DerrenC

I have a low mileage LS1. A mechanic from a local speed shop thought there was a knock coming from the lower end.

So I dropped the pan and pulled the rod caps. All the bearings look good as new.

But now, how do I bolt it back together?

These are 2nd design bolts, but they are still torque to yield, and yes I have seen the technical bulletin that these bolts can be re-used a couple three times by increasing the torque angle to 85 degrees.

But just putting it back together makes this the 2nd time for these bolts. And because I wasn't sure I was doing the 75 degree part right (per the manual) I re-torqued them. Well that really makes 3 times these bolts have been torqued, and I really need to loosen them and take them up to at least 85 degrees.

So that's like 4 uses isn't it? Some of these bolts may be stretched too far and I don't have the equipment to know for sure. Some recommend ARP or Katech bolts, but I really don't need to increase the capacity of the system, it's just going to be a tame, stock DD. And since the caps have been removed, I can't really do the "leave-one-torqued-while-replacing-the-other" thing with the cap bolts.

What is the right way to simply put it back together without taking my motor to a machine shop? I just want to put my caps back on...

crainholio

iTrader: (2)

Just get a new set of GM 2nd design bolts from your favorite dealer or online source.

DerrenC

Alright, then use the original 15 ft. lb. plus 75 degrees I assume?

And by sticking with a factory bolt, there is no distortion issue like with aftermarket bolt upgrades?

Thanks for taking the time to reply.

chrisfrost

iTrader: (8)

You have the bolts that utilize the spacer or bushing in the cap ? If so , I've got a good set that I removed that have been torqued once that I would sell You for $20 or just torque You'rs . I can send pics if You'd like .

DerrenC

I don't believe there is a spacer or bushing in my cap. The bolts do not fall out of the cap when removed. I'm told these would be 2nd design bolts.

Dunno if you can tell anything from this, but it would be nice to have someone confirm for me that I have 2nd design bolts:

garygnu

from what I have read ,if you remove the rod caps the big end of the connecting rods needs to resize the rod..these are cracked rods.ls2 rod caps are good, some what better then ls1 rod bolts.consider some kaltech or ARP rod bolts.

DerrenC

Are you saying that simply removing the rod caps requires you to have them resized in order to re-assemble?

DerrenC

Here's a better pic of the bolts I have:



Is that 1st or 2nd design?

chrisfrost

iTrader: (8)

You just have to make sure that the caps are lined up with the rod when You torque the bolts ,,,,,,,,,,,,,,,in other words like the previous poster said when they manufacture these rods they ( I believe ) they laser etch then crack the cap off so each cap is unique to the rod and the cap only seats with the rod in 1 position correctly . What I've noticed working with these rods is if You ding the mating area by accident that makes it harder to get the rod and cap to line up and mate correctly . Also dirt and/or metal pieces or debri makes it hard to get them to mate so make sure they are clean and be careful handling them and You should be fine .

DerrenC

Thanks Chris.

Yeah, I'm pretty clear on how the caps go on, etc. What gets unclear is when and why you must resize the rods. I just want to bolt it back together!

So it sounds like (except maybe what garygnu said above) that with either Katech or stock bolts I should be ok without resizing.

Say, if I go back with GM oem bolts, do I go with dry threads and one round of torque (as opposed to loosening and repeating the torque 3 or 5 times as recommended for other bolts)?

black00ssFL

iTrader: (24)

Get new bolts (stockers), torque to 15ft lbs and then 75 degrees, no need to keep retorquing. Only need to resize when there is more clamping force and causes the rod end to be out of round. This isn't magic, it's just a rod cap.....the internet has made this way too complicated than what it is. And don't install the bearing dry. And, you can put some oil on the threads if you'd like. Being that they are angle torqued...getting an actual resistance measurement isn't as important.

DerrenC

Yeah, it has become complicated, and I just don't want to get such a simple thing wrong. Leads me to create dumb sounding threads like "How do I install my con rod cap?"

Thanks for the reply!

1of625

I noticed you did not number the cap in the picture and you had stated earlier that you had removed all the caps???
I hope you are doing one connecting rod at a time since I didn't see the cap numbered in the picture and I hope you have the caps marked which way they go back onto the connecting rod.

DerrenC

Yes, I removed them each individually looking for any signs of problems on the bearings. No trouble found, just need to bolt it back together. If only I could find stockers locally... I think aftermarket are sold more than oem.

chrisfrost

iTrader: (8)

You don't need to # the caps as they will only fit one rod . If You remove the pistons/rods from the block then You should mark them as to which cylinder they were removed from .

DerrenC

OEM stockers should be in today. I'm not building or racing this motor so they should work fine.

To get the correct torque, should they be installed dry or oiled?

black00ssFL

iTrader: (24)

Shouldn't matter, the 15ft lbs isn't as important as the angle. And it doesn't matter if it's oiled or not for the angle. Follow any instructions that may come with the bolts. I would also throw some assembly lube on the bearings when installing. Change oil after a good warm up. Find a local Lucas dealer and buy their assembly lube. I paid around 6 bucks for a bottle.