5.7 with Issues

[Fast69Mopar]

So, after about 12,000 miles on this fresh short block I put together earlier this year one of my NOS Mopar lifters started making noise and it never stopped. That is until it completely collapsed at 60mph on Interstate 35 South and then
WHAM-BANG-POW goes the timing chain tensioner. The guide on the left side of the tensioner sheared off and the timing chain got bound up in the commotion and broke the chain. Since the chain broke while driving at 1500RPM I had to contend with two bent intake valves, two bent exhaust valves and a bent pushrod along with the collapsed lifter.

I was really disappointed about how this motor looked inside after a fresh build and 12,000 miles in just under 9 months. The Mopar lifters were a set I had saved back in 2021. The timing gears were from a Mopar set and the tensioner was from a Melling 3-704S set I had in the shop.

I found a ton of oil in the intake manifold and the oil control rings had too much carbon buildup in them.

So, here is the damage...

 

[Randy Grant]

Are the lifters in these 5.7's roller bearing???

 

[Fast69Mopar]

Are the lifters in these 5.7's roller bearing???

Yes, they are roller lifters.

 

[Fast69Mopar]

Now, here are the cylinder heads after a full cleaning/inspection, sonic check of the deck/head surface and two valves replaced in each head. I was pretty disappointed to see these heads get hurt because I have invested over 40 hours into the port work and they flow great. My handy work was worth an extra 37cfm on the intake side and an extra 19cfm on the exhaust side. All flow number were conducted at 28" of vacuum and these numbers were at .600" lift.

I sent my video borescope through the camshaft tunnel to inspect the came bearings and for being original 2006 units they look pretty darn good.

 

[MrBonez]

Hmm...
I'm thinking the amount of cam lift vs the offset geometry of a hemi as it's designed from the factory might be a problem here.

I know you have to be running better than valve stock springs at least and if not, weak springs may also be a cause of problems here resulting in valve float, creating a momentary "Slack" (Hammering) condition occasionally in the valve train when running at higher RPM's during a run, such as the pushrods to lifters, or even lifters to cam lobes.....Maybe all three.

If I understood the reference correctly, .600 is alot of lift for an engine of that size (345CID) so I know what you are using it for, not to mention all the head work you've done says it all anyway.

Maybe a cam profile with a little less lift and a little more duration to compensate may slightly slow down valvetrain movement and do the trick here?

I know that more duration will shift it's powerband up higher in RPM's but to make it "Live", looking into things about valvetrain geometry before rebuilding would be a smart way to go here so maybe it will live longer than just 12K on the clock.

I've had such myself before and the price paid for it is always the same regardless if it's not done right and even if it's done right, something eventually breaking just goes with the territory anyway.

 

[Randy Grant]

Yes, they are roller lifters.

If you had a lifter fail, it was most likely a needle bearing fail. You might look at a different setup with bushings instead, so that you have 100% surface load instead of the very small load surface of the needles.

The main problem with roller lifters is that if the needle bearings fail, they can escape the lifter and cause catastrophic engine damage by getting caught between the piston and cylinder wall. Other issues include excessive wear, noise (ticking or knocking), and potential failure due to aggressive cam designs, high spring loads, and poor lubrication.

Lifter Bearing Options

Brad Miller (BAM Lifters) has been building our mechanical roller lifters for nearly a decade. This video is an excerpt from a Facebook Live at PRI 2024. Thi...

www.youtube.com

 

[Fast69Mopar]

If you had a lifter fail, it was most likely a needle bearing fail. You might look at a different setup with bushings instead, so that you have 100% surface load instead of the very small load surface of the needles.

The main problem with roller lifters is that if the needle bearings fail, they can escape the lifter and cause catastrophic engine damage by getting caught between the piston and cylinder wall. Other issues include excessive wear, noise (ticking or knocking), and potential failure due to aggressive cam designs, high spring loads, and poor lubrication.

Lifter Bearing Options

Brad Miller (BAM Lifters) has been building our mechanical roller lifters for nearly a decade. This video is an excerpt from a Facebook Live at PRI 2024. Thi...

www.youtube.com

Well, the failure on these lifters was that the #1 intake lifter would not stay pumped up. I did not have a roller failure or any damage to the camshaft. I have had excellent service life from the Johnson Lifters in my other 5.7 and I have another 5.7 with the Jeg's lifters with 87,000 miles on it now without a peep from the lifters. It just sucks that this is the first set of Mopar lifters that has let me down.

I have the heads cleaned up and repaired as well as new pistons, rings, rod/main bearings, Johnson Lifters, a new cam, timing set, oil pump, water pump and spark plugs.

This is a 2006 block that has been bored .030" over and with the pistons that were in it the compression ratio was at 10.87:1

The new pistons going in the block tomorrow are a set from DSS Racing that came off-the-shelf from Summit Racing in Arlington, TX that should yield a CR of 10.81:1 with the head gasket I am using.

 

[MrBonez]

Good to hear there were no signs of further/extra pending failure with other parts so it looks like your setup (Minus the defective lifter) was good overall.
Sometimes it's like that - Been there, done it all before myself.

 

[Fast69Mopar]

Good to hear there were no signs of further/extra pending failure with other parts so it looks like your setup (Minus the defective lifter) was good overall.
Sometimes it's like that - Been there, done it all before myself.

This truck is actually my nicest and cleanest 3rd Gen being a 2006 QC Laramie. I bought this truck with a hurt 5.7 from a local farmer who used it as his truck to take to town. He kept it in really good shape and after the motor got hurt they parked it indoors and it sat for two years before he decided what to do with it.

I build quite a few HEMI's a year and I had one ready to go when I bought the truck. I'm glad this is the only damage that was done when the tensioner broke and the timing chain broke. It's a simple fix. The only parts I had to buy were the pistons and rings and the only reason I changed the pistons after 12,000 miles is because I found a stuck oil control ring and I got the pistons at a crazy price. I was really just looking for an excuse to go to Summit Racing and spend some money.

I'll have this 5.7 put back together this afternoon and in the truck. I hate working on my own stuff after something breaks. I'd much rather build cool, new stuff and do upgrades.

 

[TimboRam77]

It pays to have skills

 

[Fast69Mopar]

It pays to have skills

I worked as a mechanic for Chrysler and Cummins for 25 years so working on the 5.7's and 6.1's I have is easy peasy.