View Full Version : Cracked Block - How bad is too bad?
A12pilot
09-14-2016, 12:26 PM
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... <<GRAEMLIN_URL>>/hmmm.gif I'm unfamiliar with repairing engines as far as how bad a crack can be before the block is deemed unblockable <<GRAEMLIN_URL>>/biggthumpup.gif 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! <<GRAEMLIN_URL>>/biggthumpup.gif
Cheers <<GRAEMLIN_URL>>/beers.gif
Dave
earntaz
09-14-2016, 12:55 PM
Dave -- post some pics if possible. You say "cylinders" and if that is the case, have you looked a sleeving the block? TAZ
marxjunk
09-14-2016, 02:12 PM
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 "wet" 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 "structure" 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..
tom406
09-14-2016, 03:02 PM
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.
SS427
09-14-2016, 03:10 PM
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.
Henry D
09-14-2016, 05:53 PM
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, "It is what it is" Thanks Rick.
.
Henry D.
mockingbird812
09-14-2016, 06:29 PM
Welcome Henry - thanks for chiming in! Well done and congrats. Sounds like you have had your LS6 for a "few" years. What can you tell us about it?!
earntaz
09-14-2016, 06:35 PM
Now that's what is called "being upfront" -- no hidden agenda! TAZ
A12pilot
09-14-2016, 08:28 PM
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.
http://www.yenko.net/ubbthreads/pics/usergals/2016/09/full-18993-48786-crack1.jpg
This is the other one:
http://www.yenko.net/ubbthreads/pics/usergals/2016/09/full-18993-48787-crack2.jpg
And here's my VIN which matches the door, VIN tag, sales invoice, window sticker, etc, etc <<GRAEMLIN_URL>>/biggthumpup.gif
http://www.yenko.net/ubbthreads/pics/usergals/2016/09/full-18993-48789-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!!!<<GRAEMLIN_URL>>/drool.gif ) 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?
<<GRAEMLIN_URL>>/frown.gif
Cheers <<GRAEMLIN_URL>>/beers.gif
Dave
tom406
09-14-2016, 09:09 PM
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/simplemachinesforum/index.php?PHPSESSID=mi63etjmihffpmbjtgn6lbvt20&top ic=26.0
earntaz
09-14-2016, 10:35 PM
Sleeve it ... work good, go long way ... <<GRAEMLIN_URL>>/beers.gif
ZLP955
09-14-2016, 11:06 PM
Not to hijack, but if a block has at least one sleeve installed, is it necessary to deck the block to true up the deck/sleeve interface?
SuperNovaSS
09-14-2016, 11:12 PM
Yes, the top of the sleeve needs to be brought to deck height. Many shops will use a boring bar to true up the deck surface if numbers/broach marks need to be saved. Others will stop the surfacer before the numbers but after the gasket area.
Jason
Henry D
09-15-2016, 05:21 AM
<span style="font-weight: bold">"Welcome Henry - thanks for chiming in! Well done and congrats. Sounds like you have had your LS6 for a "few" years. What can you tell us about it?!"
_________________________
Sam</span>
Sam:
I bought the car back in 1978. Black, white stripes, red interior. Original drive train, build sheet, and POP. Parked it in 1981, and only started to restore it in 2010. Registered on the National LS6 Registry.
.
I can say now that a damaged block can be restored successfully, but it was not a cake walk. In the early days this block was deemed junk and could not be saved, but I hung onto it anyway. Modern technology has changed all that. It took plenty of research and pre-planning to accomplish what I wanted. It took from 2010 to get the engine to where it is now. A competent fusion welding firm can take a piece of cast iron equipment like an antique engine broken in three pieces and successfully put it all back together and be as strong, if not stronger than the original. Along with the Fusion Welding process, a four (4) axis machining center would be the next recommendation I could make for the machining process. That equipment in the right hands can work wonders for this type of project. It can feeler probe the entire block and compare the existing dimensions to the original factory blueprints and allows the operator to make corrections to a blueprint level. We have come a long way, I just had to be patient.
.
Henry D.
A12pilot
09-15-2016, 11:11 AM
It's great to hear this! Sounds as though it can be repaired (whew!) so I'm pretty excited! The only part that doesn't match right now on the engine is the distributor, but my Ford guys say that's no big deal to find.
Thanks for the leads on engine shops too. <<GRAEMLIN_URL>>/biggthumpup.gif
Cheers <<GRAEMLIN_URL>>/beers.gif
Dave
Tracker1
09-15-2016, 11:58 AM
This is a block I had from a '69 Dodge Daytona a few years back - I was given the name of Bob Himes to repair it. I sent him the pics and he told me "No problem". I never did get it done as I sold the car later but he came highly recommended for cast iron welding - He was in Indiana - 317-831-8069
http://www.yenko.net/ubbthreads/pics/usergals/2016/09/full-3497-48807-daytonahole.jpg
A12pilot
09-16-2016, 05:45 AM
Awesome! That's good to hear. Thanks for the other lead!
Cheers <<GRAEMLIN_URL>>/beers.gif
Dave
vBulletin® v3.8.11, Copyright ©2000-2025, vBulletin Solutions Inc.