Concerns for undrilled lubrication holes in NEW OEM Camshafts
 

Make sure to check those new camshafts before installation:

WOW...

That’s insane.

That’s crazy. What’s the fix? Remove valve covers and start drilling holes?

After seeing this I’ll have an even harder time believing that car manufacturers don’t build their product to eventually fail on purpose.

Gosh I just had this discussion about Ford's yesterday and I didn't want to believe it, but God damn

Anyone care to explain please for those of us less mechanically inclined?

The inside of the cam is hollow for oil to pass through. Those little holes are there so oil can lubricate the bearing. If the hole is not drilled far enough, no oil will come through to the bearing.

I’m no lawyer, but if this is found to be consistent across all M156 camshafts, I smell a class-action lawsuit or at the very least a forced recall. It’s a critical design flaw. Even more so than the headbolt debacle.

It's not really a design flaw as the head bolts were.

I would bet my money on that the bit which drilled the holes was damaged and partially broken off and didn't drill the hole deep enough.
If they don't do a flow check and that info isn't traced with the 2D barcode then good luck finding the bookends.


That is just going to be blown off by the manufacturer. Worst case they have to implement a poke yoke in their production step.
At best they will recall the cars if the can find the bookends.

Most likely the camshaft he used are made as a service part by the manufacturer. Which is a non standard set up for them and stuff like that happens all the time.
In that case the original camshafts shouldn't be effected if my theory is right.

I saw zero wear issues on my cams. I think it was mentioned in the vid about it being a problem with new (possibly updated??) M156 cams?

Either way, that's a serious problem lol.

I would love to see their "Control Plan" for this process. As industry standard, they should have higher levels of detection where there is higher chances of occurrence's. Sounds like someone didn't fill out their Potential Failure Mode and Effects Analysis honestly. :bs:

Yes. someone talking the same language.

Definitely missed something or didn't follow something in the PFMEA. Just the potential effect of that failure should trigger a prevention and detection step.

No. For MB to make this right I demand an SLS BS. (going out to car to block cam oil passages now)

Ridiculous, right?!

I truly hope it is small error in just a smaller batch of bad camshafts, likely caused by incorrect drill depth setting.
But a lot of the machining at MB is probably automated, so who KNOWS how many newer camshafts are faulty.
Sven's theory of a possible broken drill bit is also very plausible.
Older camshafts do not appear to be affected.
There are reports of faulty New camshafts appearing in Germany, Australia, & Singapore (comments in Part 2 of this video above).
Then there is the possible issue of planned obsolescence. . .

The mind reels.
And I just had all camshafts replaced with New a few months ago :smash:

I’d pull your valve covers and check those holes with a paperclip. Like, today. :(

Alright!! So I’ve got a ‘09 with bad head bolts but likely OK oil passages in the cams! Yay balance in the universe...

Didn’t some of the ‘09’s come with soft metal cams? :mercy:

yep so replace them with the new ones and hope for oil passages! Yay for quality management

If the oil cant pass thru, it must come out somewhere, so once is installed it wont work right. But how on earth could this happen with MB?

One of the intakes is drilled and the other not? Which side is not drilled through, passenger?

You need to yank the cams to check. The hole is under the bearing cap.

Why not pull the cam bearing caps one by one, inspect, retighten?
I'll take a look at the normal cap reinstallation procedure, to see if the cap-by-cap can make sense.

Meanwhile, i wonder if there is always the same cam that displays this problem.

Taking off one cap for each cam should be sufficient.
The odds are very low that just some of the hole aren’t drilled deep enough.

That would be handy if the holes were all pointing up. I wouldn't rotate the engine with a cap removed.

The clocking of the lubrication hols remains unchanged vs the cam lobes.

The CAD-CAM (excuse the '70's engineering term) of the factory machining rig would always drill for every cam at the same circular angle.
Whatever angle Tassos's video shows (By example the lubrication hole is 30 degrees past the 4th intake lobes), our cams will have as well.

We can take a look at Tassos's video and see the clocking of the holes vs the lobes and assess which way they're facing (the lubrication holes under the cover of the caps) by looking at the lobes of the cams, as the cams sit installed in our cars, with the valve covers removed.