loudandheard

So we were talking about a potential fatal flaw in the design of the cams in the 2002 C32's and I would imagine that it would include other 32 models that were made in 2002 and before. Apparently the 2002 cams are a multi-piece part pressed together at the factory, not a 100% sure if this is true or not and what years it affects, but it will make more sense in a bit. The idea is that the cams are driven from the front and over time, because it is not a one-piece design, the end part of the cam may loosen, again not confirmed.

The thing that makes this seem more probable is because the MB EPC lists the original cam part # as A1120505391 and A1120504201. There is also a note next to both part numbers "Replaced by: A1120505301 and A1120505401. OLD PART MUST NO LONGER BE INSTALLED". So why would MB change the cams if there was not a problem with the original and why are the parts not interchangeable?

A few people have blown their engines recently and it makes me wonder if the cams could be contributing to this and there are a few others that have had similar problems.

Here are a few threads that relate to possible cam problems and the relation to people that have blown their engines having 2002 C32's.

This is the thread that got me thinking about this problem:
https://mbworld.org/forums/c32-amg-c...-bad-idea.html

This is the thread that I got most of my info about the potential problem with our cams:
https://mbworld.org/forums/c32-amg-c...mpression.html

Temjinx2's thread about his blown engine experience relating to tune, but you will notice that he has a 2002 C32:
https://mbworld.org/forums/c32-amg-c...xperience.html

Chamm's C32 was also a 2002, maybe a coincidence:
https://mbworld.org/forums/c32-amg-c...mine-dead.html

Not sure if this was a 2002, but the problem seems very similar:
https://mbworld.org/forums/c32-amg-c...roke-down.html

Here's another 2002 C32 with a blown motor:
https://mbworld.org/forums/c32-amg-c...ats-worth.html

2002 c32 with blown head gaskets, maybe not related to cams:
https://mbworld.org/forums/c32-amg-c...hink-help.html

Frankw's experience with cam issues, also a 2002:
https://mbworld.org/forums/c32-amg-c...ease-help.html

https://mbworld.org/forums/c32-amg-c...arranty-2.html

So I may be reaching with a few of these problems that fellow members have had, but a lot of them seem similar and they were mostly 2002 cars. Some of the 2002 cars were modded with 185mm pulleys and maybe that's the reason that the failure was more catastrophic. I know that there were probably more C32's made in 2002 than any other year and they have been around a lot longer and that could be the reason why engines have been blowing, but I haven't seen a lot of 2003+ blown engines. I have not taken any srt-6 engines in to consideration, so I do not know how many of their engines have blown. I just think that we will be seeing a lot more problems with 2002 C32 because of the cams that were not updated in 2002.

Are my fears unwarranted, should 2002 C32's update their cams or just be more careful with their vehicles? I maybe over reacting, but it's better to be safe than sorry. All I know is that cams cost a bit more than 1k and that does not include installation.

I would rather have aftermarket cams, but I do not know of any one that produces them for the m112k at the moment. I think PTE maybe able to make cams for us, but who knows.

TemjinX2

i thought only the slr cams made power? Not sure if its multi piece or not. How can you tell? My new motor is a 2003 though.

FrankW

the new cam for the driverside i got was of the new part number. they are still pressed together.

schrick had a cam for the C32, but they're discontinued as the demands for them are not high.

loudandheard

Per wikipedia (not always accurate):
"All M112 engines have aluminum engine blocks with a 90° vee angle with silicon/aluminum lined cylinders. The aluminum SOHC cylinder heads have 3 valves per cylinder. All use SFI fuel injection with two spark plugs per cylinder. All have forged steel connecting rods, a one-piece cast camshaft, iron-coated aluminum pistons and a magnesium intake manifold. To deal with the vibration problems of a 90 degree V6, a balancer shaft was installed in the engine block between the cylinder banks. This essentially eliminated first and second order vibration problems. A dual-length Variable Length Intake Manifold is fitted to optimize engine flexibility."

http://en.wikipedia.org/wiki/Mercedes-Benz_M112_engine

I was thinking that the new part number would be a forged cam Frank, you think it was a pressed multi-piece cam?

loudandheard

I think it's only on 2002 engines, but I do not even know if the recent problems could be do to cams. If there was only a way that you could check out your cams to see if they contributed to the problem. I'm thinking you should be safe, as long as your car is a 2003 and has the new cam part numbers.

Frank, did installing a new cam in your vehicle solve your problem after all.

