Thread: valve cover bolt broke in head... best way to remove?

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ok. on my new truck 3 of the 4 valve cover bolts are broke off in the head (i have no idea how this guy did this) and i need to get them out ASAP. theyre recessed into the hole... whats the best way to get these out.
and theyre centerbolt valve covers
thanks guys
steve

a very sharp center punch and hit them on center drill and ezout

i tried that on one and it just did not want to stay centered... im thinking about drilling it out and and using some heli coils

well if it all fails you can do that. or drill them with no 7 drill and tap them but if you have to get close or you will have a mess that is why i said a very sharp puch

heli coils would work on valve covers, they dont require much torque...... sounds like the guy WAY overtightened those bolts... they only need to be hand tight

yeah man i dont know 3 out of 4 bolts?lol
oh well i had like 6 punches from 3 garages and none of em would work...

theyre just like the regular bolts for the centerbolt valvecovers

I'm like you, I've never had great results with EZ outs. I have a hard time getting the drilled hole dead center.

What I have done sometimes is to centerpunch it like Pat and the others said, but then use a very tiny drill bit to do the first hole, then move up from there. I have never used the left handed bits, but our Techs have, and like them.

By the way, the gold drill bits that Harbor Freight sells are awesome. They put sets of them on sale all the time, and I find them to be very sharp and they stay that way for a long time. It is one of the better deals at HF.


Don

a small 1/8 carbide ball mill for this and use them all the time but when the job is done they sometimes get chip up they are made for a mill not a hand drill . i have done a lot of studs and bolts and works good

They might be crossthreaded and thats why they broke.If it was just overtightened you would (should)be able to pull them out easily.If there cross threaded they aint coming out until you drill them out.

Years ago I learned the proper way to drill out rivets in aircraft skin ensuring that I didn't have to go oversize. It's all about finesse using the drill, with the drill rotating slowly, move the drill to keep it centered until you have an established drill start. If you attempt to apply full power to the drill with out finesse, then yes, it is easy to lose your center and the drill bit will wander possibly taking out some threads. I have found that by exercising extreme care, using the drill at slow speeds and finessing it you can keep the drill on center and drill a hole straight through the middle. Use a pilot drill first, if drilling out a 3/16ths bolt I would use a #30 drill. If the easy out doesn't work for you take the hole out right up to the ID of the hole and pick out the remaining pieces with a dental pick and run a bottoming tap back through the hole when done.

left hand drill bits work great for me.... i bought a set of them from the cornwell guy in titanium for $58.... and i've already used them quite a bit...

yeah my boss is lettin me borrow his left handed bits tommorow i think

Sears sells them in a kit. I don't recall the price but they work real well.