Help!! I screwed up!! Another question.....

[Telvis]

I was all ready to put my engine in this morning. I went to tighten the valve cover bolts and one oft e bolts must have been cross threaded. I accidentally broke the bolt. I tried to drill it out to use an extractor. I ended up making the situation worse. I had to weld the hole up and re-drill it. I can't get a bit to cut into it. They dull out really fast. I have went through four titanium tip bits. Anyone have any suggestions? Please tell me I don't have to remove the head and take it to the machine shop. I really want to install the engine. I am open to any suggestions. 

[dodge freak]

Is it the top or bottom?  If its the top you could rtv a gasket on both sides and try to do with out it, or right next to it drill and tap the smallest bolt you think will be strong enough to hold it. Yes this is half-ass fixes. Its harder to take the head off in the car than out and you won't know how it works for a few days. You know if you can find a bolt that might work you could do it on both sides of the busted one. You can't go the same size cause theres not enough metal but a machine screw or screws might fit and do it. Good Luck I would still use the rtv also and  I hope its not a solid cam cause if it seals I would not touch it for years. I would J B weld the old hole up.

[Telvis]

I have already welded the hole. It was small and filled quickly. I need to drill it and tap it now. I can't get a drill bit to cut. Any drill bit suggestions?

[dodge freak]

A good tool man can sharpen old drill bits up. You need a grinding wheel . If the easy out did not break which I thought it did till I rereaded the post you should be able to drill though the old bolt. Are you starting off with a tiny drill? I would use something  around .050 and go deep enough to go all the way though, then go bigger. Those tiny ones are hard to resharpen. Might just get a few brand new. Every place is close for the holiday, well not Home Depot but they don't sell .050 drills or if they do you have to buy a whole set which I am sure you don't need.

[67_Dodge_Charger]

How much time have you spent already trying to fix it?  Take it a good machine shop and you will have it done right and back to your garage in no time at all.  I have done this many times.  It is best to let the machine shop make it right.   Just my two cents.

good luck

-Robert

[71440charger]

well we do this all the time on missiles get you a counter sink bit  and use a small one to do this once you get your hole with the counter sink use a tap set to make the threads this works for us on 1 million dollar missiles so should work for you LOL  but those counter sink bits cut very well this is what they look like

[TylerCharger69]

They make reverse threaded drill bits....this is what i've used when I have broken off bolts.   I'm a bit questionable though.....how tight were you torqueing those valve covers anyway??   What I do is use the smallest drill bit possible, and move up larger diameter in small increments.  Then I use the reversed threaded bit once the hole is big enough and USUALLY it forces the shell of the bad bolt out.  If not...keep drilling bigger and bigger, and retap the thread entirely.  I had a head bolt that was busted off in a 413 once.  It was like that when I recieved the engine to assemble it.  I had to start from small and work bigger, and then reverse bit.  It takes time, but it'll save you money at the machine shop

[firefighter3931]

Been there....and it sucks ! If you can't get the bolt out, there's allways the possibility of welding on a stud in that bolt location and holding the Valvecover down with a nut & washer. I prefer studs in the heads anyway.....less chance of breaking off a bolt.

Ron

[greenpigs]

Is it one on the top or bottom?

I would try firefighters idea if it is on the top as oil control is less of an issue.

Try a cobalt drill bit...HARD stuff.

When I say cobalt I mean the material not a brand name. Try a machine shop supplier I don't deal with them so I don't have a name but a goggle should find something.

DON'T TOUCH IT TILL YOU LOOK AT ALL THE OPTIONS..IT COULD SNOWBALL QUICK!!.

good luck.

This is the first place I found but hope it helps

http://www.jamestowndistributors.com/userportal/show_product.do?pid=456&familyName=Cobalt+Drill+Bits&history=msnCobalt

[Telvis]

I put the Mopar Performance aluminum valve covers on when I built the motor last year. I could not use the stock bolts because they were too short. I bought stainless replacements that were a bit longer. When I first got them I didn't screw the bolts on all the way. I went to prepare everything for installation this morning and went to tighten the bolts down. I was using a long handle 3/8" ratchet and did't feel the resistance of the crossthreaded bolt until it snapped. I couldn't get it out with the easy out and ended up buggering up the hole. I figured I could weld it in, drill and tap it out and I would be fine. I have ruined eight 1/16" drill bits and a ton of other sizes. All are brand new and titanum coated. I even tried to put one in my dremel tool to spin it faster. I have hardly made a dent. I think i'm going to tack a stud on it in the morning. It's a lower bolt. It's the second from the left on the bottom. I think I can put a stud on it and it should be fine. If not I will take it to the machine shop down the road. What a waste of a good day!

