Cams have been going flat ever since the car engine came out, however today it seems to happen more often. I blame the cam companies for putting out radical cams that open and close the valves too quickly and calling them mellow. The last cam I installed was in a Oldsmobile 400. The owner never opened the engine up but he flushed the oil galleys out with cheap dollar store 5W10 oil and Rislone..
2OLD2FAST, You still can't just put them on for just breakin and not refit the engine with the correct length pushrods to center the rocker tip on the valve stem. You'll damage the end of the valve stem running the tip off center.
Oil filters can only catch the larger particles, and what gets through them is still going to be able to cause premature wear inside the engine. Plus the bad camshaft particles can do damage to some areas before they reach the filter to be recycled throughout the oiling system. The typical stock oil filter catches particles of around 25 microns. Some more expensive filters, or secondary filters catch smaller 10 micron particles.
Just to clarify, a 25 micron particle you would not be able to see without magnification. Maybe if you have excellent above average eyesight. 10 microns? Forget it, not visible to the naked eye. If they are too small to be filtered, they are too small to be seen by the naked eye. If they are visible in the oil pan or in the bearings or elsewhere, they are large enough to be captured by the filter.
Filter/no filter, you've still got metal particles being thrown about by the reciprocating assembly. All my damage in my case was in the cylinder of the damaged lobe and the one across from it. In other words, not pumped through the oil passages, but flung on the cylinder walls as it drained off the lobe/lifter. One cylinder is trashed.
A line mechanic also mentioned the cam anti walk button solution. This was taught in mechanics seminars, keeps the cam from walking so the lifters can properly rotate in their bores. Zddplus is an Alliance Vendor here. There is good information on their site about low levels of ZDDP in modern oils.
Sorry about that but I see someone has posted it in the other thread about cam failure thread about BBC cam failure .
The ratio change is at the pushrod end of the rocker arm, fulcrum to valve stem stays the same. If going from 1.6 to 1.3 the push rod would be about .100 farther away from the fulcrum.
We're seeing a fair few flat tappet failures now, most caused by soft lifters. We got this reply from a leading camshaft company after following up on a failure: The camshaft hardness is the same from one end to the other, so to lose a few lobes & not all indicates a break-in issue. Same way with the lifters. Appears the customer & (camshaft manufacturer) did everything right, but this still can happen from time to time. Never have been able to figure out why it happens even after inspecting the cams & lifters. It could be variables within the engine set up or valve-train geometry but there isn’t a rhyme or reason why when everything was made & installed correct. I know of a couple of engine builders that only install roller cams now days Not that they had on-going issues with flat tappets, it’s just when one goes down and by the time they buy another cam & lifters, the cost for sets is what a roller set up would have been. So to eliminate the rare case of it happening, they install rollers. Don’t know if this helps, but this is one of those thing that can happen like a wheel bearing going out way before its time. If you want to replace the cam & lifters with the customer, we will issue a good faith field destroy credit. Pretty piss poor response in my opinion
Let’s beat this dead horse one more time.. I’m close to firing up a brand new SBC. As we all know I’m that one guy that didn’t get the word about lack of ZDDP in modern oils will eat your cam. Sorry, but I don’t rebuild regularly, only after some brilliant oil engineering changes that completely change the game. So here’s a tidbit to the other guys out there someplace that also missed the ZDDP memo. The break in procedures provided with a brand new flat tapped engine NEVER MENTION this issue. It simply says to use 10w30 (non synthetic). Odd, in that the engine comes with a two year warranty. So if I follow their break in, and thrash the cam, it falls under warranty. I’ll attach a pic of the procedure provided with the engine, which oddly enough bears a remarkable resemblance the the procedure I used prior to my cam fiasco.
When I called LUCAS they told me to buy Lucas Break in oil about 2 oz. when I change oil work's good So I am Protected, now I noticed that they are selling oil. Mabey the next time go the parts Store I check it out. Just my 3.5 cents Live Learn & Die a Fool
I have a similar GMPP engine...a 350 HO made around 1995...never fired. I'm thinking...and really hoping, that GM crate motors are spun on a fixture that breaks in the cam and starts the ring seal. I can't imagine how many engines would lose cams on first fire up by people who don't know what they're doing. Seems like cheap insurance for GM to spin these motors and make sure they're good to go. A local machine shop offers that service as an extra on their rebuilds, im sure hoping GM did it.
Lol,,,,,I like the high lighted portion of the instructions with the crate engine . Uses an aggressive flat tappet camshaft,,,,,,.450 lift intake,,,,.460 lift exhaust. That’s a good one . I guess the factory guys wanted to make sure to warn everyone. Tommy
The guy who bought my crate motor from Chevy also bought a new cast iron q jet manifold for it if you can believe that. Cost him nearly $300 in 1995 dollars. I'm gonna swap it out at some point for an Edelbrock, and when I do...ill have a look to see if there is assembly lube on the cam or lifters...or any sign of wear on the cam for that matter. If there is no assembly lube, it was spun like I hope....if there is lube, then it wasn't. I'll report back...but it might be months sadly.
AGELE55, I can understand why you'd get confused with Chevy Performance start up sheets not mentioning any special oil or additive at all. And I'm wondering why they wouldn't mention special higher zinc level oil too? Seems they're leaving themselves wide open for a warranty return if a buyer didn't heed the advice of almost everyone else about using the proper flat tappet oils.
I’m curious . With all of the post about cam failures lately,,,,,,why don’t the crate engines eat cams ? You would think that would be a prime candidate ? Any ideas ? Tommy
I wonder why engine builders don't brake in new engines like the factory's do. They hook the new assembly to an electric motor and spin it while watching the piston and camshaft braking in.. There was this old mechanic down the alley from me that connected this home made electric motor up to the new engine block with out the heads installed. He would watch the pistons brake in while squriting oil all over everything using a Rigid pipe threader oil gun. Then install the heads, push rods, lifters and run the engine again while watching it all brake in. Never once using combustion to spin the engine. I think running a brand new engine by it own combustion puts a lot of un wanted stress on the new parts. Has anybody here ever seen this process? V8 ENGINE - Car Factory Production Assembly Line - Bing video
If the crate engine was built prior to '97, no special oil was needed, the oil formulas didn't start changing till '97 and later.
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