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

The cheap E bay special turned out to be an ITR manifold from china. As far as I can tell it looks good. The gaskets I ended up with I am not so sure about. I bought 2. They look like a thin piece of aluminum. Is this type of gasket any good?

With both surfaces being flat and properly torqued the gasket will work.

All the itr stuff i have got was good hasnt been alot tho

I get a good amount of heads and manifolds sent to me with broken studs. 8 times out of 10 they come complete with broken drill or ezi out. That's good because the job takes a lot longer. Depending on the circumstance it will go on the mill and I use a carbide end mill. I can usually get the stud out without damaging the thread. Drills are prone to wandering off centre so don't use them much. I sometimes spark erode them out which does a good job but is slow. If you can weld a nut or washer to the stud that often works but use a MIG,not stick. A bit of patience working the nut back and fort will do the trick. We did have a bloke bring us a Scania head. He had been trying to get it out for 5 days . Broken off the exi out and generally made a mess of it. His boss was about to sack him because the truck had a schedule to keep. It took us 1 1/2 hours and charged him 150 bucks. You would have thought we had stolen his missus. Spread a story around about how expensive we were and how we ripped him off. I should have charged him double and it would have still been cheap.

I seem to remember the cat gaskets being like that

RayF said: I get a good amount of heads and manifolds sent to me with broken studs. 8 times out of 10 they come complete with broken drill or ezi out. That's good because the job takes a lot longer. Depending on the circumstance it will go on the mill and I use a carbide end mill. I can usually get the stud out without damaging the thread. Drills are prone to wandering off centre so don't use them much. I sometimes spark erode them out which does a good job but is slow. If you can weld a nut or washer to the stud that often works but use a MIG,not stick. A bit of patience working the nut back and fort will do the trick. We did have a bloke bring us a Scania head. He had been trying to get it out for 5 days . Broken off the exi out and generally made a mess of it. His boss was about to sack him because the truck had a schedule to keep. It took us 1 1/2 hours and charged him 150 bucks. You would have thought we had stolen his missus. Spread a story around about how expensive we were and how we ripped him off. I should have charged him double and it would have still been cheap. Click to expand... Why not stick welding? They even make special rod's for studs broken in the hole that the flux prevents welding the threads. I can see Mig for getting the arc right where you want it or for non experienced welders.

I guess I must be inexperienced because MiG seems much easier and because I can keep the gun on it much longer, the heat transfer is a lot better. I have used some of the specialty rods and some 308L rods and much prefer stick, if its a large bolt but usually it’s under 1/2” and the MiG works better for me.

HarleyHappy said: I guess I must be inexperienced because MiG seems much easier and because I can keep the gun on it much longer, the heat transfer is a lot better. I have used some of the specialty rods and some 308L rods and much prefer stick, if its a large bolt but usually it’s under 1/2” and the MiG works better for me. Click to expand... Best to use high alloy or super strength rod as Stainless is very hard to drill out if welding does not work. Welder Dave said: Why not stick welding? They even make special rod's for studs broken in the hole that the flux prevents welding the threads. I can see Mig for getting the arc right where you want it or for non experienced welders. Click to expand... Agree with Dave and I have some of the rod that the flux protects the thread and I have tried couple times and was good. Just my experience. Simon C

The stick rod I showed above is the one that coats the threads with the slag. Anyone say use a mig has never used those Esab rods. Weld til it quits (3/4 of a second), watch the slag pop off (less than 2 seconds), weld again, lather, rinse, repeat, until the weld is proud of the hole. Then 7018 a nut on, allow to cool briefly, then wrench out the stud.

Some days your accomplishments are great. Today my accomplishments were measured by 3/8 x 16 broken studs on the riser. I went with the 7018 again and welded on a nut. I actually prefer the nylon lock nuts with the nylon on the bottom as it melts nothing sticks under it. After welding on the nuts I heated the stud and part cherry red with a torch then cooled the stud with wd 40. You could see it go in after the temperature got to the point that it would not catch on fire. Used the vise grips in a back and forth action just enough pressure that it was close snapping. Both came loose. Hurrah. Then cleaned up the treads with a bottoming tap.. good to go.

