. Quote
Solution moparfun Posted June 30, 2023 Solution Report Posted June 30, 2023 If you work on old stuff this happens, patience is what it takes to be successful with this issue. The following is what has worked for me, spray some penetrant and let sit then center punch make sure to be in the center of broken bolt. Start with a small drill bit and drill all the way through the bolt, once through you'll see how off center you are and that's ok it just limits the next size or the final size hole you can drill with out damaging the threads. Drill removing ass much of the bolt by drilling out with larger drill bit but staying away from the threads after use an easy out with success, like I said be patient Quote
Young Ed Posted June 30, 2023 Report Posted June 30, 2023 Before you get to drilling have you tried welding a nut to the broken stud? Quote
Dave72dt Posted June 30, 2023 Report Posted June 30, 2023 Getting good weld penetration on a nut first is difficult. Welding a washer on first will often do a better job, concentrates the heat on the stud. You can weld a larger nut or second washer to it if you feel you need it. If the stud is sunk in, you can concave the washer a bit with a ball peen hammer for easier welding. Welding washers on is my go-to choice , often needing only a good pair of pliers to work the broken bolt/stud out. Last choice is the drilling and tapping. Nuts aren't bad if you have a protruding piece of broken stud. When that breaks off flush, go back to the washer 1 Quote
Los_Control Posted June 30, 2023 Report Posted June 30, 2023 19 minutes ago, Dave72dt said: Getting good weld penetration on a nut first is difficult. Welding a washer on first will often do a better job, Thats a good tip to use a washer ..... I have had mixed results getting good penetration welding nuts on. Sometimes I do not get good penetration & it sometimes is a one shot deal. Suggesting if it does not work the first time, you end up grinding off the weld & drilling it out. ..... perhaps a washer for a base welded in first would help. I just ran into the issue last week, I welded a nut on a stud with complete confidence .... I'm getting a lot better with my welding I had cleaned my surfaces, I held the nut with vice grips, I turned the welder on & welded the crap out of it. Thing is, the last time I used the welder was welding in 20 gauge sheet metal & had the heat turned way down ..... I never adjusted my heat settings to weld the nut on. I'm only suggesting, a good qualified professional welder would have no problems getting proper penetration on that weld the first time. For those of us who do not weld professionally .... the washer is a good buffer & possibly gives you 2nd chances ..... I will have to try it. Quote
47 dodge 1.5 ton Posted July 1, 2023 Report Posted July 1, 2023 If you still try using a template, be cautious because you will not be able to see that well through any fixture. I recommend using left hand drill bits on whatever process you use as most of the time will spin the old stud out. Quote
Dodge_48 Posted July 1, 2023 Author Report Posted July 1, 2023 23 hours ago, moparfun said: If you work on old stuff this happens, patience is what it takes to be successful with this issue. The following is what has worked for me, spray some penetrant and let sit then center punch make sure to be in the center of broken bolt. Start with a small drill bit and drill all the way through the bolt, once through you'll see how off center you are and that's ok it just limits the next size or the final size hole you can drill with out damaging the threads. Drill removing ass much of the bolt by drilling out with larger drill bit but staying away from the threads after use an easy out with success, like I said be patient 16 hours ago, Dave72dt said: Getting good weld penetration on a nut first is difficult. Welding a washer on first will often do a better job, concentrates the heat on the stud. You can weld a larger nut or second washer to it if you feel you need it. If the stud is sunk in, you can concave the washer a bit with a ball peen hammer for easier welding. Welding washers on is my go-to choice , often needing only a good pair of pliers to work the broken bolt/stud out. Last choice is the drilling and tapping. Nuts aren't bad if you have a protruding piece of broken stud. When that breaks off flush, go back to the washer I definitely considered welding. The issue is that they both broke just below the surface of the block, and I was worried whether it’s possible to get any weld bonding to the cast iron. I haven’t done anything yet- just waiting on advice. I do not want to make this worse than it already is. On that account, I’m worried about drilling too. Because the studs are hardened, I’ll need cobalt bits, and they’re brittle. If you break a bit off while drilling, how do you get that out? Same goes with the tap. Jeez. What a predicament. Quote
Plymouthy Adams Posted July 1, 2023 Report Posted July 1, 2023 if bolt broken off in cast iron, blind or through hole, blow the hole with oxygen/acetylene torch.... Quote
kencombs Posted July 1, 2023 Report Posted July 1, 2023 (edited) 32 minutes ago, Plymouthy Adams said: if bolt broken off in cast iron, blind or through hole, blow the hole with oxygen/acetylene torch.... That works well, IF you have the tools. Works even better it you drill a pilot hole in the stud to start the cut, less blowback. Lacking the torch, I've use the DeWalt pilot point drill bits. Where possible use the manifold as a drill guide Edited July 1, 2023 by kencombs Quote
Los_Control Posted July 1, 2023 Report Posted July 1, 2023 I was looking for a particular video ... this guy was a diesel mechanic & he showed different ways he removed broken intake bolts. I found this one instead, guy had some good tips ... looks like he knows what they are doing. He is working on a aluminum head but is same for cast iron. .... He adds weld to the bolt to get it above the surface .... claims it wont stick to the cast iron. You do want to be careful & try not to weld directly on the cast iron of course. Might be worth a few minutes to watch, I got something from it. Quote
