Well my build didn't last long. Was driving up to cars and coffee here. Was going 75mph on the highway when I noticed the knock sensor started going off. I turned the radio off and didn't hear anything but to the next exit. Made it into a parking lot and there was a light knocking noise. I popped the hood and couldn't see anything wrong but didn't want to try to start it so I towed it home.

Was thinking I broke a valve spring or something. I took the valve covers off and the plugs out. The front passenger plug was black which was the only strange thing. All the springs, rockers, pushrods, etc all looked good. I couldn't figure it out. I then pulled the valley plate and that is when I found the damage. The front cam lob was wiped out and the roller of the lifter was gone.





The roller tip of the lifter is snapped off. Not sure what the plan is besides continue to tear it down. Very least it will need to get a new cam, new lifters, etc but if I'm going that far I may just pull the motor and build it or buy a new motor and swap it in.

Ohh well, ran really good for 750 miles.

 

that sucks.... 750miles only! sorry to hear that who did the build? and what does it consist of exactly? I remember readying some of your posts. I know you have a lethal cam I think and A&A... but not sure if your engine is built (internals?).... GL anyway

 

Stock short block. Texas Speed Heads. Comp 228/234 cam. I put it together myself. Ran fine until this happened. Not sure what could have caused it. Looks like maybe the lifter spun in the bore and then snapped the end off.

 

Sorry to hear about this. You can't seem to catch a break.

 

that sucks, i followed your build and know you went through some B.S. along the way, hope you get it all sorted out and the damage is minimal.

 

Not sure if this was a random freak failure, installer error, bad parts, or what. I should know more later. Talking to people I guess lifter failures aren't that uncommon in the LS world.

 

Cam bolts backed out?

 

That truly sucks I would at least put forged pistons/rods with the new build if you decide to stick with the LS7. All the best!

 

This would be my guess as well. Did you use a 3 bolt cam?


I destroyed a LS3 crate motor due to bad GM torque specs on the internet for the cam bolts. Motor lasted about 500 miles. All the metal from the cam got dumped onto the pistons and took out the cylinder walls in 6 cylinders. I used a copy of GM torque specs that listed the torque as 18 ft lbs. Cam bolts should be torgued to at least 26 Ft Lbs.

I recomend ARP bolts @30 Ft lbs with red loctite.


Time for a stroker shortblock.


DJ

 

Well shiiiite, i just got done swapping in a cam, and my torque sheet says 18ftlbs as well. fml

damn, ls1howto.com says 26ftlbs.

i did brake clean all the oil off the bolt threads and cam bolt holes, then blew out with compressed air. then applied red loctite.

-Carl

 

I changed timing chain 6k miles ago 18 ftlb no loctite. I'm ***'ed.
I guess i might be doing my 434 built sooner then later. Time to remortgage the house again. I hate my vette.

 

Suggestion...spend a Saturday and go back in and loctite properly plus 26ftlb. Very little cost other than your time. The alternative ain't so good!

 

Ahh the joys of the internet. So I checked the C6Z06 torque guide that I got from this site, and yep, 18 ft-lbs. Then again I used 18 ft-lbs the first time and that never came apart. I did use blue loctite. I guess I was gambling and lost this time if that is what happened. I can wiggle the cam gear so good odds that it came loose. Shouldn't the cam retainer plate hold the cam in place?

I see two options I have now.

Option 1:

• Reuse current block
• New Cam (nice custom blower cam this time)
• New lifters (OEM or other?)
• Forged pistons on stock rods/crank (if all that is still good)
• New bearings, etc.
• New cam bolts, gaskets

Option 2:
Find a core block. Send it to RED or ERL to get sleeved to 4.125". Friend has a gen 4 aluminum 5.3L I can have cheap.
All new rotating assembly. Pistons, rods, crank, etc.

Time to start pricing stuff out and figuring out exactly what I need.

 

i guess we need to stress 26 to atleast a minimun of 30 ft lbs for cam bolts, i just did my black mamba cam back in august and i did use red loctite and after the 18 ft lbs i did give it a little extra turn, only put about 400 miles since then but so far so good, hope im not FUKED!!

 

Local friend has a spare gen IV aluminum 5.3L block. Thinking of picking that up and sending it to Steve@RED to get darton sleeved. The picking up a crank, rods, pistons. Need to start a parts list. Vendors, feel free to help me out. End goal would probably be a reliable nice 730-750rwhp motor. Nothing too big or crazy. Probably swap the Si-trim for a T-trim/Novi 1500 and just run that to get my goals.

Brands of pistons? Rods? Cranks? Other parts/etc I need or should look into?

 

That is what my turbo motor is. Steve charged me 1,960.00 for new darton sleeves, rough boring it to 4.120", decking the block, and drilling the block out for 1/2" head studs. If you dont do the 1/2" studs, you save 250.00.
The turn around was about 2 weeks. He was great to work with..

Just make sure it is a Gen IV 5.3. You do NOT want a Gen III.

 

Yah it is a gen IV AL block. I'll double check. Right now that sounds like the route I'm going. I'll need help picking out all the options I need, or if the local block doesn't work finding a core. Since my LS7 rotating assembly is probably fine I'll keep it for a project or spare. I don't see a point of using it just for the block.

I'm getting married April 14th and the future wife said just don't blow the bank before the wedding. After that is done I'll have an idea of what is left over. If I get a block before then my mom is coming from Southern California in a truck so I'll just have her haul the block out to Steve@RED to save me shipping if that is the route I'm going.

 

My Helms says:

CMP 106 lb in
camshaft retainer bolts 18 lb ft
camshaft retainer bolts Torx head 11 lb ft
camshaft sprocket bolt 55 lb ft first pass, 50 degrees 2nd pass.


Bummer when GM can't get it correct.


Elmer

 

Good luck with the rebuild

 

Could the issue be the dry vs. liquid lock-tite on the bolts? Does the stock bolts use the dry lock-tite?


Elmer