I removed 12 bolts on right side of block no problem (I'm trying to replace the head gasket). was having trouble with 2 so I tried an impact wrench..big mistake I guess... even on mid range torque setting it did'nt loosen anything at first then I one let loose. I went onto another one and it let loose too. I decided to hand remove the loosened 2 I just did. To my horror, they are snapped off 2 inches down. Now I am scared and need some advice before I make a bad situation worse.

 

Is this a flat V8? Are you saying they are broken off down below the deck of the block? Which bolts are they, the ones that are in the center? Whatever you do, do not use an Easy-out!

 

Yes, it is my 239 flathead v8, one bolt is broke to the right of the temp sensor on the top of the block, the other snapped one is straight below that one( on the bottom row of bolts on the head). I will not use easy out like you said, I just don't know what to do, other than I AM NOT trying to remove the other stubborn bolts at this point.

 

After soaking the snapped bolts with kroil, what tool should I try to remove the bolts with that are snapped off at the bottom of the treaded holes in the block?

 

My machinist told me there is a welding rod that you can weld down in the hole and use it to screw out the bolt. He said the heat from welding will usually free it up easy. If you want, I will ask him about it and the procedure to use it. Don't do anything to mess up your block. He is an industrial machinist and said they have used this at work. Check with your local welder supplier and they may also know. Good luck.

 

I have almost no flathead experience but this will bump your message to the top and a real person will come along.

The welding rod could work, especially the heat.

In the interim do you think that the head bolts are broken off below the block surface (deck) if the head was not there? If so your toast, …….its machine shop time I’m afraid. If the bolt was sticking up past the block surface if the head was off there is some hope.

The big IF of course is getting the head off without breaking more bolts, I don’t know (because I don’t) if flathead head bolts go into the water jacket which might be part of the problem if they are rusted and sized in the block. Is this just on one side so far, right? Is the coolant rusty? Heat is the solution (usually) to anything sized so this what I would do if nobody come up with a better idea, reinstall the good head bolts, fill with clean water and if rusty the best rad flush chemical you can buy (use lots)because you are going to be dumping it anyway or lots of that rust chemical for cleaning sinks/tubs and start the truck with the rad covered and run it as long as you can until it almost boils (heating the block), shut it off, and try loosening the other head bolts.
If you get the head off and the broken ones are sticking up, weld the stud or heat the block someway around the bolt/stud and using stud removing tool (rental) or if you think it might move, a pipe wrench.

 

The two bolts that broke are "wet" bolts, not the only ones.

If the bolts are broken off flush with the block (real common), and you are a skilled welder, the best trick IMO is to put a nut over the hole, and run a bead with a MIG to weld the nut to the remains (fill the nut). The heat will usually break the threads free, and you can turn the nut to remove the remains. There are other machine shop methods, but expensive and usually only done when the block is already fully machined (like EDM machining out the remains).

Most reliable way to remove the other bolts is to hand TIGHTEN them a little, then hit them with an impact to loosen. Since yours seem to be in a bad way, I'd be tempted to say you should hit the heads with a hammer blow first. Not too hard, but not wimpy either. You don't want to just pull smoothly on a breaker bar to loosen; hitting the end of the breaker with the palm of your hand has worked best for me.

 

Thanks for the helpful tips. i am not a welder by any means at all.
The best thing I can do at this point is to retighten the bolts I have loosened already, fill/top off the radiator with fluid and take it to a shop to have this issue fixed.
I pray that they can get the snapped off bolts removed without pulling the whole engine.
I noticed that the bolts are different lengths, on the top-snapped one (by the temp sensor) the bolt is very long...the unthreaded shaft is twice as long as the unthreaded shaft on the bolt that snapped along the bottom of the block.

The good news I guess IS that the breaks have occurred right where the threads have started on the bolts. That tells me that with the head removed the threads should be level with the block at least. Someone could use the weld/nut approach hopefully.

What makes me sick is that I tried the tighten first with the impact wrench approach and these bolts still broke. I snapped off the bolt that holds down the distributer (back a few years ago when I tried to adjust the distributer). Wound up helicoiling that by the time it was all said and done.
This flatheads bolts must be in rough shape. I'm afraid to repair/replace any kind of gasket on it at this point.

 

Most almost 60 year olds are, ....................including this one.

 

I think that you'll end up with the engine out, both for repairs to the snapped bolts and to chase the threads in all the holes. You'll end up with all new gaskets and maybe address a few other problems. Look at it as insurance against problems down the road.

If you do decide to drive it to the shop, which is risky, leave the radiator cap off to keep pressure off the gasket.

It's probably possible for a mechanic/welder to lean over the fenders to get at them.

Note you should HAND tighten a small amount first, then loosen. I would put the impact away on this engine!

 

Albuq F-1's advice is spot on. My experience with flatties and working on old junk in general tells me that in a situation like yours, they'll break if they're gonna break and there's not a whole lot you can do about it. Once the first one snaps, there's no longer any point in freaking out and worrying about breaking another. Whack them with a hammer and them try to pop or jar them loose, but don't be surprised if you snap some more. The head has got to come off one way or the other. At this point, I personally would have the engine out on a stand. Getting the remains of the broken bolts out is not something that you'll be wanting you or anybody else doing over the fender of that purty truck. Much less chance of damage to the paint and you'll be able to do a better quality repair when it's horizontal in front of your belly and not at a 60* angle down in a hole. I've had good success with welding a nut to the remains and getting them to spin out. If that doesn't work, you're left with drilling them. That's not something that you want to be doing if you're not experienced. It's a good way to go from needing a few broken bolts removed to needing a new block in short order.

It could always be worse. At least yours broke at the surface of the block. The last flatty I tore down had the shank of the bolts rusted into the head. On those bolts, the heads broke off and there was no way that the head would slide over the remains of the bolts. I ended up removing one head from that engine with a sledghammer in little tiny pieces.