Here is my Cheap Febi Cam at 45000 miles.

James & Son

Veteran Member
Joined
Oct 10, 2008
Location
Maryhill, Ontario, Canada
TDI
2006 Jetta
3 years ago I bought the cheapest Febi cam I could find on the internet. It was going to be my 3rd cam.

The first Oem cam was replaced under warranty and had a dubious history of oil changes although 5w-40 505.01 was used.

The second Oem cam was showing wear on both #1 and #2 exhaust follower at 21000 miles and I kept that cam going to 87000 miles by replacing followers on #1 and #2 exhaust 3 times and 3 and 4 exhaust twice. The key was to replace the followers before the black coating wore thru on the follower or the cam lobe would gall and tear metal from the exposed follower metal.

From my experiance with the followers and other members observations in the cam debate years mostly between 2009 and 2015, I decided that if the black coating was key to getting the cam to 100,000 miles and if it was worn through to quickly it would create a surface that the cam lobe oil film would not form on( fracturing from lobe contact stress). This is where the theory of the wear dot as developed by eddif comes in.

I decided it was absolutely critical to get the cam to pass through this center black wear thru unscathed and the new steel wear surface exposed would now work with any oil since it would be steel follower on steel lobe which all oils are designed for.

Here is my #1 exh. lobe at 45000 miles. I took 4 pictures, 2 with flash 2 without and slightly different angles to show the oval contact. It is very hard to get a quality picture of the lobe due to glare.

https://imgur.com/a/WS9hX44

I really don't know how to use imgur. This link is of a post i started accidently i guess. Anyways I hope you can see the pictures
 
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James & Son

Veteran Member
Joined
Oct 10, 2008
Location
Maryhill, Ontario, Canada
TDI
2006 Jetta
These are pictures of followers from my second cam. Note the damage. When I pulled the cam the lifter had center black coating worn away and metal galling.





Here is what the follower looks like. Note the black is worn away and galling. The fracturing of the coating causes the galling. This is from a poorly ground OEM cam that took to long to breakin. With what I know now this cam would have worked if I had prepared it with about 3 to 4 hours of massaging by honing the 45 degree chamfer edge and using 800 to 1500 grit sand paper and sanding across the lobe surface. This would have allowed the necessary quick breakin with out black transferring to the lobe caused by an excessive roughly ground surface.

The black transfer acts as a solid lubricant and does not allow proper break in and the excessive wear of the hard black coating causes the softer steel underlay to score and gall at break thru. This is due to the fracturing coating surface not supporting the oil film development and thus instant galling.
 
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James & Son

Veteran Member
Joined
Oct 10, 2008
Location
Maryhill, Ontario, Canada
TDI
2006 Jetta
It is Victoria Day in Canada and so I am going to take some time to redo my #2 post.

The pinnacle of the cam issue or debate was for me, 2012 to 2015. Colt and Franko6 between 2010 and 2011 began supplying cams since cam failure at this time was peeking.

Two improvements they provided was a properly ground cam with a 4 micrometer rma(root mean average) finish and a phosphate( edit: manganese sulfate( parkerize) coating. Also they are using a better quality( with hardness of 62 RC) after market billet cam for the basis to grind their overlay profile.

This has proved to solve the cam issue. Issues would have come to light by now.

So if you don’t want to pay the money to get a guaranteed cam. What to do?

I suggest you understand what the where dot problem is and what causes it. There is some interesting information for those who like problem solving
http://forums.tdiclub.com/showthread.php?t=368673
http://forums.tdiclub.com/showthread.php?t=443213
 
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James & Son

Veteran Member
Joined
Oct 10, 2008
Location
Maryhill, Ontario, Canada
TDI
2006 Jetta
Lobe Taper:
From my checks and from a few others posting involved with the colt cam. I have taked about lobe taper. I apprieciate Frank's openess by going back to his cam grinder to confirm that likely all cams if following OEM specifications should have lobe taper.

The lobe width is 13 to 13.5 mm and after the 45 degree chamfers are put on the actual width is 12 mm. The follower dia. is 35 mm on the negative side and the follower bore will be on the plus side allowing for a slip fit and manufacturing tolerances.

The overall length of the follower is 26mm, but there are small 15 degree chamfers top and bottom and the actual contact length is 25 mm.

New followers basically seem flat across the 16 mm center area with some very slight tapering(crowning) towards the 35 mm dia. outer top surface.

The cam lobe across the 12 mm width has a taper and I have measured anywhere from almost flat .0003 to .0007 inches or .076 to .018 mm.

Now you have to ask yourself, is it possible to have edge loading during break in. I say yes and that is why I am suggesting honing the 45 degree edge to prevent shearing of the black surface coating. Now a parkerized cam may not have this issue due to the sulfate coating being quite thick and hard enough to reduce the initial edge loading.

Follow the links, to confirm the information on cam taper.
http://forums.tdiclub.com/showthread.php?t=440514
 

James & Son

Veteran Member
Joined
Oct 10, 2008
Location
Maryhill, Ontario, Canada
TDI
2006 Jetta
I want to add a post on oil.

http://forums.tdiclub.com/showthread.php?t=472383
http://forums.tdiclub.com/showthread.php?t=154548&page=231

You can also Google; High oleic lubrication oil

Oleic is a natural boundary lubricant, often referred to as lubricity additive.

My car averages a lot of low rpms ( below 1800 ). I also felt I needed more than normal start up protection. I felt I needed a 5w-40 oil with a high velocity index( 185 VI) and the natural boundary protection of high oleic vegtable oil (a content of 30%) and PAO base oil. I did not want any boron or molydtc. Boron in small amounts as a detergent is ok but definitly no molydtc as it breaks down to mo3 which is abrasive in long life diesel oil.
 

James & Son

Veteran Member
Joined
Oct 10, 2008
Location
Maryhill, Ontario, Canada
TDI
2006 Jetta
Here is a typical science study of cam shaft and follower wear. Note the following conclusions.

http://opac.vimaru.edu.vn/edata/E-Journal/2005/Wear/Vol160is1-2/bai 23.pdf

"In addition, the calculation methodology results revealed that the minimum film thickness value should not be less than 0.2 micrometers under boundary lubrication regimes. This could be achieved with proper cam design, by using good quality lubricant and improved machining process of cam and follower."

This paper concludes boundary lubricated contact at the nose of the cam is inevitable. It therefore makes sense if .2 micrometers is the determining factor, highway driving averaging over 1800 rpm verses non highway driving averaging under 1800 rpm will have an effect along with lubricant and a properly profiled surface and finish.

I believe both colt cam and franko6 used the results of A5INKY ( ref. link below) and switched to a reground billet cam and move away from the cheaper cast steel( oem and after market) to make sure there was enough hardness depth for their regrind.

http://forums.tdiclub.com/showthread...=367003&page=2

Since a cheap aftermarket cam has enough hardness if not reground then it's deficiencies must be addressed which is poor surface finish and chatter marks. That is why spending the extra 50 bucks to get the billet cam is definitely worth while as it it is hoped that it is ground better. Once you have your cheap cam you need to plan every step out carefully.

At about 75000 miles I believe my cam will be through the black follower coating and I will be checking to see if the steps I have taken have proved successful.
 
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