Introducing my timing light - injection timing- digital RIV method- bench test - Page 2 - PeachParts Mercedes-Benz Forum

Stretch · #16 03-07-2014, 08:09 AM

Quote:

Originally Posted by funola

Your test would reveal some useful, non existent data on our engines. I do not have a timing light with advance currently and cannot do the test. Maybe when I have a working unit, I can let you borrow it and you can do the test?

Ideally you need to hook the trigger sensor to the timing light and point that bugger at the graduated marks on the crank - as simple as that isn't it?

Quote:

Originally Posted by funola

...

Bad news:

I suffered a setback today. While installing the sensor into the IP timing plug, I damaged the wiring inside the sensor. It is not salvageable and is now junk since it is potted in epoxy. I have to come up with a better sensor design. What worked so well on the bench is no longer working on the bench. Damn, a lot of work went into that sensor! I have more parts on order which should arrive in a few weeks.

Shame that didn't work out.

funola · #17 03-07-2014, 10:41 AM

Quote:

Originally Posted by Stretch

Ideally you need to hook the trigger sensor to the timing light and point that bugger at the graduated marks on the crank - as simple as that isn't it?

Shame that didn't work out.

KarTek's test goes beyond that. Yeah, the damn wire within the sensor broke before I was able to turn power on. What a waste. I'll be back.

Stretch, on the last page of FSM 07.1- 010 operation injection pump with governor, can you translate the labels in the timing diagram? Some of them are in German I think.

http://mercedes.thatchermathias.com/w123CD2/Program/Engine/617/07_1-010.pdf

mach4 · #18 03-07-2014, 09:09 PM

If I'm understanding your project correctly, you're attempting to emulate a gas engine timing system with a diesel. You've been able to use a VR sensor to trigger a Xenon timing light on the desk. The plan is to use the IP as a trigger wheel and drive the timing light to read the timing on the front pulley. The tang on the IP you're attempting to read should read 15 degrees ADC if the timing is correct. Is that correct?

In thinking about the system I wonder if it is possible to use either a piezo pressure sensor or maybe even a piezo knock sensor as a trigger event for the timing light. The commercial systems use some kind of a clamp on the injector line that read the expansion of the injector line as pressure to trigger the timing function... at least that's the way I understand their operation. That would take a pretty sensitive sensor to read the tiny bit of movement of the line wall.

I'm wondering if it might be possible to create a more responsive and cheaper system that would use a high pressure piezo sensor or maybe even a knock sensor. What I'm thinking about is two sections of stock injector lines (red) connected at a block of aluminum, brass or steel to the #1 injector outlet of the IP. The green connectors in the below image are modified fittings from the IP. I've made a bunch of these fittings for use in a pop tester - metric injector fittings on one end and 1/4NPT on the other to make fabricating a connector block extremely simple. Reading the signal should be pretty easy, although I think it would be a rising edge rather than a falling edge you'd be looking for. If you can use a knock sensor they're dirt cheap - a pressure sensor, maybe not so much.

I may be completely off base with this idea, but who knows, maybe it would trigger some other options to accomplish the goal.

If you're using a VR sensor, you can use almost anything that would fit. RPM and speed sensors off the MB, cam position sensors, wheel speed sensors, and so forth.

Stretch · #19 03-08-2014, 02:10 AM

Quote:

Originally Posted by funola

KarTek's test goes beyond that. Yeah, the damn wire within the sensor broke before I was able to turn power on. What a waste. I'll be back.

Stretch, on the last page of FSM 07.1- 010 operation injection pump with governor, can you translate the labels in the timing diagram? Some of them are in German I think.

http://mercedes.thatchermathias.com/w123CD2/Program/Engine/617/07_1-010.pdf

OT means zero degrees TDC
v.OT means before TDC
n.OT means after TDC

Was that the bit you wanted?

Stretch · #20 03-08-2014, 02:13 AM

Quote:

Originally Posted by mach4

If I'm understanding your project correctly, you're attempting to emulate a gas engine timing system with a diesel. You've been able to use a VR sensor to trigger a Xenon timing light on the desk. The plan is to use the IP as a trigger wheel and drive the timing light to read the timing on the front pulley. The tang on the IP you're attempting to read should read 15 degrees ADC if the timing is correct. Is that correct?

In thinking about the system I wonder if it is possible to use either a piezo pressure sensor or maybe even a piezo knock sensor as a trigger event for the timing light. The commercial systems use some kind of a clamp on the injector line that read the expansion of the injector line as pressure to trigger the timing function... at least that's the way I understand their operation. That would take a pretty sensitive sensor to read the tiny bit of movement of the line wall.

I'm wondering if it might be possible to create a more responsive and cheaper system that would use a high pressure piezo sensor or maybe even a knock sensor. What I'm thinking about is two sections of stock injector lines (red) connected at a block of aluminum, brass or steel to the #1 injector outlet of the IP. The green connectors in the below image are modified fittings from the IP. I've made a bunch of these fittings for use in a pop tester - metric injector fittings on one end and 1/4NPT on the other to make fabricating a connector block extremely simple. Reading the signal should be pretty easy, although I think it would be a rising edge rather than a falling edge you'd be looking for. If you can use a knock sensor they're dirt cheap - a pressure sensor, maybe not so much.

I may be completely off base with this idea, but who knows, maybe it would trigger some other options to accomplish the goal.

