01-16-2021, 06:01 PM | #1 |
Private First Class
33
Rep 119
Posts |
X3 F25 camshaft pattern
Replaced the valve cover gasket on my 2017 X3 3.5i and saw this pattern on the cam lobe. Wondering if this is normal or sight of abnormal wear.
|
01-17-2021, 09:33 AM | #2 |
Lieutenant Colonel
800
Rep 1,895
Posts |
Looks unusual; have you had any issues in past with how the motor runs? (valve clatter, misfiring, etc.)
How many miles on the car? See pic, unfortunately camera not focused properly but as I recall the lobes on my car's camshaft (this is actual pic at 85K miles, N52 motor) were very smooth; certainly noting like what's shown in your pic. Last edited by Wgosma; 01-17-2021 at 12:08 PM.. Reason: add pic |
Appreciate
0
|
01-17-2021, 11:31 AM | #3 |
Major
626
Rep 1,044
Posts
Drives: 2018 X3 M40i, 2012 X3 Xdrive35
Join Date: Aug 2012
Location: Moraga, California
|
I replaced my valve cover last year and didn't notice those lines. Wear lines would obviously run parallel to the lobe. They look like original machining marks but I would think they would be polished by now. Can't help. Sorry
__________________
2016 Z06 Vette, 10.53@132
1984 Vette, 406, 10.23@131 2021 SQ5 |
Appreciate
0
|
01-17-2021, 12:01 PM | #4 |
Colonel
868
Rep 2,527
Posts
Drives: Z4MC-X3-35i-525i, Corrado G60
Join Date: Nov 2007
Location: MD
|
I've seen a lot of cams but have never seen one with those patterns. Is every single lobe like that? Can you feel them with your fingernail. Really strange
|
Appreciate
0
|
01-17-2021, 01:58 PM | #5 |
Private First Class
33
Rep 119
Posts |
Every single on was like that. The feel of the lobes is absolutely smooth. The engine runs great and has 62k miles on it. Will be doing an oil analysis ASAP to see if there is metal in the oil.
|
Appreciate
0
|
01-17-2021, 02:06 PM | #6 |
Colonel
868
Rep 2,527
Posts
Drives: Z4MC-X3-35i-525i, Corrado G60
Join Date: Nov 2007
Location: MD
|
I doubt anything in valve train caused that pattern. I'd think the cam spins way to fast for something to cause it. Maybe it's a newer machining method from the factory to improve oil lubrication
This is a new one for me and I'm curious to know the answer. |
Appreciate
1
Wgosma799.50 |
01-17-2021, 02:09 PM | #7 |
Private First Class
33
Rep 119
Posts |
Upon further analysis, this might just be the original forging lines of the metal. The pattern continues even on the edges of the lobes, the part not in contact with the lifter arm.
|
Appreciate
2
Wgosma799.50 tracer bullet2295.50 |
01-18-2021, 12:01 PM | #8 |
Second Lieutenant
290
Rep 236
Posts |
Looks like forging striations to me. Shouldn't have them but I don't believe you are going to see longitudinal stress that would cause the camshaft to "lengthen" and separate. We need a metalurgist to comment to be certain but I doubt an issue.
|
Appreciate
0
|
01-18-2021, 12:41 PM | #9 |
Check out my Youtube @n55david!
1288
Rep 3,502
Posts
Drives: 2017 m240i, 2015 X3 x35i
Join Date: Aug 2018
Location: Michigan USA
|
nope, looks fine
__________________
2017 m240i xDrive 10.99@122.86mph bootmod3 stage 2+ ots
2015 335i xDrive 10.95@124.99mph w/bm3 - SOLD 2015 X3 x35i pwg 12.96 catless w/bm3 stage 2 93 ots IG: @n55david For pics and updates! Youtube: @ n55david For videos or Racing etc |
Appreciate
0
|
01-23-2021, 05:00 PM | #11 |
Private
29
Rep 83
Posts |
I am not an engineer!
Looking at it it would seem that the pattern, although smooth to the touch, is? ground that way to serve as micro oil galleys?
|
Appreciate
0
|
Post Reply |
Bookmarks |
Thread Tools | Search this Thread |
|
|