Georgia Iron said: Some days your accomplishments are great. Today my accomplishments were measured by 3/8 x 16 broken studs on the riser. I went with the 7018 again and welded on a nut. I actually prefer the nylon lock nuts with the nylon on the bottom as it melts nothing sticks under it. After welding on the nuts I heated the stud and part cherry red with a torch then cooled the stud with wd 40. You could see it go in after the temperature got to the point that it would not catch on fire. Used the vise grips in a back and forth action just enough pressure that it was close snapping. Both came loose. Hurrah. View attachment 354043 View attachment 354044 View attachment 354046 View attachment 354047 Then cleaned up the treads with a bottoming tap.. good to go. Click to expand... Good job. After I weld the nut on I heat the outside of the casting to close to cherry and that often helps to remove welded stud. Simon C

Georgia Iron said: View attachment 353976 View attachment 353977 The cheap E bay special turned out to be an ITR manifold from china. As far as I can tell it looks good. The gaskets I ended up with I am not so sure about. I bought 2. They look like a thin piece of aluminum. Is this type of gasket any good? View attachment 353982 View attachment 353983 Click to expand... Lovely pictures of your Thumb, how about a picture of the manifold showing the Turbo mounting face so if you want I can tell you the correct way to fit the manifold to the cylinder head.

tctractors said: Lovely pictures of your Thumb, how about a picture of the manifold showing the Turbo mounting face so if you want I can tell you the correct way to fit the manifold to the cylinder head. Click to expand... Taking a guess here but is the same as in the photos with the top being the same orientation?

Upon a closer look i see this ITR manifold is garbage. The old one was nice and smooth . This is a second rate trash casting. Going to try and smooth up the the inside The slag left in this looks like it would come off down the road and destroy the turbo. SOB. The last photo is the old nice and smooth.

My little die grinder and long reach bit cleaned it right up. Still not as smooth as the original but not so much so that i will loose sleep over it.

Since their is so much talk about removing studs we used to have pretty good success with parrot beak channel locks. Holding pressure on channel locks and tapping end of stud with a hammer

Well it sildes right on easy and it 100% in alignment. This little die grinder ate that cast like it was nothing, as a matter of fact it was scary how fast it worked on high speed. I opened the lower side holes just a little to allow for my poorly centered studs and it did the trick. Very valuable tools this is. Original tolerance above. Opened up slighty above. Master of the universe. You can see all the grindings and casting slag, i burned out above the tool.

HarleyHappy said: I guess I must be inexperienced because MiG seems much easier and because I can keep the gun on it much longer, the heat transfer is a lot better. I have used some of the specialty rods and some 308L rods and much prefer stick, if its a large bolt but usually it’s under 1/2” and the MiG works better for me. Click to expand... Mig is nice for smaller bolts. Stick typically has better penetration (hotter) at the start but can be difficult on a very small area.

Got it all back together and started back up. I went down to Cat and sat down with a salesman and looked over the information he had including the TMs and service manual. I could not find any information on which direction the manifold is supposed to go. Cat did update the small bolts on the outside mounting holes. Maybe 3/8s x 1". Guess how much they are each. $23.00 per bolt. I used 20 grade 8 bolts and made my own studs. I used lock washers on the outside mounting bolts and the lock tabs on the 4 inside bolts. I am not sure if the lock washer is a good idea or not. Cat uses the locking tabs and thats it. I also used galvanized nuts which dont seem to have as good or as strong of thread as the harder grade 8 nuts do. They seemed to stretch a little more. I am going to run it awhile and check the hardware for issues. I would imagine that you could spend close to $200.00 just for the Cat hardware. Hopefully I dont need to buy twice and cry twice.... On the warm up run no leaking was noticed. Online some guys say these nord lock washers are the best bet. I might go ahead and order some and swap them out. Bolt Depot - Nord-Lock® washers, Delta protekt® plated steel, 3/8" boltdepot.com

Nord-Locks don't come loose but can be hard to remove. They make an extreme Nord-Lock too that's even better. I don't know if they're good to use when heat is involved. Not sure about grade 8 bolts either. They tend to snap instead of deform.