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  #31  
Old 04-01-2013, 09:31 PM
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You may have to get into tech literature. The rate of burn of various fuels is differant. The diesel presents a longer lasting burn period than a gas engine I believe. Strange but cylinder four seems to be the only primary culprit now. Probably will have to be dealt with.

I always suggested and thought that the engine be at operating temperatures for the milli volt readings. I also forgot it was operating on waste motor oil instead of waste vegatable oil as well.

Just as a curiosity do you read the acidic level of used motor oil before using it? If it is acidic buffering it would be easy and cheap. I thought sulfuric acid could be encountered in used motor oil. At what concentration is unknown to me if true. Cheap ph strips could enable a simple test.

Your possibilities seem less complex now. Make sure to correct the initial pump timing or verify it is late. If so after correction if it is retarded just bringing the number four cylinders milli volt readings into line . The injection pump is almost certain to be retarded as with that much milli volt differance you should hear that cylinder knocking on diesel fuel with the correct timing.

That is providing the glow plugs are putting out equal outputs for the heat they are experiencing. The answer for the number three cylinders carbon lacking issue now seems lost. Your new voltages are more like what to expect with the timing pretty close in general though. But there are varients like idle speed etc that can tweek them as well. Enough people have not used the milli volt system on the 616 and 617 diesels for us to get any form of really well established baselines yet.










At what concentration


Last edited by barry12345; 04-01-2013 at 09:51 PM.
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  #32  
Old 04-01-2013, 10:51 PM
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Quote:
Originally Posted by barry12345 View Post
You may have to get into tech literature. The rate of burn of various fuels is differant. The diesel presents a longer lasting burn period than a gas engine I believe. Strange but cylinder four seems to be the only primary culprit now. Probably will have to be dealt with.

I always suggested and thought that the engine be at operating temperatures for the milli volt readings. I also forgot it was operating on waste motor oil instead of waste vegatable oil as well.

Just as a curiosity do you read the acidic level of used motor oil before using it? If it is acidic buffering it would be easy and cheap. I thought sulfuric acid could be encountered in used motor oil. At what concentration is unknown to me if true. Cheap ph strips could enable a simple test.

Your possibilities seem less complex now. Make sure to correct the initial pump timing or verify it is late. If so after correction if it is retarded just bringing the number four cylinders milli volt readings into line . The injection pump is almost certain to be retarded as with that much milli volt differance you should hear that cylinder knocking on diesel fuel with the correct timing.

That is providing the glow plugs are putting out equal outputs for the heat they are experiencing. The answer for the number three cylinders carbon lacking issue now seems lost. Your new voltages are more like what to expect with the timing pretty close in general though. But there are varients like idle speed etc that can tweek them as well. Enough people have not used the milli volt system on the 616 and 617 diesels for us to get any form of really well established baselines yet.










At what concentration

WMO is not being used for these tests. I have not put any WMO in the tank in over a month. All tests recorded are on straight D2 from the pump. I have filled up at least 6 times since running any other fuel in the car.

The WMO that was run in the car was not tested for Ph. Acidity can be a concern in some situations. The WMO was settled with at least 15% gasoline and then filtered to 1 micron before entering the fuel tank. I have run about 70 gallons through the engine since I bought the car 15 months ago; at varying concentrations.

The symptoms of white smoke and rich fuel smell have existed since I bought the car but recently became more noticeable without obvious cause.
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1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
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  #33  
Old 04-01-2013, 11:02 PM
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Sorry I also knew you were on regular diesel currently.I was just trying to correct the waste motor oil versus wvo issue.

I still think now that if you have never checked the injection pump timing since aquiring the car. Previous owner or owners may have retarded the timing to cover up the number four cylinder issue would not suprise me. If so should be an easy fix. Hopefully that will be all of it.

.I also do not think either that putting only seventy gallons of used motor oil through has particualrily had any negative effects. Other than perhaps some carbon buildup.
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  #34  
Old 04-01-2013, 11:08 PM
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Originally Posted by barry12345 View Post
Sorry I also knew you were on regular diesel currently.I was just trying to correct the waste motor oil versus wvo issue.

I still think now that if you have never checked the injection pump timing since aquiring the car. Previous owner or owners may have retarded the timing to cover up the number four cylinder issue would not suprise me. If so should be an easy fix. Hopefully that will be all of it.

.I also do not think either that putting only seventy gallons of used motor oil through has particualrily had any negative effects. Other than perhaps some carbon buildup.

I agree. My next step will be checking the timing. I prefer a few degrees advanced timing in my Diesels. I tend to see better performance and a more complete burn of the fuel. Maybe it is compensating for years of wear and timing stretch but I do notice an improvement within a sweet spot. Obviously, over-advanced timing does not benefit but a few degrees seems to help.
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1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge
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  #35  
Old 04-23-2013, 12:17 PM
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The brake job took priority over checking the timing this weekend but I did notice a mark on the IP and where it mounts to the engine. I noticed this after washing the engine bay. The mark is about 1mm off from the IP and engine relationship. That leads me to believe someone at some point did something with the IP unless those marks are from the factory. Anyone here have a clue as to what may have happened in the past?

Edit: I will need to look again and take a picture but I believe the IP was canted toward the engine judging from the marks.
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1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge
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  #36  
Old 04-23-2013, 01:04 PM
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Probably advanced a little at some point to compensate for chain wear. Not probably relavent overall for current problem.

That is the mark and small timing advancement from the mark.
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  #37  
Old 09-24-2013, 11:21 AM
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I was poking around in my engine bay the other day and noticed that I was completely mistaken about the witness mark being advanced. The IP is actually canted away from the engine; making the timing retarded!!!
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1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge
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  #38  
Old 09-24-2013, 01:36 PM
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Back on track hopefully. I did not go back over your posts but have the valve settings ever been checked since you got the car? This just came to mind because of some milli volt variences I thought I noticed in your several test results. Sometimes they seemed good and other times bad. Changing valve stem lengths with thermal condition came to mind.

