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Blown Rod!!! Help!!!

17K views 101 replies 44 participants last post by  pepsi71ocean 
#1 ·
Anyone ever throw a Rod on cylinder #2 I was slowing down normaly coming to a light going about 40MPH E-brake came on and BOUM... :doh:

Block has 14000 Miles on it and I have two huge wholes one on each side the smaller one I can almost fit my two fist in it and the big one well I can almost park a school bus in it. (WOuld super glue work :banghead:)

I found pieces of Crank, Cam and rods and the rod hit the ECM and now everything is a complete melt down.

any Ideas Anyone have a complete block for sale :(

I dont know why these days Bad luck after bad luck from minor stuff to my doctor telling me I have about 6 months left!!! at 36 years old it sucks. :S:
 
#5 ·
Yeah with my Sig I dont think warranty will come into play.

Any one know where I can get a new block without being rapped at the Stealership...

I got a quote this morning and I fell out of the truck...

I never seen a rod splis a block that bad!!!

I will take pictures tonight if I can get good lighting in she shop...
 
#6 ·
My e-brake always comes on when I slow down I keep it on it was cold out yesterday and I was not towing anything had the wife her two kids driving like grandpa very strange...
 
#11 ·
That is why I went with the twins and I gated it to reduce the pressure!!!

I towed with it many times and it was a dream good power low egt's fuel efficient it was the perfect set up till well... BOUM!!! :banghead:
 
#19 ·
I tow with mine all the time & I wouldn't change anything. Zero lag, low egts, and good milage. I bought a industrial twin setup first but after making several phone calls I decided to go the single route an I am very happy I did. Sorry about the bad luck.
 
#16 ·
I dont think It's more sexy you know what they say 2 is better then one!!!

yeah 6 months but it's a new truck and I want the not official wife to have something she and her kids can be safe in :( .

Figured a Cummins bullet proof :hehe:
 
#20 ·
Twins arn't the problem. The proof is in the pudding and the fact of the matter is that commonrail cracked cap rods suck. Some get lucky and milk them to 1000hp. Others throw them bone stock. If your soaking thousands of dollars into making a high hp machine then set aside $600 and buy a set of 12 or 24v machined rods. What may cost a week of downtime to swap rods could spare you a $15,000.00+ setback. Cheap insurance if you ask me.
 
#23 · (Edited)
There are a lot of guys on here taking a risk, twins or a single! These rods have been known to break with as little as 650hp. This is why I have kept my truck turned down. I know I could throw down over 800hp on a dynojet but its not worth the risk to run around and play with that hp with factory rods!!!!
 
#26 ·
Wow man, hate to hear this......it's a real downer!
 
#27 ·
These are my rods :) Carillo H-Beam



Set of 24V rods (notice right one bent)


Polish vs non polish


CR rod vs 12V rod. Notice the solid forge on the CR rod and the machined cap on the 12V rod. Each cap on the CR rod is ''cracked'' off of the forge piece so each cap is unique to the rod vs the machine process on the 12v -24v rods.

 
#29 ·
People why are y'all missing the point of the post. This HAPPEND during deceleration soooooo torque wasn't an issue, neither were rpms. This just goes back to the good old cylinder pressure issue with the 6.7. Not to say that the damage wasnt already done, but hell 3rd truck with II stocker twins $hit themselves. Hell dirty oil can throw a friggin rod.
 
#30 ·
Those rods are sweet! Would you happened to have a parts list or a website to look up 12v rods for production dates?
 
#37 ·
How are people changing them out, and how hard is it to do?

regards,
MAC
 
#38 ·
Drive pressure has nothing to do with damaging rods. When the combustion happens cylinder pressures can get over 3000psi, compare that to 80-100psi of high drive pressure and tell me wich one is going to bend or damage. Only way high drive pressure could effect the rod is if it led to increasing cylinder pressure.

The rod angle of a 6.7 is contributing to the rod failures. I used 12/24v rods in big 5.9 builds with little to no problems at all. Did the same once I started using 6.7's and bent one set after another. Yes some of those were witha Zues but at conservative timing and in the 1000hp range. Also have bent them using Smarty or H&S.

The OP's rod just happened to break while he was on the decel. Once a rod has a bend in it, especially a cracked cap style, they will flex at that point everytime the rod makes a cycle. So he could have made a full throttle run anytime before that then just be easing along and BOOM it lets loose. Just a matter of too much fatigue at the stressed bend in the rod.

I will never build another 6.7 without billet rods if its going to be anywhere over 6-700hp. Just not worth it.
 
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