Timing adjustment methods - Page 11 - PeachParts Mercedes-Benz Forum

leathermang · #**151** 01-26-2011, 02:44 PM

So your 'cunning little plan' used WAY STANDARD OLD SCHOOL FACTORY PROVEN PROCEDURE.... LOL .... so much for your wild innovator image...
I have not seen what funola is selling... or heard about it until now...

Stretch · #**152** 01-26-2011, 02:50 PM

Quote:

Originally Posted by leathermang

So your 'cunning little plan' used WAY STANDARD OLD SCHOOL FACTORY PROVEN PROCEDURE.... LOL .... so much for your wild innovator image...
I have not seen what funola is selling... or heard about it until now...

I never claimed to be a wild inventor!

How on earth did you get that impression?

You need to do something sensible - particularly if you intend to do something that others think is daft. I mean I'd have a hard time explaining things to you (and others) if I couldn't communicate it by comparing it to something that would be understandable. That's almost an unwritten rule of research.

Funola's "invention" for want of a better term is here:-

Are you interested in an adjustable IP fuel pressure relief valve?

I think it is very smart.

Oh and by the way I think you could say that I was a "way standard old school factory proven" kind of person who is sometimes looking for a different way - that's all.

leathermang · #**153** 01-26-2011, 02:58 PM

Well, continuing after Whunter's post about the thermocouples compared to the glowplug's design was a little ( I am going ' there' no matter what facts are put in my way' )kind of impression... but many of the best inventions were considered crazy when first shown.. so no harm no foul in my book.. and there are other concepts which all play together to decrease the chances of success ... like the potential ' sensor' being hidden so well from the combustion chamber.. getting any readings through those little radial holes in precombustion chamber takes some forceful and sorta wild imagination..
but those two things are really needed by innovators.. so , once again, no harm no foul...

layback40 · #**154** 01-26-2011, 08:05 PM

Funola's 'invention' is a good idea !
There are probably many diesels being starved for fuel at high loads because the primary fuel pressure is low.
Any one wishing to play with the fuel system could benefit from it.
I have no justifiable idea what effect higher primary fuel supply pressures to the IP would have on injector timing. My intuitive thoughts are that low supply pressure could retard injection timing ever so slightly. It could also contribute to cavitation on the pumping elements.While these effects may be very small, they are still in the wrong direction.
Some where in a Bosch technical publication some place there is probably information on the effect of supply pressure on the IP operation. we all know what our diesels run like with a blocked secondary filter, low supply pressure is the same.

Army,
The Cat injector sensor is a shock sensor. I have a couple of machines with them. they are similar to the knock sensors that were used by Saab (apc system) & Porsche from the early 80's for their turbo control on gassers. The Saab ones looked like an extra electric temp sensor on the head. They detected the first sign of pinging & backed the boost off accordingly.
As far as detecting when injectors blow, my jeep (VM engine) has injectors like your 300D except #1 has an electronic sensor that detects when the injector opens. Its just a couple of wires coming out the top of the injector near the return line fittings. I guess its some sort of proximity sensor. it feeds the signal back to the brain box along with a signal from the crank position sensor & dynamically adjusts the injection timing for the rpm/load, its drive by wire, the brain box gets a signal from the throttle peddle, no mechanical link direct to the IP. I discovered that when I had the hood up & wanted to rev the motor from under the hood ~ cant do it!!
There is a ton of info ( you probably know what I mean) on ;
http://greatlakesxj.com/tech.html
You should be able to find some info on how it all works some where there.
I suspect with the sensor-ed #1 injector or a Cat style sensor & a crank position sensor (tach pic up), a small box of electronics could have you with a display of the injector timing over the rev & load range.

Stretch · #**155** 01-27-2011, 09:20 AM

Quote:

Originally Posted by layback40

Funola's 'invention' is a good idea !
There are probably many diesels being starved for fuel at high loads because the primary fuel pressure is low.
Any one wishing to play with the fuel system could benefit from it.
I have no justifiable idea what effect higher primary fuel supply pressures to the IP would have on injector timing. My intuitive thoughts are that low supply pressure could retard injection timing ever so slightly. It could also contribute to cavitation on the pumping elements.While these effects may be very small, they are still in the wrong direction.
Some where in a Bosch technical publication some place there is probably information on the effect of supply pressure on the IP operation. we all know what our diesels run like with a blocked secondary filter, low supply pressure is the same.