I am also getting more interested in making sure fuel pressure supply is good in the injection pump before going too far along. I think the fuel pressure is not the problem but can be contributing to any varying of the mili volts may be an outside highly unlikely remote possibility.

Closing off the relief valve line may change the milli volt readings if there is currently overflow from the relief valve. If no flow exists the fuel pressure may be too low anyways for good general performance.

For the time it takes not being certain of anything sometimes I do a tune up before really getting into the predominate issue. It is just my method of trying to reduce the everyday experience value I lack as a working mechanic a little. They develop a form on intuition instead that is priceless over the years.
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  #39  
Old 09-24-2013, 05:40 PM
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Originally Posted by barry12345 View Post
Back on track hopefully. I did not go back over your posts but have the valve settings ever been checked since you got the car? This just came to mind because of some milli volt variences I thought I noticed in your several test results. Sometimes they seemed good and other times bad. Changing valve stem lengths with thermal condition came to mind.

I am also getting more interested in making sure fuel pressure supply is good in the injection pump before going too far along. I think the fuel pressure is not the problem but can be contributing to any varying of the mili volts may be an outside highly unlikely remote possibility.

Closing off the relief valve line may change the milli volt readings if there is currently overflow from the relief valve. If no flow exists the fuel pressure may be too low anyways for good general performance.

For the time it takes not being certain of anything sometimes I do a tune up before really getting into the predominate issue. It is just my method of trying to reduce the everyday experience value I lack as a working mechanic a little. They develop a form on intuition instead that is priceless over the years.
The car gets a valve adjustment once a year. The last being less than 6 months ago. I average 15K miles a year.

What is this relief valve you talk of?
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1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge
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  #40  
Old 09-24-2013, 05:43 PM
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I was going to take the car into the tech session last Saturday at the MB dealership to address the IP timing but I had an opportunity to pick up a crack free dash and that took most of the day just driving.

I have half a mind to just go in there and line up the two marks and see what that does. My other 300SD has more Diesel clatter than the one we are talking about. The exhaust on the new car does not smell as rich, either.
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1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge
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  #41  
Old 09-25-2013, 03:33 AM
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Can some one please tell me how to do the minivolt meter test.
Where to hook up etc....
Thanks
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  #42  
Old 09-25-2013, 01:39 PM
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Can some one please tell me how to do the minivolt meter test.
Where to hook up etc....
Thanks
There is a long thread and plenty of information in the archives.
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  #43  
Old 09-25-2013, 02:02 PM
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Originally Posted by eatont9999 View Post
The car gets a valve adjustment once a year. The last being less than 6 months ago. I average 15K miles a year.

What is this relief valve you talk of?
It is a valve that feeds into the fuel return line from the injection pump. The internal spring and ball open at a preset pressure to keep the supply fuel pressure regulated in the injection pump.

With age the spring can get tired or crud can build up keeping it open. Ideal retained fuel pressure is 15-19 pounds by it. By design there should be enough fuel pressure supplied to enable it to overflow into the return line. It can be reconditioned instead of replaced by the owner if needed with the exception of the sealed later versions of it.

What I am feeling is to make sure you have decent fuel pressure. This based on the unusual fluxuations seen on the millivolt readings.. The exhaust smell could easily be some cylinders or all for whatever reason firing late.

Some of your readings indicated and should be double checked that you have unbalanced power strokes. Some readings also indicated they were okay at times. At least the valve clearances are out of the picture. Still something is going on.

Timing the number one element or at least checking it with the drip method should be attempted. I wonder what the fuel milage has been if known on that car?
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  #44  
Old 09-25-2013, 04:48 PM
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Quote:
Originally Posted by barry12345 View Post
It is a valve that feeds into the fuel return line from the injection pump. The internal spring and ball open at a preset pressure to keep the supply fuel pressure regulated in the injection pump.

With age the spring can get tired or crud can build up keeping it open. Ideal retained fuel pressure is 15-19 pounds by it. By design there should be enough fuel pressure supplied to enable it to overflow into the return line. It can be reconditioned instead of replaced by the owner if needed with the exception of the sealed later versions of it.

What I am feeling is to make sure you have decent fuel pressure. This based on the unusual fluxuations seen on the millivolt readings.. The exhaust smell could easily be some cylinders or all for whatever reason firing late.

Some of your readings indicated and should be double checked that you have unbalanced power strokes. Some readings also indicated they were okay at times. At least the valve clearances are out of the picture. Still something is going on.

Timing the number one element or at least checking it with the drip method should be attempted. I wonder what the fuel milage has been if known on that car?
Drip timing is still on the list of things to do. I think the car has close to 400K miles on it but it did not come with the original odometer. I'm judging this by the worn-smooth steering wheel and the steering gearbox that is ready to grenade any day now. The MPG is in the low 20's but I also drive it hard. She sees 4500RPM fairly regularly.
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1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge
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  #45  
Old 09-25-2013, 09:21 PM
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Well suspected higher miles just means more to check if the car was not well maintained over the years and has the same original engine. Using the milli volt method and some care can really keep the costs down as well.

You only land up doing what is indicated other than shot gunning with guesses. When the engine is timed right may tell a story as well. Personally I do not feel it is just the overall timing but after it is done will indicate something probably.

The fuel supply systems where in general not well maintained or even worked on unless the engine quit. At higher milages I would expect to find something not up to par there as well. Maybe not but it is a distinct possibility.

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