[greenpigs]

That titanium stuff is a scam..but its your choice.

[Telvis]

I didn't have much of an option...They seemed to be the best bits available at Home Depot this morning and Walmart this afternoon. I couldn't make it to Sears before they closed. There were few to choose from.

[greenpigs]

Don't rush..pulling the head is easy how again?

I had the same deal, but my dad took care of it, now I need another head.

Order the bit and wait a few days.

[dodge freak]

You need to go to a machine shop, home depot and even Sears stuff is not as good. Look in your phone book, I have found the prices are better too cause you can buy one bit not a set, and that stuff works better. If you take it to a engine shop that is what they use not stuff from Sears. Only thing is they use a drill press, makes it much easier to drill with out it moving around.

[dodge freak]

Say I think they make something to turn a drill motor in to a press like. Maybe home depot or sears would have that, but buy all your drills from a machine shop. Once you get the first hole drill it gets better. I like that reversed drills idea sounds like a winner.

[TylerCharger69]

That's why I say...once the smallest hole is drilled.....the larger ones will be easier....just take your time not to break the bit off in the head  (yeah  that always sucks)  I have those cast black wrinkle Mopar covers, and the stock bolts were too short, but mine came with a bolt kit with longer bolts.  I always run a thread chaser through all bolt holes before I assemble an engine....that way, I know the bolts should install easily, and it helps from crossthreading

[tecmopar]

A cobalt bit or a silver/deming bit will drill through just about anything. I use cobalt bits for titainium and they work fine. I noticed you said you were going to try and use a Dremel to speed it up but thats the last thing you want to do. On hard materials you want to use a speed of about 5-600 RPM, anything faster creates a lot of heat and there goes another bit, good luck.

[TylerCharger69]

 

[Runner]

A cobalt bit or a silver/deming bit will drill through just about anything. I use cobalt bits for titainium and they work fine. I noticed you said you were going to try and use a Dremel to speed it up but thats the last thing you want to do. On hard materials you want to use a speed of about 5-600 RPM, anything faster creates a lot of heat and there goes another bit, good luck.

[Telvis]

That's may be my problem. I'm going to try to drill it again but this time spin it slowly. We will see what happens.

[BigBlockSam]

A cobalt bit or a silver/deming bit will drill through just about anything 

i've broken them too. it doesn't take much. i will only use a 1/4 ratchet on valve cover bolts. i don't know my own strength. good luck

[Telvis]

I bought three cobalt bits at Sears this morning. They barely made a dent. I used WD40 to lubricate and kept the speed down. After 2.5 hours I gave up. I'm taking the head to the machine shop tomorrow morning. So much for tgetting the motor in this weekend.
Can I reuse the head gasket? The motor has never been started. It's been sitting on an engine stand for almost a year.

[Runner]

Can I reuse the head gasket? The motor has never been started. It's been sitting on an engine stand for almost a year.

people do, but i wouldnt.  way to much work if it didnt work out.

[tecmopar]

I really hate to say this but are you sure you don't have the drill in reverse. Even with all my experience I've done this a time or 2.

[4402tuff4u]

I really hate to say this but are you sure you don't have the drill in reverse. Even with all my experience I've done this a time or 2.

I doubt it. Filler metal used in welding is very hard. Low strength yields range in the 60,000 psi area. You can go up to in areas of 110,000 psi. Who knows what electrode or type or wire he used. I think the only way it will be able to be "drilled" out will be with an abrassive type bit that will wear out the material in lieu of the cutting through the material like a regular drill bit. 

[mbyouk]

Your best bet is to take it to a machine shop and have them burn it out with an EDM. They can do it right and it won't take long. It shouldn't cost much also. The problem is that the weld has a hardness much higher than any drill can handle.

[Telvis]

It's off to the machine shop. Damn 10 cent screw!!

[Brightyellow69rtse]

i was in a machine shop for over 5 years delt with super hard stuff quite often. all i can say is carbide my brother carbide is great but it is brittle and breaks easily. it can be resharpened but you need a grinding wheel foir carbide bits or a diamond wheel. im sure a mnachine shop would sharpen them for you cheap. honestly ive seen carbide cut through some real bad stuff id try that before taking it off again......the best thing about metal is even if you screw it up you can just put it right back with a weld and try again  ........Mike