BHW: Excessive cam wear?

Franko6

Vendor , w/Business number
Joined
May 7, 2005
Location
Sw Missouri
TDI
Jetta, 99, Silver`
Now, the rest of the story...

We know something has changed with the cams. For one, we would equally buy Kolbenschmidt as Febi, made from the same Turkish company, until just about 4 years ago we got 'blue boxes'(KS) instead of what we expected, 'red ones'(Febi). The Kolbenschmidt cams we got were marked 'Made in China' and hardness checked 44rc on lobes and 20 on the journals, instead of 58-61Rc. To tell you honestly, we have no idea what AMC was doing at that time, because we only bought a single cam for our test.

As I stated in an earlier post, within the last few months, both KS, once again, and Febi are selling PD cams with boxes marked, 'Made in China'. There are still cams from 'old stock', which we have purchased from Febi or KS. To date, I am refusing any marked 'Made in China'.

The rules that US companies must (atually, are supposed to...) abide by is at least 51% of a product must be US manufactured before the claim 'Made in the US' can be on the product. But I will stand on my judgement, if AMC would pretend to have Spanish-made cam once, would they purchase from China, same as KS and and Febi, but still say it's made by AMC? Maybe... maybe not.

What do you think?
 

d0u8l3m

Veteran Member
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Jun 16, 2014
Location
Connecticut
TDI
B5.5 Passat
Definitely appreciate the info you've shared. I would love to compare one from iDParts to see if they are identical, seems likely.

Side question then, where are your cams produced and why is there no specific BHW profiled cam? Wouldn't you lose a bit of performance with less lift?
 

Kravt

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Joined
Jul 31, 2018
Location
Dayton, OH
TDI
2005 Passat
Definitely appreciate the info you've shared. I would love to compare one from iDParts to see if they are identical, seems likely.

I will be getting a camshaft from iDparts sometime in the near future. I can post similar pictures and measurements to compare. I could even do surface roughness measurements/microscopy if that would be of interest.
 

d0u8l3m

Veteran Member
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Jun 16, 2014
Location
Connecticut
TDI
B5.5 Passat
I will be getting a camshaft from iDparts sometime in the near future. I can post similar pictures and measurements to compare. I could even do surface roughness measurements/microscopy if that would be of interest.
Please do!
 

Franko6

Vendor , w/Business number
Joined
May 7, 2005
Location
Sw Missouri
TDI
Jetta, 99, Silver`
The BHW cam is as available as a BEW piston... it's not. However, the cam lobe shape and height is exactly the same for every single aftermarket stock PD engine. The difference is in the injector lobe height. So, your goal is to find a cam that is either the 038 109 101r or 101ah. We personally, prefer the R version in the BHW engine.

The thing I expect with AMC is that they change and do not necessarily tell it like it is. They have changed before and will change again. When you shop the International Market, what you bought 6 years ago, changed and then they appear to have hidden the truth about the source. It will happen again.

6 years ago, when Kolbenschmidt figured out they got a bunch of Chinese soft cams, I wonder what they did with them? The Chinese are notorious for reselling bad parts to the unsuspecting. Maybe China rebranded the KS and instead imprinted AMC. It's dispicable what happens out there... But about 2-3 years ago, the AMC cam was showing some exceptionally short life expectancy. Maybe the 44Rc cams came to bite them.

Some of what I say is speculation, but I stand behind my statement, when two cams look identical and the truth is at best, dubious, I will state the obvious.

Kravt,

You want to avoid problems, the FIRST thing you do is get the cam designed for the job. Hydraulic lifters... hydraulic cam design. So, since that's appears out of the picture...

You want to check out a cam? Check the cam for the following:
1. Chamfer cut wrong. Assuming the cam was 112mm wide, average. A chamfer that is 9mm like we have seen, takes it down to 111mm. Some lobes are 105mm wide. We have seen aftermarket cams after chamfer reduction were down to 92mm. The less cam lobe width, the greater the wear and the earlier the failure.

2. The profile is cut wrong. The fix is a slight arc in the ramp to the top of the lobe. Aftermarket does not do this. You probably will not do this either.

3. Poor RA, which should be 3-4. Close inspection on many aftermarket cams show chatter. This chatter must be worn off smooth, before the cam/ lifter interface will work well. In the mean time, you are beating your cam followers to pieces.

4. Rc 55 is below grade. Our cam grinder has a non-invasive hardness tester. Without damaging the cam, they can inspect hardness of the cam lobe, base circle and journal. We reject soft cams. Correct is between Rc59-61. Journals are supposed to be the same hardness, but we chrome-plate for smoothness, heat transfer and Rc75...harder than stock.

5. Look for casting marks on the sides of the cam, as this in today's market indicates an inferior cam. The cam should show machined surfaces throughout, with a high quality finish.

6. The cam, when struck, should ring like a bell; just not a cow bell. That would mean it's at very least, cast steel, not a cast iron 'cow bell'. Cast iron is relatively popular in Europe with some vendors, but not here.

