"Timing Advance Mechanism" on IP: What is this? - PeachParts Mercedes-Benz Forum

Couper · #1 01-25-2012, 07:49 PM

Hi Guys,

I have been trying to get my 1984 300TD running for weeks. Please help me recover from another painful self inflected wound......

I just broke what I think is called the "Timing Advance Mechanism" on the Injection Pump on my '84 300TD. It's the square box that is attached to side of the IP with an attached wire that goes to the firewall. As I just found out, it is found only on the OM617 in 1984 and 1985.

Please help me with the following:

1. What does it do?

2. Can I get one at the junk yard without having to remove the IP?

3. Will an 1983 IP without a Timing Advance Mechanism work with on my 1984 w123? What needs to be done?

Thanks in advance. Any information is greatly appreciated as I'm really beating myself up for ripping out the wire from the box("TAM").

layback40 · #2 01-25-2012, 08:15 PM

Pic please

Couper · #3 01-25-2012, 08:22 PM

I unable to get the pictures from my camera to computer...just one of those days.

Here is a link to some pictures of IP and description of "Timing Advance Mechanism":

MERCEDES=300SD&300D DIESEL INJECTION PUMP 1984&85 for sale

Sorry to make you click away.

Diesel911 · #4 01-25-2012, 08:22 PM

The Fuel Injection Pump Timer is under where the Vacuum Pump is.

I believe what you are speaking of is the Fuel Rack Position Sensor.

I also believe I read that the Sensor is what actuates the EGR; someone else will have to verify that.

mach4 · #5 01-25-2012, 08:31 PM

Quote:

Originally Posted by Diesel911

The Fuel Injection Pump Timer is under where the Vacuum Pump is.

I believe what you are speaking of is the Fuel Rack Position Sensor.

I also believe I read that the Sensor is what actuates the EGR; someone else will have to verify that.

Yup, that's what I would say it is based on his description...

mach4 · #6 01-25-2012, 08:34 PM

And it is definitely part of the EGR system. This is the wiring diagram for the EGR Controller (80 in the below diagram is the connector to the controller.)

47dodge · #7 01-25-2012, 08:35 PM

quess it is time to block off egr and be happy.

Couper · #8 01-25-2012, 09:14 PM

Yes...I'm happy now. Which is totally opposite to what I was feeling a few minutes ago.

You guys are amazing!! Really appreciate how quickly and informative your replies are.

So I could post my question, I spoke to a Mercedes Dealer Parts specialist with 25 years of experience. He couldn't identify the part after checking his computer and several Bosch manuals.

Please comment on what I plan to do. Perhaps help my avoid further damage and dozens of hours of frustration.

Fuel rack position sensor is not necessary so the 1983 IP without it is swapable with 1984 IP with it.

I have a '83 300TD with what I think is a rebuild IP. I'm going to swap the '84 IP with broken Fuel Rack Position sensor with the rebuild '83 IP. Any concerns or advise?

compu_85 · #9 01-25-2012, 09:40 PM

The only function the rack position sensor has is to give an input to the EGR computer. If you are not concerned about having the EGR working leave it broken.

Stretch · #10 01-26-2012, 02:58 AM

Quote:

Originally Posted by Couper

...

I spoke to a Mercedes Dealer Parts specialist with 25 years of experience. He couldn't identify the part after checking his computer and several Bosch manuals.

...

Well you know where to come next time - 25 year experience of what I wonder?

Couper · #11 01-26-2012, 01:20 PM

@Army: He is the "go-to" parts guy at Beverly Hills MB that has work at MB dealer parts department for 25 years. Really nice guy, but I agree, this community is awesome!

I'm committed to the Mercedes diesels for the foreseeable future. Only hope I will be able to contribute more sooner than later.

I still can't believe how quickly and easily mach4 was able to post the diagrams. mach4, where did you get those?

Thanks again guys!

Stretch · #12 01-26-2012, 01:34 PM

I think you'll find out that lots of experts know very little about diesels.

You'll be surprised how quickly you'll be contributing - there's always something new to learn.

Good luck and welcome to the forum.

mobetta · #13 01-26-2012, 02:41 PM

Any parts guy who works at a dealership iz going to have better knowledge of the most recent models, not our cars. Even one who has been there since the beginning of the 123 cars

mach4 · #14 01-26-2012, 03:05 PM

Quote:

Originally Posted by Couper

I still can't believe how quickly and easily mach4 was able to post the diagrams. mach4, where did you get those?

I don't recall exactly, as I've been doing so much research on my project recently, the sources are all running together - in fact it was only 2 weeks ago that I was trying to figure out what was going on with the EGR system and asking where the controller was located - http://www.peachparts.com/shopforum/2863984-post155.html

Your question came at a good time since the information was fresh and readily available from that research.

Couper · #15 01-26-2012, 03:39 PM

@Army: He is the "go-to" parts guy at Beverly Hills MB that has work at MB dealer parts department for 25 years. Really nice guy, but I agree, this community is awesome!

I'm committed to the Mercedes diesels for the foreseeable future. Only hope I will be able to contribute more sooner than later.

I still can't believe how quickly and easily mach4 was able to post the diagrams. mach4, where did you get those?

Thanks again guys!