Changing oil...Let it drain overnight ?

[Fully Vetted]

Originally Posted by Dynomite

This is what Canton Racing says about their Accusump System.
I am no so sure about the wear and tear when I start
I would think if this were a serious problem, GM would have incorporated a Pre-Oiler system

Did you know that most of the wear and tear on your engine occurs when you start it? Solve this problem by installing an accumulator, which is also a pre-oiler! By circulating oil throughout the engine before you start it, you can avoid the damage caused by dry starts! You'll also get added benefits: You'll increase your oil supply and, because the oil in the accumulator is under constant pressure, if the oil in the pan runs away from the pick-up durring hard cornering, the oil in the accumulator will continue to lubricate the engine! You'll be double protected. It's a huge return for a small investment.

I am thinking of installing this.....

Cliff - I just came across my dad's entire collection of his oilers. And they are all Lunkenheimers and beautiful!

[Paul Workman]

Sitting here sippin my coffee, I just remembered that story from the HOTB book, where this gal was cranking up the brand new ZR-1s in sub freezing temps with the accelerator nearly floored. The result was a number of new ZR-1s with cam failures. So, it seem a quite plausible notion that most of the wear over time goes hand in hand with cold, dry starts, sans pre-oiling.

I too crank my Z every 3-4 weeks when in winter storage. My thought is to minimize the "drying out" of the bearings, and keep fuel residue from gumming up in the injectors (which actually happened to one of my motorcycles and a pressure washer left too long over winter w/o running). Pulling the injector fuses, IIRC, is easy to do, and would allow some pre-oiling/cranking for say 4-6 seconds w/o worrying about it firing up. (If it does fire, one would have to be wondering about a leaking injector.)

I knew this discussion was going to veer into something useful!

[Dynomite]

Originally Posted by Paul Workman

this gal was cranking up the brand new ZR-1s in sub freezing temps with the accelerator nearly floored. The result was a number of new ZR-1s with cam failures. The result was a number of new ZR-1s with cam failures.

Now you are scaring everyone.......

cannot tell what is meant by cam failure.

Was it due to gas pedal to the floor, freezing temps, or a brand new ZR1 that had sat for months on show room floor
Or.......something else entirely??

This discussion has just veered into something scary

[A26B]

Originally Posted by Paul Workman

Sitting here sippin my coffee, I just remembered that story from the HOTB book, where this gal was cranking up the brand new ZR-1s in sub freezing temps with the accelerator nearly floored. The result was a number of new ZR-1s with cam failures. So, it seem a quite plausible notion that most of the wear over time goes hand in hand with cold, dry starts, sans pre-oiling..................

That's just part of the story.

As related to me by Graham Behan.
Upon investigating this problem, it was discovered that the cam journal & corresponding journal bore tolerances were at fault, but certainly exacerbated by the starting procedure. All machining dimensions have tolerances, or a range of acceptable size. The size usually varies from tool wear and the machine tool accuracy. Such is the case here. As it turned out, clearance from the cam journal diameter at the large end of the tolerance and the journal bores at the small end of tolerance was insufficient. Revising the dimensions & corresponding tolerances solved the problem, right along with the cold start procedure.

[A26B]

Originally Posted by Dynomite

WEW......Thanks Jerry......was about to start tear downs of five or six LT5s to investigate the issues

It appears this was then a problem in the design of the first few LT5s that has long been corrected.
It also appears that such failure was not a locking of the camshaft between the cam covers and head but just a lot of initial wear of aluminum in the cam cover and head where the cam shaft was in contact. Or was this something more catastrophic????

I have noticed that on all the cam covers I have removed that some cam cover journals on the same cam cover have greater wear than others.

I have also noticed that the cam cover journal wear in general is the same on ALL cam covers no matter how many miles on the LT5.

This indicates some intolerance from the get go in the design of the cams/cam journals which seems to correct itself (quickly) by the wear indicated. In other words, once worn in the wear stops and the cams find themselves in a comfort zone for thousands (100,000 or more miles).

I am assuming that ALL the LT5s that came off assembly line with this initial Cam Journal intolerance were corrected in a call back??

And....what is the Cold Start Procedure??

About the wear pattern in the cam cover/cylinder head journal bores & similarity in different engines.
Think about the forces on the camshaft along the length of the cam. I think you will come to understand the wear pattern & why it is the same in other engines.

[A26B]

Originally Posted by Dynomite

Once in a while one will find aberrations in components like the Cam Lobes on one camshaft I found where there was wear on one side of the lobe as if the cam lobe was not cut parallel to the lifter (every lobe of that camshaft).

Supposed to be like that to impart rotation of the lifter.

[Paul Workman]

Sorry If what I said about WOT cold starts scared ya Cliff - or anyone else. I recon my point was missed; no fault of yours or anyone's (and I DO do cold starts, all winter long, FWIW).

My point was only with regard to when some reports say significant amounts of the total wear occurs in any engine, i.e., during cold, near-dry starts in general. The LT5 WOT cold start affair was (to me) just a bizarre & extreme example of such damage of cold and perhaps dry starts. And, Jerry brought additional info regarding the particular circumstances that further exacerbated the net result - further insulating us from actual wear and tear.

I guess we're past the age old question that started this: Does your chewing gum taste better left on the bedpost over night? (Or was it oil draining over night? - I forget: seems so long ago!))

[5ABI VT]

Changed my oil today.. I did let it sit overnight tilted to the drain side. I also did fill the oil filter up and let it sit and soak in for 2 days.. tipped it over to let any excess oil out and then screwed it on. I warm my oil up in the oven .. pours like water and figure couldn't hurt startup when its cold. the 10w40 is like ketchup compared to when its warmed up.

[Fully Vetted]

Wow. Just...wow. Ok, you win.

[RussMcB]

I've found that if you play soothing music to your oil for two hours the night before it flows into the engine better.