JB weld or epoxy or grout 8ba block

ford38v8 said:
You might install a stud, then braze up the chip around it.
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AS I was reading the posts, this is what I was thinking.
As an addendum to this thought, start with brazing a stud in place.
Then take a piece of strap steel and grind the end and edges to fit the hole,
with a rotary file or burr, shape the block until the two meet at a place so that the steel fits in as a part of the surface. Braze that around the sides, shape the outside.
And run it.

I also respect the idea of drilling the hole in the block deeper, using a water pump as a drill guide.

Karl
 
If it were me I would spay weld it. Put a carbon plug in the hole, preheat the block as best you can then spay weld. Build up what amount you think you need, then cover it to hold the heat in. May need to Helicoil the hole or just tap it. Lots of different powders to choice from, pick one you can file, so you can clean it up for a hidden repair.
 
Welding cast iron isn´t the problem, the issue is to end up with a machineable material and not having to machine the rest of the block from start.
And in this case something the OP can have sucess with without having to send out the block for more machinework then another block will cost.
So i would go with a "cold" aproach in this case and hopefully end up with little or none machine work needed caused by heatwarping.
Gaswelding, brazing or spraywelding works great but it puts a lot of heat into the piece your working on.
 
There are a 100 ways to do this. you only need one way that will work. It's not a super high stress location. My vote would be for a greased bolt, apply devcon or some other high strength epoxy and just file to shape afterwards. Drilling/tapping deeper could also add some insurance, but may not be necessary. You would just have to be conservative when tightening that one up.
I'd probably go a bit deeper if I were doing it. It depends if you are handy with drills and taps. I also might use a stud, just so there is no reason for it to be constantly wound in and out.

Mart.
 
Welding cast iron block material at a constrained joint can be almost impossible without unique furnace and cooling practices. However,the location of the needed repair here is a positive for welding. The only negative is regarding the tapped hole. I have a couple of ideas but I would want to examine the REAL piece before suggesting.

The more machinable filler is Nickle 55, if you choose a common type rod. Apply a small bead and peen like hell as quickly as possible. If you ever get the block weld area hot to your bare fingers it is a mistake. Stringer weld beads less than one inch are called for with plenty of rest time between beads. It might take a week of spare time work to do the repair and it won't be beautiful.

The interface between the applied weld bead and the cast iron can have hard spots that laugh at a high speed steel drill. Might need carbide.
 
I like post #14 Two good things the deck and pump surface's are good. I think there
is plenty of meat left there. I still would use a stud and pour epoxy right into the stud
where cracked. Next you don't have to gorilla pump bolts either. Yes can be welded
brazed sprayed but that all takes heat. I have a 1923 Ford these run hot. I go for
cigars and steam water pouring out. Pull over and the overflow tube somehow the
fan caught it and ripped it out. This tube is under the top tank. Called wife for water
and wooden matches (for kero lights) I tapped into the hole. Like a wood boat, matches
swelled leak stopped. Correctly, I took radiator out attempting to solder a new copper
tube. Nope my gun not enough heat. So I epoxied said pipe. That was 3 yrs ago and
aint leaked a drop since and these Model T typically run normaly 200 degrees or more.
Next I took the plunge for DRO's on my big Mill. No way no how to drill and tap for the
readers. Mine is a 10 by52 Cincinatti I epoxied the mounts for the readers: Four years
now and those mounts are like day one. Thought this snake stuff was a wimpy band aid. I now am a believer. Napa has a lick wood steel demo on the counter. drill it mill it
try and break it . that could work ? all I say is try it I think its cosmetic sam
 
Search the internet for "Muggyweld". I was porting a new set of GT40p heads for my 289 and struck water in several exhaust ports (ground through on one, then tapped lightly in others and broke through on them). When wife was gone for a few days, I put them in oven, preheated to 400, wheeled the acetylene torch up to the kitchen window and brazed them up using the muggyweld sticks. Got that engine pretty warm a few times doing repeated runs at the strip without any cooldown time. Never leaked a drop.
That said, in your case I think you should set that block up in your giant drill press and drill that hole deeper and rethread, then build up the areas with epoxy. Nothing more disheartening than making a pass with the welder, walking away, and 5 minutes later hearing a "ping"!
 
Maybe you could repair by grinding the area flat around the 3/8 tapped hole with die grinder and burr. Use a 3/8 x 1, or size that works, flat bar with groove filed out to match thread hole. Put two tapped holes on each side of existing thread 10x24 or 1/4x20. fasten plate. Re tap 3/8x16 hole. Epoxy the area for clean up. Might work !
 
Or you could do what cdan34 suggests, but weld in the plate and grind smooth.
Peen to look like cast iron. Less heat required doing this.
 
I watched a guy fusion weld a damaged engine block from the 19 teens. It was like standing in an oven. I was drenched with sweat just watching him. He used an oxy acetylene torch and a piece of cast iron for filler. He let it cool for near a day after completing the repair. The labor bill was high but a lot of fuel was used for the heating and cooling process. The old block was unobtainium so it was worth it to the owner for the guy to do the job.

If a guy preheated and let it cool slowly it could be brazed but it's always risky working around those thin decks. If the heat wasn't right, you could watch it crack before your very eyes.
 
I like Ronnie's suggestion in #8, considering what he says in thread #7.

I would then clean thoroughly with acetone and use JB Weld or Devcon. I have good luck with JB Weld. Make a dam around the sides with tape and use the slow set, higher strength JB Weld. File and sand, checking with a straight edge over the block surface as you go.
 
That Lab Metal stuff looks like a winner.

Try welding and if you aren't happy with the results try Lab Metal.
 
Look up belzona on the net , expensive but the best epoxy you will ever find , hard as a rock , grinds like metal but expensive , made in the U.K. , but see it on eBay all the time , they make many different ones for different applacations ,
 
Been foiling this, and I think if it's a good block, I go with the Epoxy. Clean it good and use several coats. Install a stud. Just run it. Or send it to John.
 
I think you are definitely looking at a stud ,Its a low torque error .Another idea is to clean it with a tap rotary wire brush tin it and the stud and solder it in using a Propane torch ,providing you have some thred there I think you would get all the strength you need .then fill with Devcon. to build up the surface .I shouldn't suggest this but A more Heath Robinson way is if you are not going for a Rouge award or jut around the farm would be to strap it with a 1/4 1"strap to the manifold .Were you run into problems with welding is the tension that's set up with one being hotter and shrinking pening does help but brazing is more forgiving in this regard .If you opt for this I would focus on welding /brazing the stud in for strength just down the open side then fill the cavity with plastic .Ted
 
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While i applaud people learning to weld increasingly rare engine blocks, this might be one of those times when you should epoxy.

However, if you still want to weld a block, find one that has massive damage (pan freeze cracks, rod through block spec' damage) and practice on that one. Might inspire.
 
Years ago an old Flathead mechanic used to weld up flathead blocks that were damaged.
He would set the blocks on a wood stove in his shop and start the stove up. After a while he would walk by the block and spit on it. If the spit sizzled it was hot enough to weld on.
He said winter was the preferred time of year to do this as the stove put out a LOT of heat.
 
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