jh36
Dork
5/19/22 12:57 a.m.
My ASA/Camaro/tubeframe developed a block crack. Right at the bell housing end, top of the block passenger side. Here's a rough pic.
water is coming out when it pressurizes, so I'm in the river.
I leave for Asia tonight. When I return, I have three works of pressurized work (I.e., very little shop time). HalfFast has kindly offered to help throw an engine together with me, but is there an easier way worth trying?
Yes, I'm going there.
Is it worth trying JB Weld? The internet says it will not work on aluminum blocks. The internet also says it will certainly work.
I can pick up a block and build an engine this summer, but will JB Weld stand a chance of getting me through a weekend at Summit Point?
Desperate times and all that.....
jh36
Dork
5/19/22 1:04 a.m.
In the morning ( wait, it is that already) I will go back out to the shop and get a better feel for how this crack has traveled and if a large chunk is about to come flying off. I figure you all might need to know that.
jh36
Dork
5/19/22 1:40 a.m.
This image makes me think this idea is extremely unlikely to work.
Piguin
New Reader
5/19/22 2:31 a.m.
Yeah... that doesn't look promising
The forces that created that crack will still exist, no matter what you put on top of it.
Can you order a crate motor and have it waiting for you when you get home?
jh36
Dork
5/19/22 6:02 a.m.
In reply to Woody (Forum Supportum) :
Technically, I could. I don't have that room in my race budget though. I could slow down a bit and do that for next year. A professionally tested turnkey used ls3 is about $6.5k locally.
Unless BoxheadTim is ready to take possession of my 450sel. That would be nice timing.
Woody (Forum Supportum) said:
The forces that created that crack will still exist, no matter what you put on top of it.
Can you order a crate motor and have it waiting for you when you get home?
Isn't it important to learn why a part failed as you plan to replace it? Is this a known failure point?
jh36
Dork
5/19/22 6:09 a.m.
In reply to Floating Doc (Forum Supporter) :
It appears it is not uncommon. My local ls expert thinks it could have happened with the giant jolt that happened when my driveshaft let go. That would coincide with timing. Sort of makes sense...especially as this is an 22 year old aluminum block.
I have some cylinder heads mostly held together with various forms of JB weld. Nothing structural though, and that looks like a big one.
Wow. That definitely looks like a structural/loading failure, and I am not even sure I'd feel comfortable with welding as a solution without seeing what direction that crack moved through the block. Especially in a racing application. I'm also a bit concerned that the crack is still being held open by force from somewhere. If it was a shock loaded crack, I would kind of expect it to close back up again once the load was released. Maybe it's just being held open by friction at the cylinder head/head gasket though.
Driveshaft letting go could maybe cause that....usually some part of the transmission breaks first though (in my own limited experience). Only time I've seen something like that was an application that was rigidly mounted (no engine or trans mount isolation) with 4 mounting points that weren't quite perfectly in plane, which put a bunch of force on the engine and trans once it was all torqued down and it quickly fatigued and failed once the stress of the chassis/body flexing was added to that misalignment force. Something to check if you've got rigid mounts.
That one's toast. Get bare block, drop both off with a gasket kit and head bolts to someone with more time, pick up and install?
Did you remove the transmission recently? I've seen that failure before but only from bad flexplate spacing and dowel misalignment. A TIG welder can fix it.
Yeah, you're not going to JB weld that. You might be able to weld it but you're going to have to pull the engine to get to the rest of the crack before you can do anything.
Opti
Dork
5/19/22 1:31 p.m.
Ive seen something similar on other LSs. They were always considered failures from starter installation, and they were all on early starters with the short and long bolt. The prevention was upgrade to the later starter with two long bolts and torque them to spec. Ive seen some welded, at one point someone made a bracket/brace to remount the start, but Ive never seen on get into a cooling passage before.
jh36
Dork
5/19/22 2:01 p.m.
Yep. That second pic I took made the question moot for sure.
I am closing the door on that possibility.
For those interested, head over to my build thread to see what the do!
Well then. At least you will have a block to dummy up something.
Or make a table.
Not much to add other than ouch and have a good trip.