Imagine a long string of curse words here. I've worked all day just to get 4 bolts off the turbo down pipes going into each exhaust manifold. No way to get the turbo out otherwise. Enough Blaster to drown a horse. No sockets thin enough to fit on the nuts. Wrenches only round them off. After two hours, I gave up. Figured I'd have to cut them off, so I hit the dealer for new bolts - 2 more hours and $65 for 4 bolts and nuts.

Using a grinder, sawzall, chisels and hammer, 4 hours later I get the pipes off. But, each bolt is still in the exhaust manifold. A couple are ground off flush, one is sawed off flush, and the last one broke off a half inch above the manifold flange. None will come out. Went and bought the hardest drill bits Home Depot carries. I drilled on one for 10 minutes and you can barely tell.

I don't think it will matter even if I drilled all the way through - the bolts are like part of the manifold now. Beating with a punch and hammer does nothing. It must be a Minnesota thing (where the bus came from) how rusted they are. Never seen anything like this down here.

No way I can take the manifolds off - those bolts look just as bad. What am I doing wrong? I'm thinking the engine has to be pulled just to get these four bolts out. I heated with a small propane torch for about 3-4 minutes - do I need a hotter torch? This is insane. Is my drill not going fast enough? Do I need to start with a tiny drill and work my way up? Geezus, that would take hours.

I'm so screwed. Turbo is a two hour job on Fseries.

 

Got a welder....it might be time to weld. A nut to them.

 

Actually, I'm finding Liquid Wrench is better than PB Blaster lately. And HD drill bits are not that great.

Considering your situation, I would clean off the PB Blaster with some brake or carb cleaner, put some Naval Jelly on the two sides of the manifold ears overnight, and hope it can dissolve some of the rust jammed between the bolt shanks and manifold. If you hammer too hard on those manifold ears, they can break.

 

They aren't threaded in. And now there's nothing left to weld to on a couple - ground off smooth with the flange. The nut and bolt both had shoulders. Now I can see the round circle of the bolt, no shoulder left. I assumed it would punch out.

I must need a different drill bit. Watching YouTubes and guys are able to drill them. The bits I bought said Hard Metal on them, but they're not drilling like the guys I'm watching.

 

You're not going in reverse, are you?

I know they are not threaded in, which is why a stated shank. But they are jammed due to the rust crystals expanding and taking up all the clearance.

 

Yes, your first reply didn't show before I posted to Smoedog about there not being threads. Not drilling in reverse and too late for naval jelly tonight.

I gotta be doing something wrong with this drill - those YouTube guys are having no problem, and I've drilled out bolts before. I either have bad bits or I'm not applying enough force to the drill - it barely fits in the space. and can't get my hand behind it - or it's not going fast enough - it's cordless and I'm letting the batteries charge up.

Do you know what kind of bits would be best? IIRC, these were titanium.

 

OK, now I know that it's better to drill slow, so I'm good there. And I the bits I bought are cobalt - arrrgh - not sure why they're not penetrating this bolt like the guys on YouTube. Says they have a "quad-edge tip," would that matter? I bought a 3/16" and another larger size, neither was digging in like I expect. All I can think is that I'm not pushing down hard enough, and maybe I need to slow it down.

 

After long drill and not going through, the metal maybe work harden. You can try smaller bit first. Such as carbide tip ceramic bit. Use plenty of coolant fluid. Or diamond coated bit and dremel.

 

Bad mood last night.

Retail bits from Bosch or Dewalt are not as bad as others, and there are different grades of Cobalt. I've got some industrial-grade bits from commercial sources that are excellent and very expensive. I've got a Craftsman bit set from 40 years ago that still has mostly original bits (resharpened); they don't make them like they used to. But the description you mentioned sounds like it's the Milwaukee bit, which is better of them. You might want to look carefully at the tip and see if you have chipped it so that it won't cut well. Those bit tips only last during the factory sharpening with me. You might be going too fast.

As namnguye mentioned, the metal may be heat or aged hardened, work-hardened if they have stretched past yield buy a guy with excessive force. Or someone installed 12.9 bolts instead of 10.9 or maybe stainless. But it's perplexing as I never encountered having this much trouble drilling a broken bolt as you do. Your other problem is drift with a bolt that hard and especially hand drilling. The cast manifold will be softer than the broken bolt, especially yours, so the drill will pull into the softer metal if there is an edge breakout. An EDM machine would be the best course, but you will not pay for a guy to come out with a portable unit.

All of this is why I suggested a try at dissolving the rust around the bolt's shank. Unless ToolManRob has other suggestions.

