010 sbc cracked head bolt holes

[pdq67]

Back again!!

I want to say that my cracks were in my heads both times!!

Water-glass worked great sealing them.

pdq67

[hwp]

Put loctite 518 on each stud assemble and forget it. I have used liquid glass/ sodium silicate and it works until you put antifreeze in it and the mess it makes in the rest of the cooling system is not worth the effort.

I have used Locktite Gasket Eliminator 510, 515 and 518 for a flange sealant , gearboxes and many other mechanical devices for many years as an industrial mechanic. It's one of the best products I have ever used for these purposes. If it works on multimillion-dollar equipment it show work on automotive equipment that costs only thousands.

[hwp]

This may be a choice as well. http://www.locknstitch.com/precision-me ... ching.html

[steve cowan]

thanks to all for your valuable input
just a general over view to answer a couple of questions that were asked
i looked at and done a measure up of this block about 18 months ago,i only wanted to purchase the block only but the price included pistons,rods,cam,oilpump etc
i really did not want the extras so i gave it a miss
moving to xmas this year-i yanked my 010 2 bolt out as was tired,it had fair compression (175psi) but had a fair amount of leakdown and was starting to blowby
this block has a sleeve in #6 as well and has 2 x cracks in the same place.on inspection with spark plug light there is slight water line on head gasket,cant really see it with naked eye unless you know where to look,talked my machine work guy and he to busy until after xmas and thinking now he would not of touched the block anyway.
so i ring friend of family as this block sitting on engine stand and like most people he is to busy so i think fresh machine block that i have previously checked with dial bore gauge etc and i figured it was a better option than the 2 bolt heap of junk
hence new pistons and then to machine shop for final hone and i was pretty excited thinking this is going to be a quick build for 2018 street car series in february
i had spent a couple days with die grinder,tap threads, vent tubes,epoxy catch screens in valley etc etc,like i said previously the top of sleeve really hard to see and cannot see it from bottom of bore
machine shop torqueplate hone block completely to spec for new pistons before they find sleeve and then cracks and then phone call to me,he only charged me $100 for labour as he feels sorry for me,he would not accept any more money,i have been around long enough and tell him not to give his valuable time away for free,but he was more dissapointed he did not see it earlier
so the deal is i ring friend as soon as machine call me and let him know what is going on,i said i call after i pick block up on friday afternoon from machine shop,i get home ring him and he says bring everything back and will refund money,no problem
i say give me a few days for some research and for me to settle down a bit as i am annoyed i wasted so much time and money over xmas and no better off.
i looked at buying a new GM 4 bolt block,$1500 aus plus machine work etc,still in situation of no machine work and yes i am being impatient which is not a good thing but unfortunetly i have found when machine shop says 4 weeks that means 12 weeks,
dart block next year but want to go 4.125'' bore and at the moment i just wanted to keep my car going while i spend 12 months parts gathering,machine work etc,i want to shoot for 550 -580hp pump gas deal
trust me when i say i have thought seriously on this deal as i hate short cutting and doing rough stuff and the risk for possible bad returns,i get it,
i have started assembly and i will use irontite,nulon etc to try as best to seal these 2 x cracks and try to monitor as best as possible
i will keep everyone informed as year goes on and if it is a massive fail i will speak up and let everone say i told you so
again thanks everyone i really enjoy this forum there are some smart kats here for sure,

steve c

[KnightEngines]

Steve - you got a better than even chance it'll hang in there till you do the 4.125" motor.

Have a good think about using keyserts in those 2 holes, with the stud in the holes with the crack, even without the twisting of torqueing them up they'll want to push those cracks open. If you use a keysert you've got a solid chunk of metal around the stud & the cracks *shouldn't* open up.
Throw in some irontite to seal it good & use MLS head gaskets so the deck can't pull.
That's how I'd do it to sleep easy.

[steve cowan]

tony,
makes perfect sense keysert those two
would you put sealer on external of keysert as well and internal since headbolt runs into water?

[steve cowan]

tony,
i ordered a few keyserts

7/16 unc thin wall
7/16 unc thick wall

best option thick wall ?

[KnightEngines]

I'd probably use the thin wall to avoid taking out any more metal than necessary.
Sealant on the outside of the insert as well, use the GM/AC delco sealant you use for head bolts.

[pamotorman]

if the insert threads are still in the cracked area I can not see what you gain and maybe lose strength in that area. JMHO

[KnightEngines]

Nah, done it in the past both ways.
Without an insert the deck pulls up either side of the crack & the crack opens up, even with a helicoil it does the same thing.
A solid insert spreads the load & the deck doesn't pull.
Insert should be wound down about 1/2 a thread below the deck face.

It's not an ideal situation, but it'll last for the required time (well, will probably last).