If you're using a VR sensor, you can use almost anything that would fit. RPM and speed sensors off the MB, cam position sensors, wheel speed sensors, and so forth.

This approach has essentially been considered here =>

Injector line pulse frequency - help needed

The difference however is to not arse about putting in pressure transducers (you'd have to bleed) but to measure the elastic deformation of the injector line (clip on clip off)

Gregory · #21 03-08-2014, 09:26 AM

Quote:

Originally Posted by mach4

If I'm understanding your project correctly, you're attempting to emulate a gas engine timing system with a diesel. You've been able to use a VR sensor to trigger a Xenon timing light on the desk. The plan is to use the IP as a trigger wheel and drive the timing light to read the timing on the front pulley. The tang on the IP you're attempting to read should read 15 degrees ADC if the timing is correct. Is that correct?

In thinking about the system I wonder if it is possible to use either a piezo pressure sensor or maybe even a piezo knock sensor as a trigger event for the timing light. The commercial systems use some kind of a clamp on the injector line that read the expansion of the injector line as pressure to trigger the timing function... at least that's the way I understand their operation. That would take a pretty sensitive sensor to read the tiny bit of movement of the line wall.

I'm wondering if it might be possible to create a more responsive and cheaper system that would use a high pressure piezo sensor or maybe even a knock sensor. What I'm thinking about is two sections of stock injector lines (red) connected at a block of aluminum, brass or steel to the #1 injector outlet of the IP. The green connectors in the below image are modified fittings from the IP. I've made a bunch of these fittings for use in a pop tester - metric injector fittings on one end and 1/4NPT on the other to make fabricating a connector block extremely simple. Reading the signal should be pretty easy, although I think it would be a rising edge rather than a falling edge you'd be looking for. If you can use a knock sensor they're dirt cheap - a pressure sensor, maybe not so much.

I may be completely off base with this idea, but who knows, maybe it would trigger some other options to accomplish the goal.

If you're using a VR sensor, you can use almost anything that would fit. RPM and speed sensors off the MB, cam position sensors, wheel speed sensors, and so forth.

Instead of a two-part hard line, a small fitting for the piezo could be machined that either screws onto the injector, or the IP fitting; and the hard line screws onto the fitting. You would just leave it always in place.

funola · #22 03-08-2014, 09:29 AM

Quote:

Originally Posted by Stretch

OT means zero degrees TDC
v.OT means before TDC
n.OT means after TDC

Was that the bit you wanted?

Yes, thank you.

On the top chart, below the left most vertical scale line @ 24 deg v. OT, Is the = sign in "OT-I = RI = FB - P" meant to be used as a formula?

What does "FB" and "P" stand for? Is the "-" a dash?

Stretch · #23 03-08-2014, 01:36 PM

Quote:

Originally Posted by funola

Yes, thank you.

On the top chart, below the left most vertical scale line @ 24 deg v. OT, Is the = sign in "OT-I = RI = FB - P" meant to be used as a formula?

What does "FB" and "P" stand for? Is the "-" a dash?

I'll fire up (bloody) windows for you tomorrow and see if the original language FSM sheds some light on it all (pun intended)

funola · #24 03-09-2014, 05:15 PM

Quote:

Originally Posted by mach4

If I'm understanding your project correctly, you're attempting to emulate a gas engine timing system with a diesel. You've been able to use a VR sensor to trigger a Xenon timing light on the desk. The plan is to use the IP as a trigger wheel and drive the timing light to read the timing on the front pulley. The tang on the IP you're attempting to read should read 15 degrees ADC if the timing is correct. Is that correct?

In thinking about the system I wonder if it is possible to use either a piezo pressure sensor or maybe even a piezo knock sensor as a trigger event for the timing light. The commercial systems use some kind of a clamp on the injector line that read the expansion of the injector line as pressure to trigger the timing function... at least that's the way I understand their operation. That would take a pretty sensitive sensor to read the tiny bit of movement of the line wall.

I'm wondering if it might be possible to create a more responsive and cheaper system that would use a high pressure piezo sensor or maybe even a knock sensor. What I'm thinking about is two sections of stock injector lines (red) connected at a block of aluminum, brass or steel to the #1 injector outlet of the IP. The green connectors in the below image are modified fittings from the IP. I've made a bunch of these fittings for use in a pop tester - metric injector fittings on one end and 1/4NPT on the other to make fabricating a connector block extremely simple. Reading the signal should be pretty easy, although I think it would be a rising edge rather than a falling edge you'd be looking for. If you can use a knock sensor they're dirt cheap - a pressure sensor, maybe not so much.

I may be completely off base with this idea, but who knows, maybe it would trigger some other options to accomplish the goal.

If you're using a VR sensor, you can use almost anything that would fit. RPM and speed sensors off the MB, cam position sensors, wheel speed sensors, and so forth.

Sorry for the late reply. I've been busy. There are many ways to skin a cat and I see no reason why your method will not work. It may produce different results and you just have to characterize it with testing and measurements. I say go for it!

vstech · #25 03-09-2014, 05:23 PM

Bump

Stretch · #26 03-09-2014, 06:08 PM

Quote:

Originally Posted by funola

Yes, thank you.

On the top chart, below the left most vertical scale line @ 24 deg v. OT, Is the = sign in "OT-I = RI = FB - P" meant to be used as a formula?

What does "FB" and "P" stand for? Is the "-" a dash?

That formula bit if it is a formula doesn't exist on my copy of the German language FSM.

I think it should be ignored.