Camshaft and rocker arm has pitting


#1

I pulled apart my Head today,

I noticed some pitting on some of the cam lobes and on the rockers,

What amount of pitting is too much?
There any many things that could have caused this.

Since this car is fairly new to me and has ~200,000 miles on the clock, i am not worried how it they got there. I am guessing it came from the PO as the car was sitting and not running for an unknown amount of time.

I just want to know if ANY pitting is acceptable. I really don’t want to put $ 400 dollars for new Cam and rockers unless I have too.

here are some shots of the worse ones.


#2

Two problems…first and foremost…oil pressure, or lack of. Second, wrong oil…not enough zink and probably too light of weight. Chuck


#3

Chuck,

Thanks for your feed back, I am not looking for a cause of this, I am looking for opinions if this is bad enough to have to replace it. Just rubbing your finger over it you can’t feel anything, but a finger nail catches on it.

The more I look at it the more I am thinking to just replace it all.

Thoughts?

Anyone have a good head that want to sell? source for a good head? or good price on parts?


#4

This is caused by bad oil choices. Our heads have strong valve springs on the order of 170lbs/in. That’s a fair amount higher then later model 4 valve heads. Many modern oils don’t contain enough anti-wear agents in the additive package to protect top ends with strong valve springs. The most common anti-wear additive, as Chuck mentioned above, is ZDDP.

The cam lobes and rocker surfaces are hardened. Once they start showing wear, I’m told that the wear accelerates. This becomes a performance problem too, because worn cam lobes open valves late and not enough. Chuck has an outfit that can repair cams for <$150 or so. New cams are available for $250ish.

Can’t repair rockers, they need to be replaced.

I’ve pulled apart ~8 heads in the last couple yrs. Most had worn out cams and rockers. The only one that was really cherry, was our Lemons car.

My suggestion would be to send the whole head to Chuck and ask him to just make it all right. You’ll end up with terrific work for less then it would have cost for anyone else to do it. You cam will be cherry and your rockers will be polished for better fatigue life. Hopefully you won’t have to buy all new rocker arms, that would be pricey.


#5

Ranger wrote:

9.3.1.2.7. PROTEST!!! Looks like I will be able to move up one spot this weekend. :wink:


#6

Is there anything wrong with the FEBI one that pelican sells?
http://www.pelicanparts.com/bmw/catalog/shopcart/BE30/POR_BE30_ENGcam_pg1.htm

For 172.00 seems like a moot point over having Chuck try to bring my old one back to life


#7

Steve D wrote:

[quote]Ranger wrote:

9.3.1.2.7. PROTEST!!! Looks like I will be able to move up one spot this weekend. ;)[/quote]

so you’re already conceding defeat?


#8

The pitting is caused by corrosion. Probably from the engine sitting for too long. I would say its fine. The pitting may cause it to wear a little faster but it shouldn’t cause anything catastrophic. Until you start losing valve lift from lobe wear you won’t lose any power either.


#9

Get the new cam…good price, too. Also replace all the rocker arms. Label the arms so they can always be installed on the same lobe during any disassemble.

Pitting can be caused by corrosion but if you look at the cam bearing surfaces you will see lack of oil pressure. I would suggest a Paul Poore pan when reassembling. Chuck


#10

turbo329is wrote:

I disagree. Look closely where the pits are and consider where the friction is greatest on the cam and rockers. The visible wear isn’t any ol’ place, it’s in the high friction locations wear anti-wear additives are critical.

Cam lobes and rocker working surfaces undergo some kind of surfance hardening treatment. Once it is worn away, the metal wears quickly. So visible wear accelerates. Ask Eric Nissan about the aftermarket rockers he bought a couple yrs ago where they goofed the surface hardening. He wore right thru them.


#11

Steve, blueprinting to factory spec involves removing the casting flash line on the rockers. If the line is there, you are non compliant:huh: CB


#12

cwbaader wrote:

Where in the shop manual does it… Oh never mind…


#13

I think I have a stock cam and rockers. LMK if you’d like them. $125 for everything if they’re all in good shape (I’ll double-check and send you pictures if you want). Shoot me an email to anthony.magagnoli at tema dot toyota dot com.


#14

Z3SpdDmn wrote:

If they don’t show wear, that’s a good deal.


#15

Anthony, email sent


#16

I’ll get you pictures this weekend.
Ranger says I’m not charging enough, though, so we’ll have to discuss that :wink:
JK! JK! :laugh:


#17

Dan, did you get the pictures I sent last Sunday?


#18

Just sent you an email.

I am in the middle of figuring out if I am going to move to Cali or not. if someone else needs them they can have them, because there is a good chance they are gonna sit in a box for a few months. If no one needs them I will take them.


#19

Peakracer.com wrote:

[quote]Just sent you an email.

I am in the middle of figuring out if I am going to move to Cali or not. if someone else needs them they can have them, because there is a good chance they are gonna sit in a box for a few months. If no one needs them I will take them.[/quote]
If they don’t show wear I’ll take them. Send pics and Paypal pls.


#20

Scott, I just want to get confirmation from Dan that he’ll let you have the cam. Email me at Z3Spddmn@aol.com though so I can send you the pics.

Thanks,