How would you repair broken manifold bolts on a Cat 953 3204 engine?

Georgia Iron said: I tried a 6010 rod and a 7018 rod and the washer on the last attempt. Once when I was tapping the weld flux/carbon off the bolt just snapped. The bolts where very brittle. But they were surprisingly easy to drill out. I sharpened the bit about 4 times for each bolt and stepped up in drill sizes. What actually got me was I should have slowed down and looked the old manifold over better before I tackled the center bolts. The drilling out was later in the second day. I was thinking they would let go and come loose but they did not. I did use a guide to set my puch mark but as it started cutting it moved just a little. I also thought they were all short bolts, so close, would have been fine. Those being so long made the tolerances much more important. Click to expand... The problem with the 6010 rod is its not strong and no flexibility. HPM 1000 is 135000-140000 strength and very elastic. There are a few other companies that sell small packets of the quality high strength rods. Run with what you have now and you can always do the other style repair another time if down time is not too bad. Simon C

By the way there is one for 3204

pittsburgh cat man said: By the way there is one for 3204 Click to expand... Have to add that to the info stash

Just a little side thing that you might like to get sorted is the exhaust manifolds for these engines can fit both ways, so that is stick it on the head it will fit but turn it end over it still fits, the thing is it should only fit 1 way and by fitting it incorrectly you get gasket and bolt problems from the heat, on the broken studs well it's all been well covered by other people and all I can say is you should of asked after you snapped off the first bolt how best to go forward, they would have possibly come loose with the right application, in the end they would drill out easily I do this task often with good results, you can correct damaged holes with the Heli Coil type fix at worst, the parts listing of the manifold will show you the correct setting for it, don't get it wrong chap . best of luck tctractors.

Simon C said: The problem with the 6010 rod is its not strong and no flexibility. HPM 1000 is 135000-140000 strength and very elastic. There are a few other companies that sell small packets of the quality high strength rods. Run with what you have now and you can always do the other style repair another time if down time is not too bad. Simon C Click to expand... 610 rod are made for D.C. power really, an inverter type welder will struggle to fire them, 7016 or 7018 are the boys and they put a lot of heat into the job, my preferred rod is the 7016 as they reach the 7'000ps better than 7018, the higher strength rods are not easy to pick up in General Store's

tctractors said: 610 rod are made for D.C. power really, an inverter type welder will struggle to fire them, 7016 or 7018 are the boys and they put a lot of heat into the job, my preferred rod is the 7016 as they reach the 7'000ps better than 7018, the higher strength rods are not easy to pick up in General Store's Click to expand... There is quite a few suppliers of Rod made especially for welding out broken bolts, such as Inweld, Eagle Alloys, Xergon and some others. Some sell by small packets, others by the Pound or box. I have used many times with success. Have also done with 7018 and sometimes was good also. Simon C

Specialty rods are usually 120-130,000 tensile and will list for hard to weld steels, spring steel and broken bolts. They are stainless based similar to 312 stainless.

tctractors said: Just a little side thing that you might like to get sorted is the exhaust manifolds for these engines can fit both ways, so that is stick it on the head it will fit but turn it end over it still fits, the thing is it should only fit 1 way and by fitting it incorrectly you get gasket and bolt problems from the heat, on the broken studs well it's all been well covered by other people and all I can say is you should of asked after you snapped off the first bolt how best to go forward, they would have possibly come loose with the right application, in the end they would drill out easily I do this task often with good results, you can correct damaged holes with the Heli Coil type fix at worst, the parts listing of the manifold will show you the correct setting for it, don't get it wrong chap . best of luck tctractors. Click to expand... Thanks TC I did not realize they could go either way. The bolts that broke in the center of the manifold were about 50% rusted away near the head. They did not have much meat left. Hopefully I can figure out which way to install the new part when ever it shows up.

I decided to purchase a new die grinder kit with carbide bits for metal removal. The long reach bits were 20.00 or so for the 5 bits and the 2 die grinders with 10 shorter carbide bits were about 70.00 from Amazon. 2 days shipping included. I decided to order some new ones, just to make sure the collets were in good shape. At high speed the metal just burns right off the manifold I should be able to shape the bolt holes just right with this tool. Harbor freight sells their version for about 3 to 4 times the cost on the bits. I did a fair amount of testing with one of them it seemed like the bits would last a good while. Amazon.com: VEVOR Air Die Grinder Kit, Right Angle Grinder w/Die Grinder Combo & 10PCS Single Cut Carbide Burr Set, Lightweight, Ball Bearing Construction for Grinding, Deburring, Cutting, Polishing : Tools & Home Improvement Amazon.com: VEVOR Air Die Grinder Kit, Right Angle Grinder w/Die Grinder Combo & 10PCS Single Cut Carbide Burr Set, Lightweight, Ball Bearing Construction for Grinding, Deburring, Cutting, Polishing : Tools & Home Improvement www.amazon.com

You have to be extra careful with the long burrs. If you use too much pressure they will get a slight bend and wobble out of balance pretty bad.