 

OK, now I know not to push down too hard. And I finally found a bit that drilled - a small 1/8" Milwaukee cobalt with a "split tip" rather than the quad tip. The smallest sizes have the split tip. It drilled pretty good for about a half inch, long shavings rising out of the hole, then it kinda quit. I was trying not to push on it, so maybe that's just as long as that bit lasts. Guess I gotta buy a dozen or so. I've tried moving up to the larger quad tip sizes I bought yesterday after getting that starter hole - but not much. Also bought a 7/32 split tip today, but it doesn't drill like the little one.

Net result, the 1/8 bit is almost through the flange and out the other side (I cut the bolt head off over there), and a larger hole, prolly 80% of the bolt diameter, follows it about half way. Still, what's left won't budge using the hammer and punch. $^#&*%&#(

Also tried heating it up again - nothing. What are the chances I can burn the rest of the bolt out with the torch? I've been only heating the flange. avoiding as possible getting the bolt in direct flame.

Not sure where to find any better bits, and prolly can't until Tuesday anyway. So I'm going to try one of the cobalt bits from OReilly's next, forget the brand. If it's no better than the Milwaukee, I'll go back to those - prolly cheaper at HD.

Sorry, Jack, and never got the naval jelly, or the acetone Mark recommended. Been continuing to soak with PBB, for what it's worth. Just got focused on drilling. My drills don't have a trigger lock. %_#%_#&. If a new bit works as well as that last one, I should punch through the bottom side pretty quick. But, I get the feeling that's not going to free up the rest of the bolt. It really acts like one hunk of iron, not two pieces rusted together. I'll prolly have to, somehow, drill out the complete diameter.

 

You should always start with smaller bits. The point feeds better. I'd stay with Milwaukee. Considering you've rounded the bolts and have trouble drilling, the possibility of someone putting a poorer grade of stainless is more probable.

You are not going to burn the bolt out; an EDM would do that. Earlier this year, on the bulldozer, I played with PBB, A/TF, and LqW. The LqW, despite it being an older in-service product worked best, took less torque after all were soaking for 3 days.

I'm guessing Mark as suggesting acetone to work with ATF; since it's not in the thread, I guess you guys are talking privately rather than on the board.

 

Mark responded to my post on PS.org. I'm not sure much can be done for me. The bolts look stock, and no reason to think not - this bus doesn't show signs of being worked on much and it only had 80k miles when I got it.

That Milwaukee bit was definitely worn out. The O'Reilly bit broke right through the last of the bolt depth, but then, it didn't make much progress on the next bolt. I was thinking that me grinding on the bolt head created the heat to "harden" the metal; but I didn't grind the next bolt I'm trying - I cut it off with the sawzall - and it seems just as hard to drill (with the OR bit), and just as stuck - punch and hammer do nothing.

I'm going to try once more with new Milwaukee bits. A small one to start on that next bolt, and a larger one to try to ream out the first one. If I can't ream the first one, not much left I can do except pull the manifolds. The chances of that being successful are slim to none, likely just more broken bolts.

Question: why can the sawzall cut the bolts but the drill can't drill them?

Crazy to junk a perfectly good bus over 4 lousy bolts, but I may have no choice. I expect a tech will charge me more to remove those bolts than I paid for the bus.

 

Well guys, here's the plan. For any newbies to the forum who stumble onto this thread, don't do this.

I can't get those bolts out. I'd have to either pull the manifolds with the high risk of breaking more bolts, or have it towed to a shop and pay them some huge money.

I only paid $2500 for the bus and I made most of that back carrying loads back to Tx from picking it up in Minn. I've put 20k revenue-generating miles on it since then. It was a free bus and has paid off great since then.

So, I'm going to take a chance. Talked to my gasser-tech buddy and he suggested burning the bolts out with the torch. I know Jack said that requires and EDM (what is an EDM?), and he's almost always right, but what the hell, I'll try.

Probably doesn't work, so Plan B is to just weld the pipes back together. Not quite sure if I can pull them tight enough together to seal up, but I'll try. Then just drive it until I need to take those pipes off again. Maybe I can just tack it so that I can grind the weld off to pull the pipes if I ever need to. If not, I'll just junk it.

If neither option works, I can junk it now and not feel bad.

The Life of Bonehead is not for the squeamish.

 

I would just drill it out. You can try carbide tip bit. I am almost 100% sure it'll go through. Most of your problem is probably heat while you drilled it. Did you put a lot of coolant on it when drilling? Even water works. Drill a little, take out, clean up the hole, and repeat.

Try these, they're dirt cheap.

Make sure to keep it cool when drilling or it'll break off.

https://www.harborfreight.com/carbid...-pc-61617.html

 

LOL, Plan B it is. Might have helped if this torch I borrowed had one of those levers that blow extra gas to clear out the holes. Without that, the molten iron just filled up the hole. Oh well.