Hey there. In this article. We rebuild a modern GM V6 Engine! (An LLT GM HFV6 to be specific)
But, first off, an apology.
My content has been a little, sparse of late, and I’ll be honest. I’ve been going through a lot.
Super Short version, as to be honest, you’re probably not here for my life story, but.
* I came out as Gay (Thanks, Greig, for your support and well, everything)
* Separated from my Wife of 20 years (amicable split, we are still friends, and we share custody of the kids)
* Massive changes at Telstra, ending in my eventual departure from full-time work and my transition to contracting. (Hire Me)
So yeah, the blog, my YouTube and even UcmPsTools updates have been, lacklustre at best.
It’s not from a lack of trying, either. I’ve started heaps of articles. Only, I never found the drive to finish them.
This article is an attempt to solve that problem by writing something that’s not work-related.
So here it is. The time I went crazy during COVID and rebuilt the engine in my 2010 VE SV6 Commodore.
What Happened?
My pride and joy as we went into lockdown here in Melbourne (we had the longest covid lockdown in the world, by the way) was my 2010 SIDI VE Commodore, and unfortunately, it was a bit of a unicorn.
The Americans in the room may know it as the Chevy SS. It was based on the same platform as the Camero of its era, and even shared engines. Specifically, the GM HFV6 that powers a lot of GM’s vehicles.
Firstly, be aware that I’m going to shed a bit of shade on the design of my particular car at the time. One of my mates actually worked at Holden diagnostics, and we agreed this was a stupid decision.
However, I accept the fault was still mine, and I had no one to blame but myself.
But cmon, Holden. Why didn’t the 2010 VE SIDI have an OIL LIGHT ON THE DASH?
I personally maintain my own vehicles, and up until this event, I didn’t own an OBD scan tool (the computer your mechanic plugs into the car to read what’s wrong).
Especially as Holden didn’t really embrace the OBD2 standard until the VE (2006), prior to that, they used a standard called ALDL, which Holden originally started using in the 80s! (Hey, I know that website… I wrote a guide for them almost 20 years ago!)
This was super annoying as my car had thrown an alert on the dash “Check Engine”, meaning the computer in the car had detected an issue, typically with a sensor or actuator and that it needed to be checked out.
Normally, as I didn’t own a scan tool, I’d take the car to my local parts store, as they offered a service where they would scan your car for a small fee.
But, during covid they couldn’t see me, and the “Check engine soon” message on the display could have meant anything, but it typically means an electrical problem. Not an oiling one… (That’s what the oil light, or “low oil pressure” warnings, are for!)
In fairness to Holden, the VZ (the model before the VE) was notorious for having faulty oil pressure senders, so maybe that’s the reason the VE didn’t have an Oil Light?
Why the unicorn?
Holden had a history of “Tick, Tock” updates when it comes to their cars. Typically, we would see a new powertrain dropped into the last of an outgoing chassis as a “beta test”, if you will, so that a new platform isn’t plagued by both chassis and powertrain teething issues at the same time.
Some examples of this were;
The VL Commodore
Same chassis as the VK with some design tweaks and a new RB30E engine (yes, the same family as the RB26 engine) from Nissan that was supposed to go into the VM Commodore
VM Commodore? That doesn’t exist?
Correct. The VM was supposed to be the successor to the VL. Basically, the Australian dollar went up hard against the Japanese Yen as the VM was in pre-production. So Holden decided the engine would be too expensive and instead, decided to scrap the VM and use what they already had to create the VN Commodore. It was the VM body, but with a hastily modified version of the GM LN3 3800 V6 powering it. It was famous for being a transverse engine stuffed in a longitudinal body, and Holden just added stainless steel/aluminium pipes to route coolant to the right places. Later revisions had new castings made to better suit the layout of the VN, even if it took a few goes.
The VS Commodore
The VS had the same chassis as the VR before it, which also ran a newer version of the LN3 known as the L27. But the VS would get the L36, which was a heavily modernised version of the 3800, known in Australia as the Ecotec) The VS would be a beta test of the L36 for the VT Commodore chassis
The VZ Commodore
This was the last of the Opel-derived chassis, and it got the new GM HFV6 LY7 “AlloyTec” engine, or RattleTec as it became known locally. As a beta test for the VE Commodore. It was a new platform designed from the ground up, instead of Holden modifying old Opel designs.
