Cracked Block - How bad is too bad?
 

So, the original block to the 68 Mustang has two cylinders with cracks in them. One is really bad, and the other isn't as bad, but they're both bad. I think that made sense... [img]<<GRAEMLIN_URL>>/hmmm.gif[/img] I'm unfamiliar with repairing engines as far as how bad a crack can be before the block is deemed unblockable [img]<<GRAEMLIN_URL>>/biggthumpup.gif[/img] I'll post up some pics later, but after talking with a few guys, seems almost anything short of missing pieces can be fixed. Is this true or not true? Being the original block, I'd love to save it (obviously) but in standby is a correctly date coded engine from another 68 390 GT Mustang waiting just in case.

So, how bad does it have to be before it's not repairable? I don't mind shipping it out to have this done if anyone knows a shop that really specializes in this type of stuff. What's the worst you've seen that was fixed?

Thanks guys! [img]<<GRAEMLIN_URL>>/biggthumpup.gif[/img]

Cheers [img]<<GRAEMLIN_URL>>/beers.gif[/img]

Dave

Re: Cracked Block - How bad is too bad?
 

Dave -- post some pics if possible. You say &quot;cylinders&quot; and if that is the case, have you looked a sleeving the block? TAZ

Re: Cracked Block - How bad is too bad?
 

you should do everything ya can on a numbers block..on a desirable car

technology has changed, unless its cracked thru the main webs its fixabale..

sleeves save cylinders....even if they need &quot;wet&quot; sleeves theres a fix

spray welding save blocks with windows (moper guys use this..most every hemi raced windows the blocks)..and can be a near invisible repair

and cracks can be fixed by driving pins and spray welding in combo..

they can put blocks in ovens bring to temp weld and they sit in there for 3 days to cool...

unless its a &quot;structure&quot; thats takes all the stress, theres no reason not to save a block today..just have to ask how much do you want to spend..

Re: Cracked Block - How bad is too bad?
 

Have you verified the numbers are there? The VIN derivative would be on the back of the block under the driver's side cylinder head. My experience (which is supported by a number of Ford guys I've talked to) is that VIN stamping was inconsistent in 68-70 era on FE engines. If there's no VIN derivative visible, I'd go with a similarly date coded, uncracked block. (Id also put in a stroker crank and make it a 410-445 and run 428CJ manifolds, but that's me). Sleeving FE blocks (427s especially) is common and doable, at a cost.

Re: Cracked Block - How bad is too bad?
 

We just did an LS6 engine restoration for a customer with a windowed block. He shipped the block to Europe (not as expensive as you would think) then to an engine builder in California and finally onto me. Don't quote me but I thought he said between the boat ride and cost to fix it, it was around $2000. The engine builder ran the engine hard on the dyno with no issues and best of all, I could not even tell where the block had been damaged when I got it back. There are many people that can fix these state side so no need to send it overseas but that is where the customer chose to send it. The point to all of this is, if you can save it do so as total cost to repair, rebuild and restore this engine was less than a new crate motor would cost and he still has his original numbers matching car.

Re: Cracked Block - How bad is too bad?
 

Yup, that's mine. Threw a rod back in 1981 that took out the lower cylinder skirt on the back two cylinders. Unfortunately, not enough left at the bottom of the cylinder to install repair sleeves. Engine sat until 2010, when I sent the bare block to a very respectable company called <span style="font-weight: bold">Cast Iron Welding Works</span> in England. They built up the bottom of the cylinders with the same cast iron material as the block by fusion welding. It actually cost more in shipping than the actual repair cost. Once back in the USA, Mike Lewis at <span style="font-weight: bold">Lewis Racing Engines</span> in California sleeved the back two cylinders and did all the necessary machining work, complete rebuild and dyno break in. There were no guarantees with the whole process, but I feel I made the right choices on who performed the work, including Rick Nelson for the final restoration. And the important numbers are still in place. Well, the engine project would have eventually come to light, and it looks like this is the best time for that to happen. The final picture says it all. As I have said all along, &quot;It is what it is&quot; Thanks Rick.
.
Henry D.

Re: Cracked Block - How bad is too bad?
 

Welcome Henry - thanks for chiming in! Well done and congrats. Sounds like you have had your LS6 for a &quot;few&quot; years. What can you tell us about it?!

Re: Cracked Block - How bad is too bad?
 

Now that's what is called &quot;being upfront&quot; -- no hidden agenda! TAZ

Re: Cracked Block - How bad is too bad?
 

Love it!!! OK, so sounds like this block may be saved. Yes, the numbers are there and much like Mopars of that year, some got stampings, some did not. This one matches my VIN so I know it's the right engine for my car. Also, motor mounts on the block: The one that's missing is mounted in the car, so that also is a clue that this motor came from this car. And further, the car was parked when this motor tanked by the 3rd owner and that was how I wound up with the car. The other 68 block has a partial VIN on it too. Correctly dated to my car as well, so I'll hand onto it as a spare.

So here's the damage. This is the worst cylinder.

https://www.yenko.net/ubbthreads/pics...786-crack1.jpg

This is the other one:

https://www.yenko.net/ubbthreads/pics...787-crack2.jpg

And here's my VIN which matches the door, VIN tag, sales invoice, window sticker, etc, etc [img]<<GRAEMLIN_URL>>/biggthumpup.gif[/img]

https://www.yenko.net/ubbthreads/pics...789-numbrs.jpg

So, repairable? I don't see any other damage anywhere. I realize it needs to be magnafluxed and such, but what my plan would be is to ship all this out to a shop that specializes in this stuff (like the one mentioned, and wow....NICE WORK!!![img]<<GRAEMLIN_URL>>/drool.gif[/img] ) sometime next year to get the whole engine done and dynoed and ready to go.

What you guys think? Seen worse? Is this now a coffee table?

[img]<<GRAEMLIN_URL>>/frown.gif[/img]

Cheers [img]<<GRAEMLIN_URL>>/beers.gif[/img]

Dave

Re: Cracked Block - How bad is too bad?
 

Gessford Machine has a lot of FE experience, was known for skill in sleeving.
http://www.gessford.com/

Interesting post of a 428 getting 8 sleeves
http://fepower.net/simplemachinesfor...amp;topic=26.0