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mstockton
02-09-2009, 18:20
Read up on Robyn's Lock n Stitch repair thread, and I need some advice. I just got my second engine, and its got cracked mains as well. 4 total. They all are within the bolt thread, the longest one at 1". Now I contacted the people at Lock n Stitch, and they are going to get me a quote tommorow on the cost of the repair. I don't mind the cracks, but also its got two scored cylinders, one of which will probably need to be sleeved. With all these repairs, the cost just isn't going to be worth it. Anyone have any idea on the cost of the sleeve job?
Both of these cracked blocks are red blocks, so I think I'm cursed. Found another engine at a local yard today (also a red block), it will be 180 for the short block, so I think I might risk another catastrophe to avoid the machining cost. I'll pull the engine out of the truck its in, pull the heads and drop the pan and do the best inspection I can before I part with my money this time. I think this is my best bet, anyone with any opinions?

-Martin

john8662
02-09-2009, 19:00
Why are you considering sleeving? It won't clear a .040" overbore? The typical is to bore all 8 and install oversized pistons, commonly available.

Ditto on the red block thing. I'm starting to form the opinion that the 82 block ain't better in the cracking on the bottom end. They are better on wear, and maintaining a good deck, but I think they're just harder, not more crack resistant.

Lemme know on the bore thing...

mstockton
02-09-2009, 19:33
I was planning on having to clean up all 8, it has some wear, but I think my gouges are over .020" deep. Something got in between the crown and the cylinder wall. Got a gouge running top to bottom on number 6. Number 2 as well, but it should clean up no prob.

Thats why I was looking at a sleeve.

The overbore cost doesn't bother me too much, I was going to install lower comp. pistons to go with my hy-35 turbo. Need to handle 15 psi or so. Girdle and headstuds are going in as well. But if it needs a sleeve, thats getting pretty steep.

john8662
02-09-2009, 22:04
If it's .020" thick gouge then a .040 overbore will clean it up, just barely.

Best advice is to have a machinist measure and take a look at it.

Bad gouge from the sounds of it though.

They do make a .060" piston for the 6.2L blocks too, Mahle does (as of last look at the book). But, since you mention turbo service, a .040" is best.

Robyn
02-10-2009, 07:12
After having several Red blocks go through on deals/trades etc I agree that the lower end cracking issue is a crap shoot at best.

Some seem to last forever and the next one that even though it belonged to a little old lady that drove it only on Sunday to church will be cracked.

There seems to be no particular basis to judge what you will find except to open them up and look.

The cracks in the bottom end dont worry me so much any more unless they are below the bottom of the bolt holes.

With the cracks that are still in the upper area of the threads it is way good. Just insert the thing and be done with it.

Nasty gouged up cylinder walls is another matter.

I would be hard pressed to take a 6.2 past .75mm oversize

The normal oversizes on Pistons is .25mm,.5mm and .75mm
I believe I have seen a 1mm OS but not sure
1mm = .03937" so the .75 may not clean it as your only going to see 1/2 that amount on a side

I looked at a buttload of GI blocks recently and a goodly percentage of these had nasty looking cylinders that likely would not have cleaned, many would be lucky to clean at the water line :eek:

Me thinks some of these were run until they gave up or may have come from a combat zone where getting the rig and it people to safety was far more important than an engine.

I must have looked through over 100 blocks and other piles of scrap Iron.

If your block is that much in trouble, a trip to craigs list or ??? may be a good deal to see whats available.

A couple small cracks in the bottom is no biggy, but some good cylinders would be nice for sure.

Good luck and keep us informed

Robyn

arveetek
02-10-2009, 15:44
You could always bore .080" over and install 6.5L pistons.

What?? It's been done! :D

Casey

Robyn
02-10-2009, 17:30
A late 6.2 in a 599 casting will go the .080 with ease.
I would be a bit squemish at that point on a 6.2 early block

RC

john8662
02-10-2009, 23:40
FYI

.50mm = .020"
.75mm = .030"
1.00mm = .040"

common os

Robyn
02-11-2009, 08:00
Looks like what I have here on the wall in the shop. #### :)

I have never seen any pistons larger than .75mm os for sale locally.
Does anyone make the 1mm os or larger for the 6.2???

RC

john8662
02-11-2009, 13:45
Looks like what I have here on the wall in the shop. ####

Not what you said up in post #5 here (http://www.thedieselpageforums.com/tdpforum/showpost.php?p=249715&postcount=5)




Does anyone make the 1mm os or larger for the 6.2???



Yes, Mahle-Clevite does. A .040" and .060" are available OS for the 6.2L

.040" = 1.0 mm *
.060" = 1.5 mm *

* Over Stock 101.00mm sized (STD) piston.

I'm also pretty sure that Sealed Power makes a .040" piston size too (not .060 though, this is new and odd).

mstockton
02-11-2009, 17:50
Well I was at the international ag expo yesterday, and ran into a fellow from a company that has lots of engine parts. Says he can get me a good 6.2 block for $550. Even if it had cracks, I could have somewhere to take it back to. OR I can go to another scrap yard this weekend and pull another 6.2 ($180) and get it out of the truck, and drop the pan in the yard and check it out. Not sure which way to go with this deal. I think with the machine work to the block I've got, I'm going to reach the 550 number (lock'n stitch plus machine work to cylinders). Just not sure if I want to risk the effort of pulling another engine, or just spend the big bucks and have a sure thing.


Martin

Robyn
02-11-2009, 17:50
I will clarify
I have seen .25 .5 and .75 mm OS in person.

I have never seen and 1mm OS
And as far as what I have on the wall. Just a Metric conversion chart :)

RC

john8662
02-11-2009, 19:23
Says he can get me a good 6.2 block for $550. Even if it had cracks, I could have somewhere to take it back to. OR I can go to another scrap yard this weekend and pull another 6.2 ($180) and get it out of the truck, and drop the pan in the yard and check it out.
Martin

I like idea of both, but I'd make the $180 yard pull it for me though. But if they'll let you pull the pan and look before you commit to buy, that's cool.

It's sometimes difficult to find a good builder. Once you find one (and you will) make sure and put at least a stud girdle kit on the bottom end.

J

mstockton
02-14-2009, 22:09
Hi, found an engine up in northern california, looks like its very low miles, very clean, but most of the outer holes are cracked. Engine number 3 is also cracked. I'm thinking I might just have Lock 'N Stitch repair all six holes no matter what. Anyone know how much this repair costs a hole from them? Got to head back to so cal tomorrow and need to let the guy know if I'm going to pick it up tomorrow. Thanks in advance,

Martin

Robyn
02-15-2009, 09:10
Call them up and ask their service dept (800-736-8261 )
They offer the service on site, remote site or ???

They sell the tooling and inserts too $$$$$ though

Here I charge $40 a hole if the block is clean. If I have to steam it so I can get close to the beast I charge time and materials for that service.

So far my clients have been all :D:D:D

Robyn