For stud extraction. I used to have a fleet of 460 powered Econolines that would snap the rear exhaust manifold studs. A drill didnt fit. Also works well on LS powered full size pickup truck motors (aluminum heads).

Welder Dave said: You have to be extra careful with the long burrs. If you use too much pressure they will get a slight bend and wobble out of balance pretty bad. Click to expand... Been there and done that. If it hogs in a little it will bend instantly if strong die grinder. Simon C

Don't forget to look at a parts listing to show the correct way to fit the manifold, never think that it's the way you removed it off the engine as like lots of things in life it's been done before so check, I have to say those 6 little 3/8"bolts look to have completely beaten you, I cannot understand how you managed to knacker up the task, you are showing great skill at doing damage to your equipment,wishing you all the Best for the Year Ahead.

If can be drilled and using 90* drill head in tight spots, I use Cyclone bits to center drill first then step up. Drill till bottomed, then soak with a penetrating fluid. Then use left handed bits. I've removed many broken in 3406 heads. Never have welded any. Probably done 50 plus inframe through the years. But using homemade studs from bolts, rarely is the thread even. Personally I would buy new. And like said above the best way is in a cylinder head/guide machine that can be set up for a perfect dead center every time. Normally can use a o-ring pick to lift the start of old thread and grab with pliers and will spiral/uncoil it's self out of hole looking like a coil spring leaving original threads. JMO

Truck Shop said: If can be drilled and using 90* drill head in tight spots, I use Cyclone bits to center drill first then step up. Drill till bottomed, then soak with a penetrating fluid. Then use left handed bits. I've removed many broken in 3406 heads. Never have welded any. Probably done 50 plus inframe through the years. But using homemade studs from bolts, rarely is the thread even. Personally I would buy new. And like said above the best way is in a cylinder head/guide machine that can be set up for a perfect dead center every time. Normally can use a o-ring pick to lift the start of old thread and grab with pliers and will spiral/uncoil it's self out of hole looking like a coil spring leaving original threads. JMO Click to expand... I drilled quite a few on 3406 and 3306 with a tiny bit till through the bottom. It takes patience so the bit will not snap off in the hole from not pulling out often enough to clean the swarf out. Then I put oil down the center of the hole and let sit after I warm up with a propane torch to help the penetrating oil to get into the threads. And yes the left hand bits have pulled a lot of them out. That is my experience. Simon C

tctractors said: Don't forget to look at a parts listing to show the correct way to fit the manifold, never think that it's the way you removed it off the engine as like lots of things in life it's been done before so check, I have to say those 6 little 3/8"bolts look to have completely beaten you, I cannot understand how you managed to knacker up the task, you are showing great skill at doing damage to your equipment,wishing you all the Best for the Year Ahead. Click to expand... This has been a fun task. Thank you everyone for your suggestions. What I did learn from this is this: Once you have the manifold off and you have broken bolts, mine was 6 of 8. All 4 long bolts were broken. The Short manifold bolts dont matter as much as the long ones. If the longs ones are stuck do this. Try the welder trick. What ever does not come out then do this. Grind broken bolts flat on the head. Cut a piece of flat plate mark out your hole pattern using the old manifold as a guide. Then bolt it on head and use that as guide to insure that as you drill you are holding the hand drill at the correct angle. It is about impossible to do multiple long bolts perfect so spend your time doing that first. I think I have made a lot of progress with this and it is a done deal. Looking over my repair it will be just fine. Manufacturers make things and I can make things. There is always more than one way to make a repair. If something with this repair does not hold. It is now an easy fix. I dont have hardware that is rusted out and old. I can simply remove a nut and slide manifold right off. If my threading job fails then I will enlarge the stud hole and rethread it. I could make a solid threaded plug for that hole and then drill and tap the plug for proper size stud and or I could just make a bigger stud then turn it down on the lathe to the 3/8s dimension the manifold wants. I am not in the least bit worried about it. No damage done and it is fixed just took a little longer than I wanted. Happy new year all. May you find good health, peace and prosperity!