Dave72dt Posted July 1, 2023 Report Posted July 1, 2023 welding is no more damaging than blowing than blowing it out with a torch. concave a washer by placing it on a socket, ball end of a ball peen hammer centered in the washer and a tap or two on the hammer, ( I know, hammer against hammer but you're not going caveman on this), weld it to the broken stud, hot weld, weld a second washer to the first washer, again hot.. Once the red is gone you can start working it out, penetrant, candle wax, etc.. repeat process if necessary. Try it with a good pair of pliers first, not a vise grip style. You're more likely to break the weld loose with a vise grip. You can repeat heating the stud with more weldon the washers if it doesn't break loose. 1 Quote
Dodge_48 Posted July 1, 2023 Author Report Posted July 1, 2023 I’m not a welder and still a bit concerned with cast iron as a base, so I’ll get my bro in law to do it. Perhaps going with a 5/16 washer would help to prevent the weld from getting near the cast iron, and cupping the washer seems like a great idea for a stud broken off a bit shallow. Stacking washers a couple times if it doesn’t come out with pliers seems like a good idea, since heat and cold cycles supposedly help break it loose. Finally, after a couple cycles with the washers, I’ll try welding on a nut and apply a bit more torque. It only makes sense to try welding first. Hopefully, the worst case is the stud refuses to come out, the nut breaks off and I eventually end up having to drill it out, and in the worst case of all, perhaps install a helicoil. I want to avoid damaging the block at all cost. Opinions? Quote
Dave72dt Posted July 1, 2023 Report Posted July 1, 2023 You already have mine. Been doing them this way for 45+ years, originally with a stick welder. I do use screw extractors on occasion, usually for broken hydraulic pipe fittings that were snapped off in a hydraulic cylinder and there are some tricks to making them work better also. I've tried the left handed bits also with very limited success. Quote
Los_Control Posted July 1, 2023 Report Posted July 1, 2023 (edited) The thing with a broke exhaust bolt ....most of the time the threads are good & not damaged. The bolts are weakened & rusted so easy to break. Once the head is gone that does apply the pressure to tighten the bolt ..... now it is just the bolt no longer tight except for the rusty threads. Welding to the bolt will create the red hot heat that will usually break the bond of the rusty threads. Allowing the bolt to be removed. I think you are spot on with your worse case scenario. .... A lot depends also on how much access you have .... I assume the engine is installed & you have the inner fender removed to get to it? The other day I had to drill a bolt out of a nut ...... I had a floor pan I was preparing to weld into place. I ordered some U-clips that needed to be installed first & the provider never shipped them & was holding me up .... I decided to weld some nuts to the floor pan. This is fine, I drilled the holes in the pan then tightened the nut/bolt into place & welded them .... Perfect solution. I should have tacked the nuts in place then remove the bolts ...... I fully welded the nuts in place then removed the bolts. I got the nuts so hot I destroyed the threads on 2 of 4 bolts. 3 of 4 came out alright, 1 broke. .... Because of the damaged threads, I tried to weld a nut to it but it was not coming out that way .... I had to drill it. I got as close as I could with drill bits, then I used my dremel tool with a pointy carbide bit & removed the rest of the bolt .... you could see the shadow of the threads it was so thin. Then I used a small pick to get behind the thin metal that was left & pried it out of the threads, then used needle nose to grab & pull it out. I did run a tap down the nut when finished .... all is good. Only point here, I damaged the threads with heat, no way I could weld a nut on & turn it out. .... Was more work & I learned a lesson. Your threads are not damaged, they just have a bond on them from age & rust, they should turn out. There are still other ways to fix this .... my way I just used is not great, but it did work. Edited July 1, 2023 by Los_Control Quote
Dodge_48 Posted August 19, 2023 Author Report Posted August 19, 2023 On 6/30/2023 at 2:40 PM, Dave72dt said: Getting good weld penetration on a nut first is difficult. Welding a washer on first will often do a better job, concentrates the heat on the stud. You can weld a larger nut or second washer to it if you feel you need it. If the stud is sunk in, you can concave the washer a bit with a ball peen hammer for easier welding. Welding washers on is my go-to choice , often needing only a good pair of pliers to work the broken bolt/stud out. Last choice is the drilling and tapping. Nuts aren't bad if you have a protruding piece of broken stud. When that breaks off flush, go back to the washer Ok, so I’ve been tied up and just got to the 2 broken studs. Here’s how it went: one stud was flush and one was broken below the surface. I took Dave72dt’s advice and welded washers to them. One washer I dished to try to get it as close to the stud as possible. I used slip joint pliers on the studs to work them back and forth in conjunction with penetrating oil. The stud that was flush freed up by carefully working it back and forth until it felt free enough to finish removing. The second one felt the same, but after working it back and forth a couple times, it let go. Since it was now even further retracted from the surface (looked close to 1/4 inch), I decided against attempting to weld to it again for fear I might damage the cast iron. I drilled it and worked on it with a Dremel tool to get the remainder out. Unfortunately, I did have to get into the threads a bit because the Dremel and a tap just didn’t want to get all the old threads out. The washer idea was really good. Thanks for the help, Dave72dt! In retrospect, I might have tried another washer on the second stud. It’s possible that I was just twisting the end of the bolt when I was working it back and forth, though it didn’t seem like I was going after it with enough force. Oh well. I’m now looking at a helicoil in that second stud to ensure the new stud holds. Question: use a stainless helicoil from McMaster Carr, or standard helicoil from automotive supplier, which is likely made in China? Quote
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