Army,
The Cat injector sensor is a shock sensor. I have a couple of machines with them. they are similar to the knock sensors that were used by Saab (apc system) & Porsche from the early 80's for their turbo control on gassers. The Saab ones looked like an extra electric temp sensor on the head. They detected the first sign of pinging & backed the boost off accordingly.
As far as detecting when injectors blow, my jeep (VM engine) has injectors like your 300D except #1 has an electronic sensor that detects when the injector opens. Its just a couple of wires coming out the top of the injector near the return line fittings. I guess its some sort of proximity sensor. it feeds the signal back to the brain box along with a signal from the crank position sensor & dynamically adjusts the injection timing for the rpm/load, its drive by wire, the brain box gets a signal from the throttle peddle, no mechanical link direct to the IP. I discovered that when I had the hood up & wanted to rev the motor from under the hood ~ cant do it!!
There is a ton of info ( you probably know what I mean) on ;
http://greatlakesxj.com/tech.html
You should be able to find some info on how it all works some where there.
I suspect with the sensor-ed #1 injector or a Cat style sensor & a crank position sensor (tach pic up), a small box of electronics could have you with a display of the injector timing over the rev & load range.

Great stuff - I'm reading and reading!

The shock sensor sounds dangerously close to my cunning plan #2 - which is to make a measurement or the engine's vibration and try and trace events back to crank shaft rotation. So now I've come clean. Cunning plans 3 and 4 are a bit pie in the sky so I'll not entertain you with them just yet!

All of these cunning plans are alternative ways of what I guess the using a glow plug method would be trying to achieve. I think it is important to compare methods in order to make realistic assessments: steady and slow and not at all mad inventor-ish - I hope you'll all agree!

leathermang · #**156** 01-27-2011, 10:30 AM

Quote:

Originally Posted by Army

Great stuff - I'm reading and reading!

The shock sensor sounds dangerously close to my cunning plan #2 - which is to make a measurement or the engine's vibration and try and trace events back to crank shaft rotation. So now I've come clean. Cunning plans 3 and 4 are a bit pie in the sky so I'll not entertain you with them just yet!

All of these cunning plans are alternative ways of what I guess the using a glow plug method would be trying to achieve. I think it is important to compare methods in order to make realistic assessments: steady and slow and not at all mad inventor-ish - I hope you'll all agree!

What " EXACTLY " is your ' glow plug method ' trying to achieve ? Have you written out your goal ?

AH, There's the rub.... matching whatever you find vibrating with the crank position.... well put.

Others " A bit pie in the sky "... as if the other plan is down to earth... just go ahead and share those with us so we can be thinking about them...LOL

So when did you get this feeling that you had too much time on your hands ? Does it happen every Winter.. Cabin Fever perhaps ? I can understand that...
LOL

Stretch · #**157** 01-27-2011, 11:49 AM

I spent a bit of time this morning trying to hunt down a thermometer so I could do the following a bit better - but all I got from the drongos behind the counters was "what do you need a thermometer for?"...

So I came home and just gave it a go.

If you attach a multimeter to a glow plug at ambient temperature (about 6 degrees C today) you get NO OUTPUT - well not one that I could measure anyway.

But if you heat the little bugger up with a blow torch (granted it would have been easier to just use the glow plug relay in the car to heat it but at the moment my engine is out - I'm in the middle of a rebuild - but I digress) you do get an output!

To be honest I am quite surprised.

It doesn't strike me as a particularly good reversible transducer but it does at this stage seem to me to be behaving like a transducer - we just have to see how good a transducer it is later on.