FrankW

all M112 does have 1 piece cam except M112K.

the new cam did solve everything. you can check my main thread. there is a picture of the bad cam i replaced on page 57.

loungn14

we replaced the cams in a 02 c32 (with the new part number) as well and it corrected a ton of issues the driver was having.

Jerry had the upgraded cams in his C32, but $ to power wasn't worth it.

loudandheard

What kind of problems was he having and what did it solve? I really do not care to replace my cams, but if it will keep me from having problems or even blowing my engine, then it's money will spent. I just wish we had a few different options rather than stock.

I think that the cams come out to be a bit over $1100 stock, does any one know of cheaper prices or alternatives.

I do not currently have any problems with my car, but it just doesn't feel as strong as it use to and I worry that if I do any sort of mods it could cause a worse problem. I wonder if cams would cure the sluggishness and if it's even worth doing. What would every one say?

doom239

http://www.eurocharged.com/index.php...mart&Itemid=61

Kleeman Camshafts

loudandheard

The question now is, how much? I'm sure they're probably going to want over 2k. If it can be had in the neighborhood of 1k, I may be able to go for it in the near future.

Lenin

Well... Just call and ask.

c32kompressor

i have been hearing a loud ticking noise from the block heads for a while now and it is starting to get a bit louder. the car had 118k miles and after reading this im a bit worried. if anyone else has had this problem, im thinking the cams are falling apart! or maybe its the lifters?? or possibly a combo of both! it is really loud and with the hood up the ticking is really loud, but when the hoods closed its quiet but still notice able form a 20-30ft distance. my car IS a 2002 and does have high milage.

FrankW

probably just valve sticking if you don't have a misfire idle issue.

loudandheard

Mine is pretty loud too, but so far I haven't had any check engine lights and the car seems to idle and accelerate smoothly.

JUAN CASAUS

Mine does the same but no issues except the noise

I give up

I own a 2001 C32 with 135 000km on the clock and in November 2010 I did the 185mm pulley, headers, full exhaust, ECU and airfilter conversion and developed a misfire the next day. We changed plugs, leads, coilpacks, etc. We even had the heads reconditioned and the cam lobes re-alinged and welded into position. Nothing helped. After lots of time and money it turned out that piston number 3 had shattered and caused catastrophic cylinder damage. I sourced a secondhand 2002 engine and it was re-installed along with all the original mods. 3 months later the misfire was back between idle and 3000RPM, along with a smoking tailpipe. On opening the engine we found the plugs on cylinder number 4 covered in oil. We are going through the entire process again of checking valves, cams, etc, but I have a feeling that I have managed to blow the rings/piston again. There are no more second hand engines to be had anymore so I am stuck with reboring the block out to a 3.5L and fitting Wiseco pistons/rings, etc. This is going to cost another fortune and another 2 months of having no car, but I cannot bring myself to selling it. The worst part is that I have no guarantee on my second rebuild as we still can't find the problem. Help.

newbenz2

Hi everyone,
I think I might have this problem. i did a search and only found 2 places that make aftermarket cams for the c32. Kleemann and Schick. Where are the best prices for these? I only saw the ones on eurocharged website. Also how much are stock replacement cams?
kevin

Lenin

Last time I looked, neither Kleemann nor Schick were making them any more.

newbenz2

Do you know anyone who has a cam card for the specs? Also where might I be able to find a used set? I can have them welded and ground, I have a pretty good cam guy.
Kevin

loudandheard

Here are the replacement part numbers: A1120505301 and A1120505401
Parts.com has them for $626.75 and $609.50.

Capn

Sorry to bump an old thread but are folks with 2002 M112K and experiencing camshaft failures stock or modded? daily driver or track car?

My 02' SLK32 has 115K miles and it drives like a dream but I have no idea how to check to see if my cams are multi-piece or single because it had 4 previous owners and no service records.

Also does anyone know if there is a factory service bulletin/recall on this issue?

jvakos

FrankW - digging up old thread here. i have this loud ticking noise coming from left engine towards the rear and after searching the boards here I am thinking its valve related as you mention

if this is a valve sticking causing that per your post, does that require replacing the sticking (or damaged?) valve or is that sticking something that can be cleaned out perhaps the oil/gunk thats built up?

i have 112,000 miles on the original engine that i've owned 8 years now. have some mods but its mostly a daily driver and until just now i've experienced this sound.

i did just get an oil change 1 month ago which is when the noise started, so might go back to that shop and see what they have to say

thx