So if you were measuring the distance in time between a pulse made per revolution on the crankshaft turning at 600rpm you'd have 10Hz => 0.1 seconds between each pulse.

Pulses made at the camshaft / IP delivery line happen at half the speed - so the time between each pulse would be 0.2 seconds which means a frequency of 5Hz

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Lot's of good info! These conversions can get confusing with mistakes easily made. Shouldn't half speed be 0.05 secs between ea pulse thus 20 hz?

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

It is confusing - and I'm having a day and a half today; I could have sworn I bought some subframe mounts - I can't find the buggers any where...

...I digress as usual...

...if something is running at half the speed it will take twice as long "to get there"

So with the pulse happening every 0.1 seconds - running at half the speed would mean a pulse "arriving" every 0.2 seconds.

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

You're right. I gotta wakeup myself. rev per minute, cycles per sec, frequency, period, 1/2 speed of one , twice the speed of another can get me mixed up real quick lol.

OK, so the IP runs at 1/2 speed of the crank.

Here's a gif of a 4 stroke engine.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

The injection duration is only 30 degrees or so, occuring every 720, or 1/12 rev, occurring every 2.

600 RPM = .1 sec / rev.
100 ms / 12 -> injection duration ~8ms, occuring every 200 ms.

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CC: NSA

All things are burning, know this and be released.

82 Benz 240 D, Kuan Yin
12 Ford Escape 4wd

You're four times

It's hard to

more likely to

concentrate on

have an accident

two things

when you're on

at the same time.

a cell phone.

www.kiva.org It's not like there's anything wrong with feeling good, is there?

I have no idea there.
The Element Plunger always has the same lenth of stroke on inline Fuel Injection Pumps.
It is how the Helix on the Plunger is Cut that determins what is called the "Effective Stroke" of the Plunger. Effective meaning the amount of the Stroke that is actually delivering Fuel.

As an example when the Element Plunger is rotated to the Shutoff Position the Plunger is still moving up and down as the Engine Rotates but the Plunger is rotated so the Helilx/Cut in the Plunger always exposes the Fuel Feed/Inlet Hole in the Barrel of the Element.
So in this case the Plungers effective stroke is zero and the Fuel that went into the the Element and is actually displace by the Plunger going up is expelled out of what I called the Fuel fill Hole (this violent expelling of Fuel is one of the reasons a Fuel Pressure Gauge Needle jumps).

The Time that the Helix covers the Fuel Feed Hole determins the length of Injection time (and amount of Fuel Injected) as does the rpm the Fuel Injection Pump is turning.

Simply put the amount of Injection Time is going to vary with the amount of Fuel Injected and the rpms of the Fuel Injection pump.
Someone who knows a lot about Physics and Math with the right measurements could calculate the speed of the Plunger moving up during Engine Rotation.

But, it is way easier to do the Measuremt as you are doing it now.

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84 300D, 82 Volvo 244Gl Diesel

When I was in Trade School I was told there is an actual Hydraulic Pressure wave/s going on inside of the Fuel Injection Lines so He is not just picking up Sound.

(Think of the more well know "Water Hammer" Pressure wave that happens when something explodes next to a Ships Hull.)

Although Sound can also cause a pressure way I doubt if it can do so with much magnitude in this situation.

Also not commented on is that the Fuel Injection Hard Line is going to expand during pressure and contract back to size during periods of no pressure.

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84 300D, 82 Volvo 244Gl Diesel

I'm not sure if I go along with that - 30 degrees could be right but that sounds a bit long even at high engine (crankshaft) speeds.

(The injectors on an OM61X are just valves that release - this will happen within a set time - every time. The timing device is used to make these valves release earlier to compensate for higher crankshaft speeds but to also allow enough time for burning)

One thing that we can be sure about is the difference in degrees between the point of delivery and the point of release. That information I've documented here =>

Dynamic diesel timing (renamed thread)

For a (non turbo) OM617 the begin of delivery happens at 24 degrees before TDC and the point of release is at 19 degrees before TDC. So 5 degrees of crank rotation is all that is used to build up the pressure behind the injector before it goes sput...

...I've calculated the time taken for the crank to turn one degree at 600 rpm (some one please check my maths I'm not having a good day today!)



So I reckon at 600rpm it takes 1.4ms to build up pressure and have it released - ideally this should be a feature that can be seen in this pulse.

If you go backwards with this 40ms event that has been noted in the first picture at 600 rpm that equates to a crank rotation of 143 degrees


Now what do you think happens every 144 degrees on a 5 cylinder OM617????????




@ funola = are you sure the time base measurement is correct? One square = 10ms?

Attached Thumbnails

 

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

{hint 720 /5}

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

If I try to apply this on the VE type pumps then this entire fuel increase deal is handled by the "spill sleeve"

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

Time base was set at 10 ms/ division. However, I was not able to get a steady trigger on the noisy signal (the waveform was moving horizontally).

I will try to look at it again dual trace triggering on the crankshaft rpm signal. Hopefully that will be a more periodic signal that the scope will trigger on.

BillGrissom, Good point about the vibration clamps on the lines conducting vibrations from an adjacent line. The piezo guitar pickup is just clamped onto the line by a not very strong spring. Instead of measuring sound, what I really would like to be able to measure is the expansion/ contraction of the line with the piezo sensor. To do that I think I'd have to make a better mount for the sensor. I don't know if it will work or be sensitive enough. If it can discern the expansion/ contraction of the line, then adjacent line noise is no longer an issue.

__________________
85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Post up a picture of the sensor set up please.

In case it isn't clear I think the second blip in your picture is the second point of release - firing order OM617 = 12453

If you put the sensor on injector line #5 I reckon there's a chance you get a smaller second spike as the next to fire will be cylinder #3 - a bit further away from one is to two...

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Actually, you might get a medium spike --> large spike --> small spike due to #4 going off just beforehand.

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"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."

It is somewhat similar as the Plunger on the VE also has the same stroke all of the time and the Metering Sleeve sliding on the Plunger adjusts the effective Stroke of the Plunger.

There is a lot of info on the Internet for the VE Pumps at VW and TDI sites.

However the VE Plunger rotates.
Some Fuel Injection Pumps used by Caterpillar also use the Sleeve Metering.

__________________
84 300D, 82 Volvo 244Gl Diesel

[IMG][/IMG]

__________________
85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked