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Wesch
05-02-2008, 10:52 AM
Hi

What do you huys know or think about repairing a cracked block by stitchinh , also called metalock repair ?

Is the wall thickness of the outer wall of a 427 CI BB thick enough to do this type of repair ?

I got told that welding is nearly out of the question due to that the complete block needs to be heated up and the result is still in question.

Than again, others say that the laserwelding will do a good result also on cast iron.

I am tending to the stitching repair, but ??? [Only registered and activated users can see links]

Rgds. Günther

TimAT
05-02-2008, 03:18 PM
Where is the crack? In a cylinder wall, you can get it sleeved, no problem if it's done correctly. In the lifter valley or outside of the block might be a problem, but a good welder that's experienced welding cast iron might be able to repair it. Not sure if I'd trust it..:goodnight:

I have also heard of guys drilling a crack along it's length and inserting (driving in) small steel pins, then peening the cast over the top.

SIXFOOTER
05-02-2008, 04:14 PM
Thats pretty interesting, looks to be way labor intensive, but maybe better than trashing an otherwise good block.
Post your results if you do it.

Twin_Turbo
05-02-2008, 04:56 PM
It's also called pinning and it's very expensive to have it done.

Wesch
05-07-2008, 06:04 PM
Hi

The crack is on the outside wall, between 2 freeze plugs. It,s actually frost damage, so a piece of the wall is missing. Stitching this with a new steel insert will come about 1.200 USD + shipping to and from the place .
Just wondering about the result and if the wall thickness between the freeze plugs is sufficient to do this repair.

Welding ( except maybe for laserwelding ) is out of the question.

Rgds. GŁnther

Twin_Turbo
05-07-2008, 07:30 PM
If it's cracked there it will most likely be cracked somewhere else too. Have it mag fluxed, from the sound of it, the block is junk.

You could make a nice display out of it

For 1200 you can get a fresh core easily

TimAT
05-07-2008, 11:17 PM
I don't know about the shipping and duties involved, but a Merlin block here new is like $1900.

Cherry
05-08-2008, 03:18 AM
Bite the bullet, meaning , use it as a bottle holder behind your bar,

Hard freeze cracks run in different depths of the block, even mag flux sometimes won't show all the smallest cracks,, engineheats up and another one can and will appeare> sorry, but for the money, better off replacing it!,,,, I know your broke!!! So are we!!!

big2bird
05-08-2008, 11:51 AM
Hi

The crack is on the outside wall, between 2 freeze plugs. It,s actually frost damage, so a piece of the wall is missing. Stitching this with a new steel insert will come about 1.200 USD + shipping to and from the place .
Just wondering about the result and if the wall thickness between the freeze plugs is sufficient to do this repair.

Welding ( except maybe for laserwelding ) is out of the question.

Rgds. Günther

Gunther,
I have rebuilt between 60-80 Model T engines. Maybe 10% are cracked this way. Cast iron welding is the best, but very $$$. I have also had pinning and even silver soldering done in these areas. "If it can't be fixed, it ain't broken."
On a "rare" antique engine, you have no choice. With yours, you have one.
If this is a car you want perfect, replacement as TT suggested is best.
If you do any repair as I mentioned, it will return in 10 years or so. It's just a fact.
If you just want a go car, frankly, since it is an area that only holds 16lbs pressure, and it's only function is to contain the coolant, I would grind that area down smooth, stop drill the crack, and fashion an exterior plate from 3/16" material, drill and tap 4 holes, add sealant, and bolt it on. Very Bubba, but you can't see it, and it will hold for years. Cost? maybe $20.00 and your time. What's it worth to YOU?
Before the advent of welding, the old time racers salvaged $$ racing blocks this way, and although not pretty, it's quite functional.

BRUTAL64
05-08-2008, 08:44 PM
Gunther,
I have rebuilt between 60-80 Model T engines. Maybe 10% are cracked this way. Cast iron welding is the best, but very $$$. I have also had pinning and even silver soldering done in these areas. "If it can't be fixed, it ain't broken."
On a "rare" antique engine, you have no choice. With yours, you have one.
If this is a car you want perfect, replacement as TT suggested is best.
If you do any repair as I mentioned, it will return in 10 years or so. It's just a fact.
If you just want a go car, frankly, since it is an area that only holds 16lbs pressure, and it's only function is to contain the coolant, I would grind that area down smooth, stop drill the crack, and fashion an exterior plate from 3/16" material, drill and tap 4 holes, add sealant, and bolt it on. Very Bubba, but you can't see it, and it will hold for years. Cost? maybe $20.00 and your time. What's it worth to YOU?
Before the advent of welding, the old time racers salvaged $$ racing blocks this way, and although not pretty, it's quite functional.

Ok, you guys are not going to believe me here, but here goes. I have COLD welded cast iron blocks and heads. I used my Linclon Stick Welder (yes) and used nickel (Ni) rod. I have done head chambers and outer casting welds dozens of times. Some are still on the road today. I did this welding 25+ years ago.
:suspicious::suspicious::suspicious::suspicious:
I'm not saying do this instead of getting a good block, just stating what I did when I needed too.
Ok, this should be good. Let the doubting being.:lol:

Twin_Turbo
05-08-2008, 09:18 PM
Well, some castings hold up better than others, depends on the metallurgy. Also, a good bit of luck is involved.

Would you rely on a welded block? I would not, would you sink money into a block with frost damage? I would not. You could luck out but you also could not, if you value your money, get a replacement block and DIOADIR!

Wesch
05-10-2008, 07:04 PM
Hi guys

Thanks for all thoughts.
Nevertheless , I will most probably purchase this block and do the stitching ( metalock ) repair, which is a cold repair. The outside block wall is not structural and only holds the water, so should work out.
If it doesn't work , it costs me around 1500 USD to have a table food.

I want that block due to the numbers correct thing, don*t even want to install it into the car. Who knows what's it good for in a other decate.

If I go for it with the repair, I will let you know if it works or not.

Rgds. GŁnther

MYBAD79
05-10-2008, 10:46 PM
Any chance the crack is low enough so you can fix it with block filler ??

Twin_Turbo
05-10-2008, 10:50 PM
Be aware that the side of the block IS stressed, by the motor mount! Castings have been known to flex when using solid mounts

Wesch
05-11-2008, 02:12 PM
Hi

Block filler could be some kind of a solution for selaing the rapir in case it's leaking. I could tild the block a touch towards the repair to keep the filler there.
It should even be possibel to get to it through the freeze plug holes as the damage is exactly between 2 of them.

Motor mount ! Damn , I didn't think about that. Must have a closer look at my engine while mounted in the car to see if the damage is nearby the mount.

Here the block, if this pics shows.

It appears that the damage is on top near the head. I wonder if this will influence the head bolts . Have to have a other close look.

Rgds. Günther

Twin_Turbo
05-11-2008, 04:23 PM
They ground it all out, you can't have that stiched or they'll need to put in a new section and stich that to the rest.

Wesch
05-12-2008, 03:50 PM
Hi

Yes, unfortunately, they ground it out.
I am presently trying to locate a scrap BB to cut the missing piece out in order to stitch it in.
The stitching company wrote that they would manufacture a piece out of steel and stitch it in. I think that a original piece would be better because there are a few curves and forms here.
What do you think about the head surface. Will this influence the head mount bolts ? Looks like at least 1 of them is right at the damage ?

Rgds. GŁnther

Twin_Turbo
05-12-2008, 07:02 PM
Ye4s, the sticking will definitely warp the deck, it may to the point where you'll need to have it just touched witha surfacer, but then there go your stampings. I really think you are better off searching for another block. Can't tell what it would do for the bolt , determines if they pin straight through the bolt hole or not.

What's correct about this one? Not the serial number, so casting date and suffix are correct?

Didn't you have a viper t56 in there? It's not like you're restoring a numbers matching car right?

mrvette
05-12-2008, 09:07 PM
Bottom line....and yes, I read the thread, but my opinion is unchanged, if anything it's reinforced....


JUNK THE BLOCK

BRUTAL64
05-12-2008, 10:13 PM
Bottom line....and yes, I read the thread, but my opinion is unchanged, if anything it's reinforced....


JUNK THE BLOCK

I may have to agree here. I see to many problems that could arise from this. But, if I HAD to do it, this is a case where a COLD block weld could be the best in MHO. Good luck on this.:skeptic:

CNC BLOCKS
05-13-2008, 02:12 PM
We have the [Only registered and activated users can see links] repair kit and have repaired many cracked blocks over the years and there is a guy in MASS by the name of Frank Casey who is an artist when it comes to repairing cranks and I have seen some of his work.

Wesch
05-13-2008, 04:09 PM
Hi

I thought about it again and the risk is too big.
The stitching company could not give me a warranty that it is repairable and on the end, this block will cost me 2500 USD repaired if it works out.
If I am unlucky, it needs to be decked afterwards which adds cost to it for a non numbers matching car !!

If this was my numbers matching block, I would not hesitate and try to get it repaired, but like this.....

I want a correctly dated 321 block, but will have to wait for a better one.

Thanks fpor all thoughts , you did bring me off this idea.

GŁnther

Wesch
06-14-2008, 07:48 AM
Hi

Update.
As I said, I dropped the idea of buying this damaged block and getting it repaired.
Nevertheless,I would have been very interested to see the repair result.:(

Anyway, I found a much better deal and have purchased a correctly dated 321 standart bore block freshly honed with new guts, GM NOS steel crank, TRW forget domed pistons and 7/19 rods, all balanced.

The price is OK and on the end not more expensive as the cracked block would run to including the new guts.

Thanks again for all your support and bringing me off this repair idea.

Do you think that the present block I drive can be sold ?
It is a original 1968 Camaro 396 ci 375 HP BB bored to 427 ci, bored about 10.000 Miles ago with new guts.
Or shall I just keep it installed and drive the living shit out of it ?:D

Rgds. GŁnther

BRUTAL64
06-16-2008, 11:13 PM
Hi

Update.
As I said, I dropped the idea of buying this damaged block and getting it repaired.
Nevertheless,I would have been very interested to see the repair result.:(

Anyway, I found a much better deal and have purchased a correctly dated 321 standart bore block freshly honed with new guts, GM NOS steel crank, TRW forget domed pistons and 7/19 rods, all balanced.

The price is OK and on the end not more expensive as the cracked block would run to including the new guts.

Thanks again for all your support and bringing me off this repair idea.

Do you think that the present block I drive can be sold ?
It is a original 1968 Camaro 396 ci 375 HP BB bored to 427 ci, bored about 10.000 Miles ago with new guts.
Or shall I just keep it installed and drive the living shit out of it ?:D

Rgds. GŁnther


Interesting. I know you could bore 65-66 and early 67 BB to 4.25 but NOT 68 blocks. Do you have a true 68 block?