PS I didn't heat it for long as I didn't want to damage it - I know they make enough light to light up the prechamber when used for their real purpose but even so I was being super cautious. Besides they don't glow as a result of ignition.

leathermang=> time on my hands? Well that will be waiting for parts...

bmwpowere36m3 · #**158** 01-27-2011, 04:46 PM

Considering a glow plug has a resistive element, you could in fact use it as a thermosensor. Figure out its sensitivity (i.e. resistance changes with temperature) and you'll know the temp in the prechamber.

RichC · #**159** 01-27-2011, 07:23 PM

Quote:

Originally Posted by Army

I'd really like to see that report - it might cut down on some dead ends.

To be honest I'm not particularly interested in the magnitude of the output from the sensor I'm more interested in when it happens. We are talking timing here. I don't really care about an accurate temperature measurement I just need a big enough difference in magnitude above noisy mush so I can identify it (pick it out), and I hope it will be sudden enough - i.e. as much like a Dirac delta function as possible.

My cunning plan is to measure the event in another way - which I expect (and hope) will be way more reliable - and then see if I can compare this other method and an accurate measurement of the crankshaft rotation, with whatever output I can get from a temperature sensor.

But again - before I start on this - I'm just going to see if I can get a glow plug to measure some sort of sudden temperature change. If it can't do that then there is little point in adding any instrumentation to my engine (for this investigation anyway).

I really dont think you will get any sort of spike at each individual ignition point.
It may be possible but there is a lot of heat saturation going on with all that metal around.

But you can reliably get the highest temp at the glowplug at a set timing spot.

Slowly changing the injection timing changes the temp of the glowplug but there is a lag time, from what I remember its about 3 to 5 seconds.

The only thing I can see that would bust this method is if a glowplug would register a higher voltage at a lower temperature.

I know stranger things have happened, but I dont see this one happening.

RichC · #**160** 01-27-2011, 07:32 PM

Quote:

Originally Posted by layback40

Funola's 'invention' is a good idea !
There are probably many diesels being starved for fuel at high loads because the primary fuel pressure is low.
Any one wishing to play with the fuel system could benefit from it.
I have no justifiable idea what effect higher primary fuel supply pressures to the IP would have on injector timing. My intuitive thoughts are that low supply pressure could retard injection timing ever so slightly. It could also contribute to cavitation on the pumping elements.While these effects may be very small, they are still in the wrong direction.
Some where in a Bosch technical publication some place there is probably information on the effect of supply pressure on the IP operation. we all know what our diesels run like with a blocked secondary filter, low supply pressure is the same.

Fuel pressure is controlled on these pumps by a little bb and a spring in the banjo bold on the back of the IP pump on the return line.

If you want to increase the pressure, take the spring out and stretch it till you get the pressure you want. or use a different spring.

But I guess you will think this is C&%P information from an incompetent internet babbler also.

layback40 · #**161** 01-27-2011, 07:54 PM

Quote:

Originally Posted by RichC

Fuel pressure is controlled on these pumps by a little bb and a spring in the banjo bold on the back of the IP pump on the return line.

If you want to increase the pressure, take the spring out and stretch it till you get the pressure you want. or use a different spring.

But I guess you will think this is C&%P information from an incompetent internet babbler also.

I am sorry that the post of mine is a little to technically complicated for you to understand. I was simply commenting that such a device would be useful to some one wishing to vary the IP supply pressure with some degree of precision. Its definitely not for some redneck shade tree mechanic.

RichC · #**162** 01-27-2011, 08:14 PM

Quote:

Originally Posted by ForcedInduction

Where was that? All I see is that your method was completely disproved as pseudoscience.

Thats because you dont read the thread, you go to my user profile and click on all of my posts and try to troll me. Go Away !

Here is your answer...

Quote:

Originally Posted by Army

I spent a bit of time this morning trying to hunt down a thermometer so I could do the following a bit better - but all I got from the drongos behind the counters was "what do you need a thermometer for?"...

So I came home and just gave it a go.

If you attach a multimeter to a glow plug at ambient temperature (about 6 degrees C today) you get NO OUTPUT - well not one that I could measure anyway.

