Rust on Intake Cam - 2014, 60K miles

[eap]

This is an expensive repair, found rust and pitting on both intake cam shafts! What can cause this? How to prevent from happening again? The bike has been well serviced and is ridden fairly regularly albeit only twice from new years through Feb 22. Maybe twice in December due to poor weather.

 

[PGlaves]

I have no explanation as to how it is possible to get water or condensation inside a valve cover and for it to cause corrosion of a cam lobe which is supposed to be continuously lubricated with oil.

 

[omega man]

When was the last time you had a peek under the valve cover? This thread may be relevant-

https://forums.bmwmoa.org/showthrea...-prematurely-worn-cam-lobe(s)-in-your-wethead

Let us know how you make out.

Good luck.

OM

 

[windsailor97]

That does seem odd.

Could short running periods result in increased moisture in the engine? (letting the engine run for 15+min may reduce this?)

 

[eap]

When was the last time you had a peek under the valve cover? This thread may be relevant-

https://forums.bmwmoa.org/showthrea...-prematurely-worn-cam-lobe(s)-in-your-wethead

Let us know how you make out.

Good luck.

OM

Last valve check was Feb 2021 at 48K. Bike is about 58K now, so almost exactly 1 yr and 10K miles since last check . No adjustment was needed and no sign of this issue. Thanks for the link!

 

[eap]

That does seem odd.

Could short running periods result in increased moisture in the engine? (letting the engine run for 15+min may reduce this?)

I was thinking along those lines, I road it hard the last 2 times in cold weather then parked it in the garage... Condensation?

Anyway, I have the parts and a buddy and I will replace the cams this weekend.

 

[strataj]

Is that corrosion at the spark plug seal? Did you wash the bike with a pressure washer?

 

[56982]

I'm not a mechanic, but it seems odd to me that the lobes on both intake cams are pitted. as they are on opposite sides of the motorcycle. Is there a possibility that the cams were bad, to begin with? Even though it sounds like they were fine when you did the last inspection. Again, just my two cents. Good Luck.

 

[boxflyer]

It's hard to tell from the second picture, the picture of the LH cylinder, but it looks like the O-ring in the spark plug recess might be missing from under the cam bearing block.

Do you have any other images of the LH side? I can definitely see the O-ring on the RH side, but it could be your point of water ingress that caused this.

If it is missing, you can go back to the last time the cams were removed to adjust the shims and know how long it has been open to water.

I don't think it's missing, because the oil would have been leaking into the spark plug area as well...and I don't see any oil...

Who knows???

 

[oldcamper]

The pictures appear to show deep localized pitting. I think surface rust from moisture vapor would be much lighter and widespread.
I'll guess the camshaft material is somehow defective. This wouldn't be the first BMW M/C with bad cams, after all ...

Sorry to see people are still having issues with this. It's an expensive repair.

 

[omega man]

I think I was thrown off by the mention of "corrosion" (rust, rusty) and noticed the reddish or caramel color (cold synthetic oil) sitting in the various nooks 'n crannies of the heads.
When I focus on just the "galling" of what appears to be the "hardened" lobe surface, it appears to be similar to what many others have reported.
I seem to remember others have received satisfaction on this at BMW's nickel.....make that G-Note. I won't hurt to ask and at least report this to your dealer.
Good luck.
OM

 

[henzilla]

Is that corrosion at the spark plug seal? Did you wash the bike with a pressure washer?

Was my thoughts as well

 

[GTRider]

Bear in mind that the breakdown of some oils can leave deposits that look like rust but are not. DA oils had an issue with that decades ago-the top ends looked like they had a fine coating of rust, but it was surface deposits from the breakdown of the oil. IMHO, for rust to have caused the wear and pitting that’s evident on those cams, they would have had to have been very heavily coated with rust and for quite some time-years, not months.

Hope the repair goes well,
DeVern

 

[akbeemer]

Those cams look like some others I’ve seen that were failing due to improper surface hardening during manufacture.

 

[ramble]

Look like the cams removed from my 14 at 22K. Now paperweights or trot line anchors, expensive ones!

 

[oldcamper]

What are those things that look like little balls of solder along the edge of the lobe?
Also, what is that stuff on the cam end flats, the surfaces used to check alignment?