Okay, Beta testing, sure, but what about yours?
Well, my 2010 VE got one of these new “beta” engines, which was planned to go into the VE series 2.
The series 2 was a mid-model refresh, and was going to get the shiny new Direct Injected LFX engine instead of the Port Injected LY7 and its siblings. The new engine had a whole bunch of new stuff GM was developing, including, as mentioned, Direct Injection, new heads with the exhaust runners cast into the head itself, needing only a single exhaust pipe on each side of the engine, instead of three on each side and a new ECU.
A lot of the features were originally tested in the “LLT” engine that went into my car
* Direct Injection
* Thicker Timing Chain upgrades
* Stronger bottom end
The LLT didn’t get the Monoport heads from the LFX, meaning LLT and LFX’s are NOT interchangeable (you can swap the heads though!)
It should be noted that the timing chain upgrades were to address the “RattleTec” reputation the engine was getting; however, it has been suggested by mechanics far smarter than I that the main issue was a poor PCV valve design and extremely long service intervals compared to the 3800. This allowed oil sludge to build up on one bank of the engine (which you can see in mine!), causing higher friction and thus heat on the timing chains, causing them to stretch and need to be replaced
Knowing about the timing chain issues, I spent a pretty penny replacing all three of them as soon as there was any indication of timing chain wear. I also installed higher-lift Mace Performance cams whilst I was at it. This required an engine retune as well.
What I didn’t know at the time was that this particular engine is known for having oiling issues with the bottom end; one of the oilways gets clogged, and the bottom end spins a bearing when oil pressure is low. (Hey, remember that lack of an oil light?)
And your point is?
Well, the day I was allowed to drive more than 5km from my house because of the lockdown. I went up into the mountains and came down with a knocking noise from the bottom end.
My theory was that bad servicing intervals and all the short drives during covid had filled the oil with fuel, which never got the opportunity to burn off. So once the engine got nice and hot. All that fuel evaporated, lowering the oil level, all whilst I was placing a fair amount of demand on the engine.
This all came together to cause the engine’s failure, and due to their high failure rate and rarity. Replacements are expensive as all get out for a Commodore. (LY7’s could be had for $600… LLT’s were $4000.. with over 200k kms on them when I was looking)
Plus, I’d dropped 4 grand on the chains and cams in this existing engine already. Certainly, there was a way to fix it?
First Impressions
Well, first things first. We knew “something” in the bottom end was gone, but not what.
So off to my grandfather’s farm, where we stuck it up on a hoist, pulled the sump off and inspected the carnage.
For the non-car people, that glitter in the oil is bad. It’s metal shavings from where metal-on-metal contact inside the engine has occurred.
Despite having lots of metal things rubbing against each other in an engine, there is almost always a thin film of oil keeping those parts apart.
This is maintained by oil pressure, so the parts literally float over each other. No oil pressure. No protection
Well, Something’s Very Broken Then!
Yes, yes it was! And it didn’t take long for me to find it either. A spun big-end bearing
Image source: HowACarWorks.com by Alex Muir, go check them out!
Big end bearings are slivers of thin, soft metal, polymer coatings and magic that are designed to keep the Connecting Rod constrained to the Crank until the engine can build oil pressure. The idea being that the soft metal won’t damage the crank when they touch during startup/shutdown/engine knock. When the engine is running, a thin film of oil is forcibly pumped between the bearing and the crank to keep them separate.
These were my bearings when I pulled the endcaps off
And unfortunately, the Crank was damaged too.
The Dodgy
A quick look at the carnage, and it was looking bad. At this point, at a minimum, I’m looking at a lower-end rebuild. With a new crank, new bearings, and I’d be back together in a week or two. Cool, I think to myself.
But this is covid, everything is shut. No engine shops keep this crank in stock, and the ones that will regrind it are asking for $2600! Not to mention that if I’m pulling the crank out, we’re basically in full engine rebuild territory.
So, I did the dodgy, I cleaned up the surfaces as best I could with emery paper, slapped a new set of bearings in and filled it with thicker oil. It only had to last till I had better options.
It lasted 2 weeks.
Join me in Part 2 when I get to the actual teardown and rebuilding of the engine itself.
Coming “When it’s Done” ™