But if you heat the little bugger up with a blow torch (granted it would have been easier to just use the glow plug relay in the car to heat it but at the moment my engine is out - I'm in the middle of a rebuild - but I digress) you do get an output!

To be honest I am quite surprised.

It doesn't strike me as a particularly good reversible transducer but it does at this stage seem to me to be behaving like a transducer - we just have to see how good a transducer it is later on.

PS I didn't heat it for long as I didn't want to damage it - I know they make enough light to light up the prechamber when used for their real purpose but even so I was being super cautious. Besides they don't glow as a result of ignition.

leathermang=> time on my hands? Well that will be waiting for parts...

layback40 · #**163** 01-27-2011, 08:26 PM

Quote:

Originally Posted by Army

Great stuff - I'm reading and reading!

The shock sensor sounds dangerously close to my cunning plan #2 - which is to make a measurement or the engine's vibration and try and trace events back to crank shaft rotation. So now I've come clean. Cunning plans 3 and 4 are a bit pie in the sky so I'll not entertain you with them just yet!

All of these cunning plans are alternative ways of what I guess the using a glow plug method would be trying to achieve. I think it is important to compare methods in order to make realistic assessments: steady and slow and not at all mad inventor-ish - I hope you'll all agree!

You are welcome to practice a little science experimentation especially given that you appear to be wise enough to critically evaluate your findings.
I have no idea how sensitive the shock sensors are on say a Saab turbo from the mid 80's. It may be possible to attach one to the injector or the injector line. This would be far more sensitive than the GP idea. Probably not subject to hysteresis either. I am sure you have a better understanding of the properties of audio sensors like this than most.

What scale was your multimeter on when you got your reading?

At the end of the day though, we have no base line to compare a result to. If you work out some algorithm that relates your finding to the required IP timing for a drip test it could be used as a quick test. How repeatable will it be? Will it vary for a pre chamber full of coke that needs cleaning?
Lots for you to think about!

t walgamuth · #**164** 01-27-2011, 11:58 PM

Quote:

Originally Posted by leathermang

Hey guys, I do not want this thread closed due to you calling each other names...
Even if some of you might deserve that...
so get back to the things you want to talk about which are not the other person's personality attributes... Thanks, Greg

I agree. The ridicule and name calling is not needed here.

Stretch · #**165** 01-28-2011, 04:54 AM

Quote:

Originally Posted by layback40

You are welcome to practice a little science experimentation especially given that you appear to be wise enough to critically evaluate your findings.
I have no idea how sensitive the shock sensors are on say a Saab turbo from the mid 80's. It may be possible to attach one to the injector or the injector line. This would be far more sensitive than the GP idea. Probably not subject to hysteresis either. I am sure you have a better understanding of the properties of audio sensors like this than most.

What scale was your multimeter on when you got your reading?

At the end of the day though, we have no base line to compare a result to. If you work out some algorithm that relates your finding to the required IP timing for a drip test it could be used as a quick test. How repeatable will it be? Will it vary for a pre chamber full of coke that needs cleaning?
Lots for you to think about!

Hey layback40 - I added the information that I had found because I had one of those moments when, after reading lots of books, I actually saw something that you "know" is meant to happen happen.

It was a $%^%*$^&# me IT DOES ACTUALLY DO THIS moment - much like the time when the effect of electric insulation was "proven" to me:- at a wedding there was a beer cooler that was live. Some people complained of getting shocks - others didn't. The ones that didn't get shocks were wearing rubber soled shoes... take away the shoes and guess what happend...

...you "know" how things are meant to behave but it is nice to see it for real instead of just words in a book.

Anyway going back to the information I posted:-

This is a really basic simple observation - like I said I couldn't even get hold of a thermometer.

I plan to have a chat with a friend who works at a university to see if I can get access to some real instrumentation that will help me to compile some reliable measurements and calibrate the output of the glow plug.

If / when I get to that stage I'll start a new thread and stop bothering the good people who have pointed out that this information is off on a bit of a tangent from the original subject content of the thread. (I hope that a link to this new thread - if I write it - will be tolerated).