Tyler d4c said: Me personally id have pulled the head and sent it to the machine shop it probably needs a valve job. Make it a them problem or find another head what kind of shap is the gasket surface in Click to expand... X2

tctractors said: Don't forget to look at a parts listing to show the correct way to fit the manifold, never think that it's the way you removed it off the engine as like lots of things in life it's been done before so check, I have to say those 6 little 3/8"bolts look to have completely beaten you, I cannot understand how you managed to knacker up the task, you are showing great skill at doing damage to your equipment,wishing you all the Best for the Year Ahead. Click to expand... TC, with all seriousness, how is the correct way to remove those broken bolts. I have tried and had some success with welding, drilling, just about everything. I am currently replacing the exhaust again on my Case 580 as it keeps breaking the muffler, mounted directly on the exhaust manifold. I think I will try a short adapter first, then the muffler, hoping this takes some vibration off the bottom of the muffler. What worries me, is if the exhaust manifold ever breaks or cracks, all the bolt heads, I think they were originally 3/8 bolts with 9/16 heads, are so rusted after 35 years are unrecognizable as even bolt heads, Even getting a 1/2” socket will be impossible, more like 7/16”. In the past, I would cut the heads off flush, to get the manifold off. That would leave 2” long studs to get cherry red and float some wax or whatever and with heat changes and penetrant, might be able to get out with vice grips or a knurled socket. What is a better way? Give me some knowledge please! If really bad, I may pull head off and use my mill.

HarleyHappy said: TC, with all seriousness, how is the correct way to remove those broken bolts. I have tried and had some success with welding, drilling, just about everything. I am currently replacing the exhaust again on my Case 580 as it keeps breaking the muffler, mounted directly on the exhaust manifold. I think I will try a short adapter first, then the muffler, hoping this takes some vibration off the bottom of the muffler. What worries me, is if the exhaust manifold ever breaks or cracks, all the bolt heads, I think they were originally 3/8 bolts with 9/16 heads, are so rusted after 35 years are unrecognizable as even bolt heads, Even getting a 1/2” socket will be impossible, more like 7/16”. In the past, I would cut the heads off flush, to get the manifold off. That would leave 2” long studs to get cherry red and float some wax or whatever and with heat changes and penetrant, might be able to get out with vice grips or a knurled socket. What is a better way? Give me some knowledge please! If really bad, I may pull head off and use my mill. Click to expand... Worked with a welder together to get out some studs broke off flush. He heated the manifold around where the stud was till cherry hot and we chilled with cold water. Had a nut welded to it and after 2-3 tries they came out with penetrating oil in between. Holes had to be heli-coiled afterwards as there was not enough thread for proper engagement. I have used a carbide bit, super expensive to get oil to back side of hole, and this can help to free up. It can be pretty tough to get some out. The exhaust piece I mentioned was over$3000 from Komatsu so the 2 hours to get out was worth it. Simon C

HarleyHappy said: TC, with all seriousness, how is the correct way to remove those broken bolts. I have tried and had some success with welding, drilling, just about everything. I am currently replacing the exhaust again on my Case 580 as it keeps breaking the muffler, mounted directly on the exhaust manifold. I think I will try a short adapter first, then the muffler, hoping this takes some vibration off the bottom of the muffler. What worries me, is if the exhaust manifold ever breaks or cracks, all the bolt heads, I think they were originally 3/8 bolts with 9/16 heads, are so rusted after 35 years are unrecognizable as even bolt heads, Even getting a 1/2” socket will be impossible, more like 7/16”. In the past, I would cut the heads off flush, to get the manifold off. That would leave 2” long studs to get cherry red and float some wax or whatever and with heat changes and penetrant, might be able to get out with vice grips or a knurled socket. What is a better way? Give me some knowledge please! If really bad, I may pull head off and use my mill. Click to expand... I do lots of drilling of failed studs on engines the common size would be the 3/8" and 1/2" studs, on the 3204 engine the exhaust face of the manifold is at a slant making the task not to bad to do as the injector pump can stay in position, the requirement hear is to seal off the exhaust ports well and have a magnet of some form handy to gather up drilling's, if i can I try the washer and welding rod trick, if I cannot I just clean up the surface and center punch the flush to the head stump and take every care to drill in using a small high quality drill, the thing is every care needed for this first pilot hole and not drilling in hard until I am happy with it's position, this can be corrected without a problem by leaning the drill to go as needed, then I drill into the stud using at least 3 drill sizes to arrive at the drill that will fit in without damaging the threads in the head, then its down to picking out the stud treads with an assortment of picks and very thin nosed pliers, or just get handy with the tap set slow and steady job done, on the 3304/6 engine often the injector pump will need to be removed with the closest bolt to the timing cover needing a very long drill to reach, for this I just get a bit of thread rod long enough to the task and drill in the end of the rod about 3/4" then cut a small notch out of the side of the bar and weld the now positioned drill in place with a blob of weld, never use Stainless studs as they are nothing but trouble.