I just got a 239 to rebuild and the PO broke about a dozen bolts off in it. I know I could try use an easyout but I just tried heating them up with a torch this weekend and they wouldn't budge. If I drilled them out and cleaned it up with a tap, would it hurt anything. I do this kind of stuff to aircraft at work but we can't use a tap on those threads because they're rolled threads. I'm very tempted to just drill them out but I wanted some advice before I started. Also, he tried to drill one of them out himself and messed up the threads a little. What kind of insert would you recommend for that? Thanks.

 

If you have any bolts that are broke off even with the surface of the block one technique I have heard used that is suppose to work almost every time is to lay a flat washer over the broken bolt and then top that with a nut. TIG or MIG weld the inside of the nut to the broken bolt, let cool a little and then turn the piece out. If it breaks off do it again. The idea is the weld will heat and expand the broke stud when it cools it should break free and turn, again, if it doesn't work the first time do it again.

As for using easy outs, I would never use them. It's too easy to break an easy out inside the hole and then you'll have a real mess. If nothing else I would drill the broken bolts out using a high quality small drill and plenty of oil, working up to a larger drill until you have the correct size to retap the hole with a high quality tap, and plenty of tapping oil. If the threads aren't too messed up just leave them, if they're really bad I can't see why you couldn't use a heli-coil to fix them.

 

Thanks. I'll give the welding thing a try. I thought a helicoil would do it but I wasn't sure. I'm taking it to a place here in town that can hot bath it and get the corrosion out of the water jackets but I want to get this done before taking it there.

 

Have you tired taking them out once they cooled down? Most make a mistake and try to take out stuck bolts when there still hot.

 

It can also be done with a stick welder,no real need to weld inside nut

 

I've done the mig thing on my block. Three times. Each time the stud broke off shorter, it started out 1/4" above the block, then flush, now it's about 1/8" below the top deck. Mine was the bolt in the stud pocket below (above??) the hole in the water jacket, with the Ford Number cracks, so I'm sure it's been rusted for a long time. Didn't work for me, but I'm sure it would have for any of the other studs, had they broken off.

Ray - I don't understand about not welding inside the nut. There's no other way to do it, at least what Bob and I are talking about.

Not sure how I'll get mine out of the block, now - probably take it to the machine shop I use. Will cost me about $50, but they do good work, and it's worth it, to save a block...

R

 

Roger,

What happend to your engine? It was together, ready to install when I was by you, wasn't it?

 

I've been successfull with the welding the nut to the end of the broken stud a few times. I swear by 3 in 1 oil and letting it SOAK for several days, it sure seems to help. I've also been lucky in the progression of drill bits to a larger diameter and then finally a counter clock wise bit that turns out the remainder of stud. Removal of broken studs is a test of patience, time and luck.

 

One method I have used is to apply penetrating oil to the broken off bolt, and let it sit. go back the next day, and hit the top of the broken bolt with a hammer, not hard, but not too soft. Between the penetrating oil, and the vibration, and the impact, sometimes the rust loosens up a little. Grab the bolt with a pair of vice grips, and turn the bolt out.

 

if the bolt is broke off short enough to have to use a washer all that is necessary is just weld nut on to have somethng to turn it with
if the boltis broke of high enough to come have way through a nut no washer is necesary
if too much heat is used filling the nut the bolt will crystalize and break off below the weld
always let bolt cool some before trying to remove it and a good bath with PB Blaster while hot does wonders

 

Bob, you know me...always have to break SOMEthing! Nah, it's my spare block, the one that came with the truck. the other motor is rebuilt, runs just fine and dandy...

Truer words were never spoken! I have been using Kroil, and those two bolts in the block, are the only two I've had any problem with whatsoever.

Ok, I see. I put a washer on every one, just to align everything, and keep from hitting the block. don't care if it will hurt it or not, just something I do. I don't "fill" the nut, just enough to make sure I have a good weld. And I do know that tig works better than mig, if you are lucky enough to have a tig.

R

 

I was torquing a head bolt and I noticed that the torque was staying the same as I turned the wrench. I was only about 5 lbs to my torque. I decided to stop and pull the bolt out. When I did, I noticed that several of the threads had streached almost to the breaking point. Lucky for me I pulled the bolt out before it broke. A quick run tto the store for another grade 8 bolt and I was back in action.

John
NNY

 

On trick I was taught and that has helped me remove amny stuck bolts and nuts is to heat up the thread area to near cherry red and then rub paraffin wax (canning wax) over the threads. With the heat the wax penetrates deep and quite often the bolts/nuts come out with minimal effort. The only problem with this technique is that the hot metal tends to vaporize some of the wax and has the potential for small flash fires, so I keep a wet rag handy to put out flames. It does work though