Cracked blocks

[Fast-6.0]

To clarify some of the questions.

The hard block is effectively sealing the oil and coolant apart from each other. If a block is cracked, then the hard block is also limiting the block from moving as much (which IMO will stop a crack from growing because the block is no longer flexing as much in that area). Also if cracked, then the crack will be be filled with hard block.

My block is cracked and I have fixed it with BG cooling sealer, not using any coolant. Will it be an issue if I replace the heads? most likely but the point is, its not getting worse and my custom age studs are torqued at 250 ft-lbs. I discovered this too late (milky oil) which I know means my bearings are toast. For those that don't know, antifreeze eats engine bearings, so if you have milky oil, your bottom end is done.

The blocks aren't cracking from power, they are cracking from the headstud torque.

As far as cooling, if I were towing a 20K pound trailer, I wouldn't want a partially filled block, but that motor also doesn't need Custom Age head studs, nor a ton of the other stuff we install.

The 7.3 radiator is weak compared to the 6.4 so that is a mute point IMO and Erik's has been flawless without any fan operation and its 90 degrees here.

Any more questions?

 

[Dzchey21]

Having your crank case vent to atmosphere is goods because I noticed moisture coming from the breather tubes before I actually had substantial coolant mixing... Meaning I had sludge on the valve covers but the oil was not milky and no water drained from the oil pan. So I mean I caught it right as it happened.
I also had the bottom end out shortly after and the bearings looked fine. But yes Coolant wipes out bearings fast

Tadd I do have a question- do you worry about the bg clogging the oil cooler?

 

[IDP]

Maybe cryoing and stress relieveing the block would help. Round off all the sharp edges and get rid of casting lines and stress risers. Would be alot of work but for a build it may be worth it.

 

[powerstroked08]

Ok so can we possibly narrow this down some to ease some peoples minds. Such as if you have a cracked block, can you tell us what you torqued your studs to. Maybe if you used the "new" moly lube or not, and what stud you used ARP, Elite, or any other type such as H-11. I imagine there are some anomalies like the 190 ft/lbs cracking the block. But maybe we can see what the breaking point is in general.

Edit: maybe even list how many steps you did to get to final torque like Dustin said earlier.

 

[Super08Duty]

Pulled the dipstick and wasnt too impressed. Sludge covering the entire stick, and yes mine is milky from antifreeze entering the oil.

I torqued my arps to 325 with arp lube. Stud holes were thoroughly cleaned and dried out before I reinstalled the studs. I did 3 torque steps to get to 325. Didn't start drinking coolant until a little while after the truck was running. Sense then it's progressively gotten worse. Originally thought one of the heads was cracked until I realized the coolant system wasnt being pressurized, and there was never anything entering the coolant bottle.

 

[Stroked777]

The studs in my truck were done to the arp instructions to the T, haven't gone over the torque which said 275 iirc (I know it was done to the torque spec just can't remember the number) and the holes were blown out and vacuumed out and the studs installed finger tight, 3.5k hard miles and not an issue yet

 

[bigrpowr]

Silver surfer has ARP's with no issue. Tq'd to spec at 3 steps.

 

[FordPSD64]

this sure has me sketched out to do mine... obviously its just a chance you take I guess and it just seems to be at random. does it seem like yall are having more cases come up with arps because of the high tq numbers or is that just random as well?

 

[SSpeeDEMONSS]

Ok so can we possibly narrow this down some to ease some peoples minds. Such as if you have a cracked block, can you tell us what you torqued your studs to. Maybe if you used the "new" moly lube or not, and what stud you used ARP, Elite, or any other type such as H-11. I imagine there are some anomalies like the 190 ft/lbs cracking the block. But maybe we can see what the breaking point is in general.

Edit: maybe even list how many steps you did to get to final torque like Dustin said earlier.

Maybe also add how many times the studs have been torqued, as in taken out and reinstalled for whatever reason.

Garrett

probably getting paid at work to post this from my bionic

 

[jugger13]

Arp to 275 with supplied lube.
1st time being torqued for block and studs
5k so far no issues
Block mileage was 135k when studded.

 

[webb06]

ARP torqued to 325 with newest lube in 3 steps
Second time studs were torqued first time on block at 103k
Noticed loss of coolant at 105k and found cracked block.

This time I've got a new block and using custom aged elite studs. Hope to have it back together this time next week

 

[BFT]

DO WORK!

 

[Highroller54]

18 head studs and 2 tty bolts? Lol

 

[BBottoms]

18 head studs and 2 tty bolts? Lol

Just thinking out loud, but that doesn't seem like awful idea, actually. It sounds like there are two holes in particular that tend to crack. If you used TTY bolts, or even a lower torque on those two head studs, that could help prevent the problem.

The downside is that it will cause the block to be tweaked a miniscule amount in one way. Theorectically it could throw a cylinder out of perfect round, but we're talking 2 bolts out of 20 here so it's probably not anything to worry about.

It would also obviously create a 'weak' spot in each head gasket. However, I would much rather blow a head gasket than ruin a block.

 

[Wayne]

:doh: I've seen up to 5 different studs leaking on one side at a time. You wanna try 5 tty bolts with a completely different clamping force than studs? :slap:

 

[Highroller54]

5?????

 

[Super08Duty]

Just thinking out loud, but that doesn't seem like awful idea, actually. It sounds like there are two holes in particular that tend to crack. If you used TTY bolts, or even a lower torque on those two head studs, that could help prevent the problem.

The downside is that it will cause the block to be tweaked a miniscule amount in one way. Theorectically it could throw a cylinder out of perfect round, but we're talking 2 bolts out of 20 here so it's probably not anything to worry about.

It would also obviously create a 'weak' spot in each head gasket. However, I would much rather blow a head gasket than ruin a block.

You could screw up a lot more then just the heads by using different clamping forces. Warped heads would happen. And that could warp the block by having such a difference in clamping torque. You wouldn't use 2 factory bolts on a receiver hitch and 2 1/2" mismatch bolts.

 

[BBottoms]

Nope, 5 on one side would be stupid. 1 per side isn't ideal but I think it beats busting a block.

Was 5 leaking due to improper installation or just a really bad casting? I was under the impression that this was typically limited to a couple of the studs.

 

[BBottoms]

You could screw up a lot more then just the heads by using different clamping forces. Warped heads would happen. And that could warp the block by having such a difference in clamping torque. You wouldn't use 2 factory bolts on a receiver hitch and 2 1/2" mismatch bolts.

I'm well aware its not a great idea, just throwing ideas out there. The only other solutions I've heard are filling the block or using a new block everytime you tear the engine down. These aren't options that everyone that wants to stud a 6.4 can live with.

 

[Highroller54]

has anyone ran a 72mm turbo on a big tune on stock bolts??