[MescaBug]

I have a '73 455 block that is cracked. Previous owner told me he did know and had this 455 in a T/A for a few years without any issue. He's a good friend of mine and I trust him. They magnafluxed it, and the crack was epoxied.

I used a generic picture to pinpoint the exact location of the crack. Crank side, near #8 cylinder. Its about 3/4" long, not sure how deep.

The shop told me they can 'pin' the block.. Not sure what he is talking about. What are my options here? Is it fixable?

Dont tell me to get another block. 455 might be quite common in the States but here in Canada, we dont see them often.

Any advices would be greatly appreciated.
Thanks
Dave

[frankyboy455]

???

[johnta1]

Is the crack from the bolt hole/boss?

Don't think there would be any water there?
(if pic is marked right)

Also wouldn't think there would be much stress there except the bolt/bolt hole.
(does pump stay bolted tight?)

Why are you worrying about it?

Any problems with it?

[steve25]

Why is that first block picture from a magazine,and what is that block as it has much more closed off webbing in the lifter valley?
Pinning in that area is perfectly fine as long as the shop does first find the end of each crack and drill it out to start the pinning work.

[MescaBug]

Originally Posted by steve25

Why is that first block picture from a magazine,and what is that block as it has much more closed off webbing in the lifter valley?
Pinning in that area is perfectly fine as long as the shop does first find the end of each crack and drill it out to start the pinning work.

Like I said in my post, this is a generic picture from the HPP mag to pinpoint the crack. The block is at the shop. Cant take a picture right now. 2nd pic is the actual block removed from my buddy's T/A. Still dripping oil.

The crack doesnt come from a bolt hole. Its on a flat area, below the deck surface. Hard to explain without a good picture... Guys at the shop are confident that pinning should do the trick. I just want to know what you guys think.

That block runned fine with the epoxy patch over the crack.

[johnta1]

Pin it and don't worry.

[Ragtop Man]

Shop guys see worse all the time. Were there any problems from the crack? Doesn't look like its migrating from a bolt hole to oil or water, or in the valley or on a web where it could get to be a real problem. Pin it then forget it.

[steve25]

If there is any uncertanity that the crack many go into a water jacket than also place a good layer of JB weld over the pinned area and when your first fire the motor over for the first time, have just water in it with some block sealer just in case!
The other thing to note is I would now not trust the block to hang in there very long at more than 600 HP, or with more than a 4.210" stroke at over 6500 rpm.
The stress load a block see`s in the main webb area are times 4 for every 2000 rpm increase!

[Cliff R]

For a crack on the inside of the block that goes into a water jacket, you also have the option of filling the block above the crack after the repair is done.

I still don't like using blocks cracked into water jackets where the leak comes out into the lube oil. Just too many things can go wrong with those deals, and considering the amount of time/funds put into a 455 engine build, it's still risky using a block with a crack in it.......Cliff

[Ragtop Man]

One idea to try out on the rest of the builders in the forum:

If the crack is that low in the block, and the lower area of the water jackets are basically dead space that is home for sediment and other shizzzzz, why not do a partial block fill to the bottoms of the freeze plugs? Would pretty much make any lower end hairline problem irrelevant.

Assuming all of this is done after a proper pressure test.

[Half-Inch Stud]

Originally Posted by johnta1

Pin it and don't worry.

I was going to say " let it ride" but pin-it per above may relieve any residual stress propagation....that has not propagated.....yet.

[Formulabruce]

I prefer to grind a shallow "V" in the crack and Nickel weld it, after warming it, of course. But I have also ground a shallow "V" and used "Marine tex" on the inside of blocks just like this with excellent results. Pin can relieve stress, but that crack isnt a typical stress crack, IMHO.
Evans coolant will eliminate any corrosion in the water jacket too..

[Cliff R]

I've welded on a number of these blocks over the years. In heavy areas it's always a 100 percent success. In thin areas associated with water jackets there are some blocks that just woln't weld without the crack spreading no matter what you do for preparation. Others weld just fine just like you are welding on a flat piece of plate steel.

I have always suspected that the base material isn't exactly the same thru all the years of production, as some blocks weld just fine and others don't, using the same procedure(s).....Cliff

[Formulabruce]

Originally Posted by Cliff R

I've welded on a number of these blocks over the years. In heavy areas it's always a 100 percent success. In thin areas associated with water jackets there are some blocks that just woln't weld without the crack spreading no matter what you do for preparation. Others weld just fine just like you are welding on a flat piece of plate steel.

I have always suspected that the base material isn't exactly the same thru all the years of production, as some blocks weld just fine and others don't, using the same procedure(s).....Cliff

That has to be true, be nice to see a nickel content for each year wouldnt it?

[MescaBug]

Thanks for the comments. Just got a call from the shop; 400$ to pin the block and they cant garantee the job...

I will never feel safe knowing that the block I just put $$$$ is not 100% structurally sound.

Cranks and rods are good. So I'll get another block. Period.

[Formulabruce]

what are you going to use this engine for? I would be totally comfortable with grinding that crack some and using Marine tex in that crack.. I have used Marine tex on blocks that went right into service in 30 minutes..( outside repairs) Wasn't this block you have in service with the crack??

[MescaBug]

Standard street rebuilt. TRW forgings, 2801 cam. Nothing fancy.

And yes, that block was in service in both a T/A for 2 years, and in my GTO for a few months. Never had any problems. As I said, the crack was covered in epoxy.

If the crack is not deep, I guess grinding it and filling with Marine Tex or epoxy might work.

[gtofreek]

We weld cast iron with the tig welder and cast iron rod. Here are some pics of a block we welded the ear back on after it was completely broken off. Can't even tell it was fixed when done, except for the welding you can see on the bell housing surface after it was resurfaced.

We even have a trick for adding in the texture of a cast finish as you can see in the final pic.

[uforacing]

Originally Posted by gtofreek

We weld cast iron with the tig welder and cast iron rod. Here are some pics of a block we welded the ear back on after it was completely broken off. Can't even tell it was fixed when done, except for the welding you can see on the bell housing surface after it was resurfaced.

We even have a trick for adding in the texture of a cast finish as you can see in the final pic.

Very nice work. Nice to see that the detail freaks are not dead.

[gtofreek]

When we repair stuff like this, it is important to us that it looks as if it were never damaged in the first place.