Mercedes V8 AMG cam and crank scopes

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whatthe
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Mercedes V8 AMG cam and crank scopes

Post by whatthe »

I feel like I've reached the end of the internet looking for some guidance for the cam and crank sensors for a 2003 SL55 AMG Mercedes with the M113K engine. If any place has some advice, I hope you guys have it. :D

I'm trying to help a friend set up aftermarket engine management on this M113K engine he has swapped into an older C class. In order to ensure the maker of the aftermarket engine management can build the base firmware to run the engine before we commit to the new ECU, I need an oscilloscope of the cam and crank sensors for this engine. Unfortunately, the engine is not buttoned up at this point (oil cooler lines not connected, wiring not completed etc., etc.) and I can't even crank the engine to be able to do this.

I believe the cam sensor is a 3 wire sensor part number A 0041536928, hall type pointing at camshaft gear/sprocket part number A1120500204 with 36 teeth. The crank sensor is only two wire, and looks like it only points at the flywheel (part # A1120320247) and I count 144 teeth.

It looks like these part numbers could share some common ground with other V8 mercedes, but I'm no Mercedes expert. I'm hoping that perhaps it matches other similar models around the era. If anyone on here has some advice, it would be greatly appreciated.

Thanks

andrewbishop66
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Re: Mercedes V8 AMG cam and crank scopes

Post by andrewbishop66 »

hi
Just a thought cant you do static timing using clock dial indicator and a graduated degree wheel on the crank

Thanks Andrew

whatthe
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Re: Mercedes V8 AMG cam and crank scopes

Post by whatthe »

Thanks for the reply Andrew.

I did ask if I could achieve what they want manually in some form, and they said they need a scope.

I don’t quite understand the ins/outs of setting up the firmware, but I think traditionally the cam and crank sensors are referenced from more defined trigger wheels with a limited number of teeth (say 12 teeth). From what I can see on assembly photos, service manual, etc. the crank sensor looks like it is only pointing at flexplate on the crank which has 144 teeth. If that is the case, I don’t know to define which one would be the index tooth since that tooth is likely not at TDC. Plus a scope I think would allow them to confirm if its rising/falling signal, etc..

I had found something for an E320, but no idea if it's correct for that car or even applicable. Could post that up, but not sure it would help.

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Re: Mercedes V8 AMG cam and crank scopes

Post by STC »

First, How many Cam Sensors on this Engine ? - I'm thinking it could have as many as 4.

Get the Oil Pipes etc, buttoned up so it is safe to crank for just 5 seconds, fit the starter and crank it direct from the starter terminal 50, tied up on the floor if need be, with the spark plugs removed to reduce vibration.

The 3 pin Cam sensors will need a 5v Supply which you can get from a bench power supply or a Phone Charger / USB. The 2 Pin Crank sensor should be Inductive - Crank it and scope it to confirm.

whatthe
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Re: Mercedes V8 AMG cam and crank scopes

Post by whatthe »

In this case, from the ME SFI wiring schematics in the service manual it only uses the single cam sensor and single crank sensor back to the ECU.

I suspect the results of the scope would be the same for any of the supercharged or non-supercharged 4.3, 5.0, or 5.4/5.5L M113 derivative V8s of the era (2000-2007ish? but some like G55 used this engine even much later) - like CLK 430, CLK 500, G55 AMG, ML430, ML500, E500, E55 AMG, S430, etc.. in case that helps anyone track down a scope they've perhaps done in the past. Part numbers for cam sprockets, cam/crank sensors, flexplate, etc. all appear the same anyway.

That's a good point about USB charger as a voltage supply. I may have to go that way, but I'm at least a month or so away from having some other parts here so that I can button it up which really delays starting on the ECU side. I have to get the aftermarket coolers so I can stuff them where they will fit on the old C chassis, and then build custom lines to them. Thinking that it is also probably a good idea to unload supercharger and activate recycle valve while cranking as well.

I've got the following info on the sensors from translating a french MB service doc that I found for the sensors, but can't seem to find an actual reference to an actual scope + diagnosis in the manual that I have.

-----


L5 Crankshaft Position Transmitter
C Slot (2 missing teeth)
D Incremental pinion teeth (magnetic conductor)
The position of the crankshaft and the engine speed are entered without contact. The distance between the transmitter
The crankshaft position (L5) and the teeth (d) of the clutch disc (incremental wheel) is given by
Mounting position (approx. 0.8 mm).
When the crankshaft rotates, the teeth of the drive disk produce an AC voltage (induced)
In the crankshaft position transmitter

The front edge of a tooth (a) produces a positive voltage pulse and
The back edge of a tooth (b) a negative voltage pulse. The
Distance between the positive voltage peak and the negative voltage peak
Corresponds to the length of a tooth.
The slot (c) of the 2 missing teeth causes no tension
Produced in the crankshaft position transmitter. This niche
Serves to detect the TDC on cylinders 1 and 6.

A Front edge of a tooth
B Back edge of tooth
C Slot (2 missing teeth)
H Crankshaft position transmitter signal
L Shielded signal line
S Inductive coil
V Tension
-----

B6 / 1 Camshaft Hall Sensor
A Segment on camshaft sprocket
B PMH of ignition to cylinder 1
C Schematic representation of the Hall transmitter
D Rectangular Signal Transmitter Hall
The signal line of the cam shaft transmitter has a signal of
Voltage of approx. 12 V ("high"). When the segment of the
Cams passes in front of the cam shaft transmitter, the signal
Changes abruptly to 0 V ("low").
This signal "0 V" is used to recognize the ignition PMH at cylinder 1 (b)

In the absence of the signal from the cam shaft transmitter, the calculator ME determines the ignition PMH of the cylinder 1 (N3 / 10) arbitrarily.
The motor starts approx. 1 s later and the content of polluting gases is not optimal.

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Re: Mercedes V8 AMG cam and crank scopes

Post by STC »

You have found some really good information there. I am guessing that the ECU designer has rejected it and wants a scope trace of Cam / Crank.

Not the best idea but you could risk cranking it for 2 turns on the crank.

whatthe
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Re: Mercedes V8 AMG cam and crank scopes

Post by whatthe »

Well to be fair, I only found that info the other day. If I search for 'crank' or 'cam' sensor using the service manual search feature, nothing comes up. But, apparently by fumbling through various links, eventually something good comes up. :lol:

Still will need a scope log for last bits of info. I"m sure oil pressure wouldn't build up for potentially several seconds (anyone who has waited for oil to come out of a turbo oil feed line before attaching new turbo, might know this joy), but will probably wait until I have couple more things buttoned up anyway.

Thanks for the suggestions

Liteace
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Re: Mercedes V8 AMG cam and crank scopes

Post by Liteace »

I have access to a E55 AMG, the people the own the vehicle are more often that not away sunning it on a beach somewhere in the world, I'll find out if / when they're here and grab a cam / crank trace for you

whatthe
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Re: Mercedes V8 AMG cam and crank scopes

Post by whatthe »

If you were able to, that would definitely be amazing. I would feel like I'd owe you some beer or something at least for that. :D

whatthe
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Re: Mercedes V8 AMG cam and crank scopes

Post by whatthe »

Just as an update, I believe I found what I need from a link within a link within a link within a link (you get the point... not sure I could ever find it again) in the service manual for C43 AMG.

The cam/crank signals are overlayed against degrees, firing order, time etc..

Given how the link was buried, a confirmation would still be nice, but less of a panic.

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