after I built my last engine, I fought and fought with a water in the oil problem, I spent a lot of time making block off plates, and testing to find WTF happened. I also noticed a vibration at higher RPM, which I chalked up to a fuel issue, but I never got the water in oil issue fixed.


last month I decided to put my spare engine in my truck, because I needed the truck running.
truck runs great now,


I was finally to tear into the block and see what was going on,
I capped the lower hose, filled the block with water, and pressurized the block to 40 psi. found the block had some major cracking and spider webbing on #2 web.


got the rotating assembly out, and with a slight bump on the piece I found to be cracked the piece came right off.


when I assembled the block, I had all of the threads chased, brake cleaned and then blew it out with air.
the studs were installed with nothing but ARP thread lube.
torqueing was done in 3 steps to 95 ft lbs, in a x pattern like you do on heads.


with the piece that broke off, I can conclude that, running the studs to the bottom is not the correct way to do this. when I torqued the nut, it must have turned the stud just enough to crack the block.
fun fun fun.


ive run studs in heads many times before, without this failure.
and all done the same way.
guess that's 1 for the books!


when I rebuild, I will be loctiting the studs in the block 1/2 a turn from the bottom.


if anyone has a better way, im all ears!


so if youre running this set up, you may wanna do some research on how to install these correctly, because its obvious it can cause catastrophic damage...


just so you know!


back to work.

 

with studs ive always went by the rule of run them in finger tight then back them out like 1/4 turn. Sucks to hear, hopefully the rotating assembly is okay.

 

I suspect having the girdle in saved the block from scattering.


but you can argue if I hadn't gotten it in the first place, I would have been ok.


this isn't the first engine ive destroyed, and it wont be the last by no means.


would have been nice if there were install directions with the purchase, I don't remember any, or if there was, this block saving tip wasn't in there, or did I skip it???


maybe Justin will see this and feel like adding it to the kit.


its a great girdle, it laid down flat and all other bolt bosses were fine, but I found the weak link.


im not placing blame on R&D, I know its 100% my fault.


but I did have other issues that I see now, and will plan for in the future.


anyone have a .020 over block forsale? lol
I have a virgin block, and a turbo block coming with turbo pistons.
I will be rebuilding for my 63 ranchero.

 

I think it does say to only run them in finger tight or so many words, but dont quote me.

 

like I said I know what happened,
but I can tell you that it wasn't in big red letters large enough for a IDIoit to read it lol

 

One question - what does the bottom of the two studs in #2 look like?

Also, just a thought:
I'm seeing the threads ending in your broken piece /below/ the break on the side which broke clear through.
On the whole-thread one... it sure looks like there are still a couple of threads in the block. In which case... was it really the studs that broke it?

I'm not sure here, but I wonder if the girdle had something to do with it. Perhaps:
1. If the top of #2 was just a hair lower and the girdle was "pulling" on it constantly or
2. Uneven expansion during heat/cool cycles between the cast iron and steel or
3. Something involving stresses?

I don't have any better idea than you do; I'm just really wondering if the stud being torqued down really cracked it...

 

the stud did not look knurled. not like you would when you tried to put too long of a bolt in a blind hole. I didn't get a pic because of no alarms.


im no professor, but I firmly believe that when I torqued that nut, it torqued the stud to the end of the thread in the block and cracked it .
I mean its split down the center of the threads.
and then cracked from there to either side of the bottom of the cylinders.
I see no other logical explanation.


I would suspect the plate, if it didn't sit flush with the mains, but there were no issues. I checked, no end to end flex.
but if the block was somehow not true to begin with, I would be finding linear cracks on the inside?


when I first got it running, I never worked it hard, I gave it some spikes, but I drove pretty slow. the issue was apparent from the first 5 miles of it running.


perhaps the cap was off? maybe I should chuck em up on the surface grinder next time.


miss anything?

 

That's what I was thinking. I'd expect some chewed up or 'cut' threads right at the bottom where it would attempt to 'tap' it's way deeper.

One alternate explanation: What if it started at the inner edge, or at the inner bolt, then cracked straight up the threads of the outer bolt as the weakest point.



So definitely not heat related then.

Maby. I don't know.

I really don't know, I'm just thinking that with the threads /not/ chewed up from being driven too deep... there has to be something else going on here.

 

the only thing I did notice is that stud had "milkshake" on it.
and that cap was surprisingly loose, the others needed a plastic mallet to get off


after studs were out...

 

Wow, thats some carnage there.

Looks like a textbook bottomed studs situation. The stud bottomed out, the torque on the fastener is trying to pull the treads out of the hole, but because of the nature of the block there, it just split the web at the weak spot which is the area where the stud is bottoming out in.

The girdle itself had nothing to do with it, its whole purpose is to hold the main caps in place, and it actually has a little flex to seat on each cap evenly.

The Girdle kit does come with a direction sheet, its usually behind the invoice when I ship things out. But basically all it says is to install the studs and torque them in 3 steps to 110ft/lbs in the factory sequence. I will update the installation info now however, Ive never seen this actually happen.

 

I would have to agree and disagree with you all in 1.


with youre experience, I would have to agree with you 100% that it was the torque of the nut that did it. its ****ty, but that's what happened hands down.


but the girdle did play a vital part!
because, without that girdle, I would have most likely scattered the rotating assembly!
so a thanks are in order for your product saving me some cash.


its been over a year since I purchased this item, so what was actually on the directions is kinda fuzzy to me.
I would greatly appreciate you adding the correct install procedure to your directions, it may save someone elses ****!
luckily enough the only real thing that's waisted was my time.
woulda really sucked for someone else who had spent a buncha coin on it.


well now I get to play with a torch, and gut the inside of the block! because I now have a mock up engine lol

 

I personally have had girdles in 3 trucks, and I probably have 25 or so of them out in service, including my fresh bronco engine that has already done 425whp... At 110ft/lbs. So no, I would not say its because the nuts were too tight. You can look right at the break point and see that it cracked right at the bottom of the thread, and up the outer bolt hole.

It sucks, I feel bad it happened under my product, but being this is the only failure to date related to main studding an IDI, its either a case of bottomed out studs, or a flawed block.

 

Just a random other idea:
I wonder what would happen if the bolt hole was full(or partially full) of liquid at the time of torquing the stud down?

I recall one video discussing rebuilding an AC compressor, and a warning being given to make sure that the (aluminum) cast holes were blown out with compressed air, or when tightening down the bolt you could crack it due to hydraulic pressure.

Now cast iron is a lot harder than aluminum, but the stud is larger and presumably would take more torque in the tightening stage.

Also, depending on the liquid involved, you'd have some expansion as the engine warmed up... not sure if you ran it long enough for this to be an issue though.


Any thoughts about this?

 

don't feel bad. its not like it was a remaned block you sold me. lol
this is hotrodding, and I know all too well what can happen.
operator failure, or mechanical failure, they happen.


what I ment by torqueing down the nut, is that when I put the stud in, I did it with a hand driver. I did not tighten the stud to any torque but barley hand tight.
after the girdle and the fasteners were on,
when I torqued the fastener, it actually torqued the stud down with the nut.
hence torqueing the stud into the block too much.

 

while, in fact this will do it, it is not possible in my situation. that block was surgically clean before I operated on it.
every single thread was chased, brake cleaned and blew out. the night before assembly.
and I blew it out again before assembly.
special attention was given to each hole I used a stud, for the fact that I had damn near a grand in studs.