Duramax Diesels Forum Truck of the Week
  #1  
Old 01-12-2019, 06:14 AM
reese600 reese600 is offline
FNG
 
Join Date: Jan 2019
Posts: 9
Default Rod caps??????????????????

Ok, so I'm disassembling my LBZ bottom end to get the crank out so I can get it keyed. When I took the rod caps off, I find they look like the pics below. All 8 of them. This is the first Duramax that I have torn into the short block. In my 30+ years of turning wrenches, I have rebuilt many types of engines and I have never seen rods that look like this. Where the rod separates, any other engine that I have had apart, these areas have always been machined surfaces. What the hell is this? There is no other broken piece of the rod to be found, they look like they are made like this, but it can't be right, can it?
Attached Images
File Type: jpg 20190111_195230_resized.jpg (114.7 KB, 59 views)
File Type: jpg 20190111_195239_resized.jpg (129.8 KB, 54 views)
File Type: jpg 20190111_195246_resized.jpg (110.7 KB, 46 views)
Reply With Quote
  #2  
Old 01-12-2019, 06:25 AM
Blackmax123 Blackmax123 is offline
Hotrodder
 
Join Date: Aug 2014
Location: central Pennsylvania
Posts: 599
Default

That's completely normal.

The rods are made as one piece and they use a method called crackingor split fractured to break the journal side of the rod in a targeted manner while its bolted together. This achieves a precision fit between the rod shank and bearing cap.

It also prevents the bearing caps and rods from getting mixed up and they will only go together 1 way and every rod cap is different.
__________________
2013 Chevrolet 3500hd duramax loaded ltz cc/lb dually (tow pig)- built motor by me, exergy 10mm cp3 swap, danville 2.5 stg1.5 charger, 5" afe exhaust, wehrli charge piping and egr delete,wehrli stainless downpipe and danville tuned. 5" zone lift, 315/70r17. 2" hub centric front spacers 3" hubcentric rear spacers between duals.

2008 Chevrolet 3500hd duramax ltz cc/lb dually (homemade handgrenade) built motor by me, Built tranny by me, big exergy pump and s&s over it, large exergy lbz injectors, ac delete, custom Danville s400 true 2.5 charger, roll pan, 8" single stack, custom hitch and a few more pulling goodies.

2015 Vw passat tdi sel premium blacked out(old lady's ride)

2014 chevrolet cruze diesel work car.

Special thanks to Danville Performace & Limitless Diesel
Reply With Quote
  #3  
Old 01-12-2019, 06:40 AM
reese600 reese600 is offline
FNG
 
Join Date: Jan 2019
Posts: 9
Default

Blackmax123 - seriously, that is how they are made? I was getting ready to tear my other LBZ apart and see if the rods were the same in it.
Reply With Quote
  #4  
Old 01-12-2019, 07:03 AM
PureHybrid's Avatar
PureHybrid PureHybrid is offline
Isuzu Shakes IT
 
Join Date: Feb 2012
Location: Central OH
Posts: 2,347

Default

A lot of modern engines have rods manufactured in the fracture split manner. Even some aftermarket rods. Completely normal. BUT do not mix them up, and if you attempt to bolt one together with the wrong cap (which will be obvious if you're paying attention) it will ruin the split surface and your rod will be scrap.
__________________
04 GMC ECSB LLY - Mix breed trans/SC1056 - Profab - PPE - Kennedy twin pumps/pickup - Danville tuning: 531/944
I can't complain, but sometimes I still do
8.17@84mph 1/8mi
Jesse
Reply With Quote
  #5  
Old 01-12-2019, 07:06 AM
reese600 reese600 is offline
FNG
 
Join Date: Jan 2019
Posts: 9
Default

ok then, I just watched a couple videos on cracked rods, I guess the GM LS engines have them too.
Reply With Quote
  #6  
Old 01-12-2019, 07:22 AM
gmc502 gmc502 is offline
Hotrodder
 
Join Date: Jan 2011
Posts: 364
Default

Quote:
Originally Posted by reese600 View Post
ok then, I just watched a couple videos on cracked rods, I guess the GM LS engines have them too.
hope your mind is at ease now.cracked cap technology has been around for awhile now,excellent at alignment.
__________________
2002 GMC 2500HD, ECSB, 4WD, LB7,300k miles and still truckin
new style gm exhaust manifold, banks big head wastegate, PPE boost valve, banks air intake,high idle switch in cruise control, stock but not for long
EFI live tuned byMe now,dps5 switch,EGT probe and autometer boost sensor,SoCal 6spd conversion
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -7. The time now is 11:06 PM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
vB.Sponsors