Broken Crankshaft Count?

[THEFERMANATOR]

I know WDINO73 lost a crank in his built LB7 as well. As for the seasoned block theory, there may be some truth to this. I know the 6.5's have a history of cracking in the main webs on the new style squirter blocks, but blocks that seem to last to 100K miles or so without cracking seem to hold up to most anything after that. They also have problems with heads cracking between the valve seats, but seasoned heads without cracks seem to last as well.

 

[paint94979]

my factory lly engine is still good (135,000 miles), hope I dodge all these bullets, sorry to hear about your bad luck Ben, hopefully # 4 is the last

Larry you need to run some man tuning... those twins should make 800+ on stock injectors.

 

[ripmf666]

I just have to laugh, ironic that out of the 3 motors that have been in my truck, the one I ran the hardest with the littlest care to anything was my stock factory original engine...and everyone says LLY's are junk... : That made it 85-someodd thousand miles before cracking a piston. My "BUILT" motor lasted 15,000. This stock LBZ POS short block lasted about 50,000. Wonder how far Ill get on lucky #4. :joker:

ben

Sorry to hear but how many miles were on the LBZ before you installed it?

 

[duratothemax]

Sorry to hear but how many miles were on the LBZ before you installed it?

no idea...it was a GM test engine. So I guess 0 "miles" in an actual truck, but who knows what GM did to it when they were testing it on the dyno.

 

[Leadfoot]

no idea...it was a GM test engine. So I guess 0 "miles" in an actual truck, but who knows what GM did to it when they were testing it on the dyno.

Sorry to hear that Ben.

If you need a hand, let me know.

 

[JD4440]

Ben; Ed (05Smoker) has an LBZ for not too bad a price if you need to source one.

 

[duratothemax]

heres mine. I uploaded it on my photobucket instead of youtube because I didnt want to hear a million laughing responses from the cummins and powerstroke dipshits. Interestingly enough I still have 'normal' oil pressure, and my balance rates are all more or less within spec.

 

[S Phinney]

Sounds about right Ben. I wasn't lucky enough for it to run that long. It only cranked three times afterward.

 

[JD4440]

Man that's an awful sound.

 

[Jared Duramax]

This makes me think more and more about going back to completly stock. i know it hurts to even think about it.

Good luck Ben PM me i have some things you may be interested in.

 

[MACKIN]

Man that's an awful sound.

I thought the same thing. More interesting,atleast I think so, is the motor still runs without tearing itself up with a broken crank.

 

[Cougar281]

This makes me think more and more about going back to completly stock. i know it hurts to even think about it.

Good luck Ben PM me i have some things you may be interested in.

But that can happen even stock... I think many more pistons have cracked than cranks broke. I'm nervous as hell about the LBZ pistons and can't wait to get the LLY shortblock back in with the LBZ top end. I was going to run stock tuning until that point to minimize the likelyhood of cracking a piston, but I broke down and added about 40hp as I couldn't stand stock power any more.

 

[duratothemax]

I thought the same thing. More interesting,atleast I think so, is the motor still runs without tearing itself up with a broken crank.

oh yeah, still runs "fine". It will rev up and like I said, oil pressure is normal.

Ive driven it around my yard and up and down my driveway too (who gives a shit at this point, what am I gonna do, hurt it even more?? )

ben

 

[DIESELMAFIAPER.LB7]

I wondering if mine will last these cranks are so far out from.the factory I race balanced mine power is so smooth as well as idle think at 3 k it was @66.78 lbs of force noe its like 1.68 ounces I shaved weight on everything an had it all balanced really well hope mine lasts this an good luck to you Ben sorry to hear the luck

 

[Rhall]

oh yeah, still runs "fine". It will rev up and like I said, oil pressure is normal.

Ive driven it around my yard and up and down my driveway too (who gives a shit at this point, what am I gonna do, hurt it even more?? )

ben

I made 2 passes at scheids with a broken crank. Oil pressure was fine, you couldnt hardly here anything, and it ran pretty smooth. It still made a 7.1 @96mph pass in the 1/8th with one cp3 cause it wouldnt keep the belt on cause the balancer was wobbling, it would throw it when it shifted to 2nd. It ruined one billet main cap, but the block was still good.

 

[duramaximizer]

oh yeah, still runs "fine". It will rev up and like I said, oil pressure is normal.

Ive driven it around my yard and up and down my driveway too (who gives a shit at this point, what am I gonna do, hurt it even more?? )

ben

Ya, sounds like what the wrecker opperator said when he picked up dads truck. Then when they got it to the dealer the tech started it up and drove it in after they sat there and listened to it for a minute. The block was ruined on dad's.

 

[isuzulb7]

I currently have a broken crank I purchased a lbz short block hopefully that will hold together.

 

[duratothemax]

I currently have a broken crank I purchased a lbz short block hopefully that will hold together.

good luck!

 

[GeorgiaDieselGTO]

How many miles on the trucK?

 

[DIGGLER]

'nother broke LBZ crank here. 250k on it and i do not believe it ever had a tuner or any other mods on it.
broke behind the #2 rod journal, and the crack runs all the way through the counterweight.