You want to go price-conscious? Here you go...It looks a lot like the cams we have talked about. The bearings, lifters and bolts are stated as OEM. Save $$$.
https://www.ebay.com/itm/VW-Volkswa...a=1&pg=2060778&_trksid=p2060778.c100290.m3507

Includes a 1-year warranty, which is better than most. Although I recently found out, if I sell this same cam in Kolbenschmidt brand, it's a 2-year, 24,000 mile warranty.

Choices...
 
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Kravt

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Jul 31, 2018
Location
Dayton, OH
TDI
2005 Passat
4. Rc 55 is below grade. Our cam grinder has a non-invasive hardness tester. Without damaging the cam, they can inspect hardness of the cam lobe, base circle and journal. We reject soft cams. Correct is between Rc59-61. Journals are supposed to be the same hardness, but we chrome-plate for smoothness, heat transfer and Rc75...harder than
Is that a Microhardness tester that they used? If so could you tell me what the force of the test was? It varies depending on desired indent size.
 

blazen71

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Joined
Oct 25, 2011
Location
Wiskullsin
TDI
All Gone
Is that a Microhardness tester that they used? If so could you tell me what the force of the test was? It varies depending on desired indent size.
If the test is non-invasive, there won't be an indentation size.
 

Kravt

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Location
Dayton, OH
TDI
2005 Passat
True! I was thinking it might be small enough to blend in to the surrounding surface roughness. However if that were the case the values wouldn't accurately reflect the hardness due to that roughness.
 

Franko6

Vendor , w/Business number
Joined
May 7, 2005
Location
Sw Missouri
TDI
Jetta, 99, Silver`
The electronic testers are very accurate in the proper hands. That goes with anything, really. Non-invasive like an MRI; see without cutting. It does require a non-parkerized, smooth surface. The parkerizing is very soft and distorts the signal.

The electronic devices emit a ultrasonic frequency. The hardness will resonate and that's it's harmonics. Comparing results with more typical hardness measuring equipment will determine a frequency. With the proper electronic hardness tester, not only can hardness be determined, but the depth of hardness can also be determined, voids, some grain structure.

Hardness testers can go into tens of thousands of dollars, but some of the portable ones are almost worth the risk to see if they actually work. This one on Ebay, I might pull the trigger...
https://www.ebay.com/itm/113704067925

Anyone experienced with a portable hardness tester?
 
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Kravt

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Dayton, OH
TDI
2005 Passat
I don't have access to anything other than standard testers like HRC and Vickers, though the Leeb hardness tester you linked seems like it would be super useful if accurate.
 

Kravt

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Jul 31, 2018
Location
Dayton, OH
TDI
2005 Passat
Took some pics of my new AMC camshaft to compare to the ones posted previously. Looks like there has been some change in manufacturing. Most obvious difference to me is the smaller lobe chamfers on the one I received. Overall looks decent to my eyes! Box says made in spain. I've got about 500 miles on it so far.





 

Kravt

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Location
Dayton, OH
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2005 Passat
[FONT=&quot]I also did a little analysis in a metallurgy lab. Was fairly pleased with the finish overall! That said, I do not really have previous knowledge in cams and their proper manufacturing tolerances.
I used a laser interferometer for most of the analysis but I did some optical micro as well. Below is one of the roughness measurements from the flat part of one of the camshaft lobes. This one came in at 9.636 microinches Ra. Most measurements ranged from 9-11 Ra.
[/FONT][FONT=&quot][/FONT][FONT=&quot]

Here is a similar measurement done on a nitrided lifter, you can see the scratch marks from some final polishing step. Pretty smooth at 3.68 microinches Ra.
[/FONT][FONT=&quot][/FONT]

[FONT=&quot] One thing that I found a little disconcerting about the camshaft is that I could see the transition from the flat parts of the lobes to the small-radius parts (the tip of the teardrop if you will). I had to look pretty close, but I could see the transition with my naked eye. Closer inspection with the interferometer showed there was some mismatch with the two surfaces. The chart in the bottom left is the cam profile of the transition between the flatter part of the lobe and the tip of the lobe. In my mind, it would be best to have less of a peak and more of a smooth transition around that 20mm mark, but I can't say if this is really that much of a defect. It's possible that most camshafts have this problem.
[/FONT][FONT=&quot]
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[FONT=&quot]Picture showing location of the transition in question:[/FONT]
[FONT=&quot]
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[FONT=&quot] This is the camshaft lobe surface under 2.5-5-10-20-50x. Frank06 I'm particularly interested in your thoughts on this. Does this look like the work of an improperly dressed grinding wheel? I don't have the experience to tell.
[/FONT][FONT=&quot][/FONT]
 

blazen71

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Oct 25, 2011
Location
Wiskullsin
TDI
All Gone
I'm guessing it from the change in direction in the axis of the machine and maybe a rotational speed change of the camshaft?
 

Kravt

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Joined
Jul 31, 2018
Location
Dayton, OH
TDI
2005 Passat
That's probably right. I'd say it could also be from incorrect grinding tool dimensions, assuming this is done by a CNC operation.
 

bruca003

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Nov 20, 2009
Location
toronto
TDI
2004 golf GLS TDI, 2005 passat wagon tdi.
My lifters and cam replaced at around 250K. Not sure what oil previous owner used or driving style. I now use motul engine oil and so far so good.
 
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