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  #16  
Old 09-13-2011, 02:50 PM
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smoke gets in your eyes
 
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Crack each injector line while idling to see if it's a problem with one or all cylinders.

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  #17  
Old 09-13-2011, 04:28 PM
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I tried that

I loosened each injector and watched the result, it was the most even drop in rpm I have ever seen on any diesel I have done this to . At this point I am going to focus on a pluggage in the exhaust somewhere as I have more or less examined the intake thoroughly for blockage. My working theory is they screwed up the trap ox replacement by allowing something like insulation or gasket to get into the pipe or turbo, I was blown away do see that this was done on a recall of a 20yr old vehicle at no charge. Front to back exhaust replaced as well as new turbo!! I will also try to see if the turbo is plugged up with carbon. Cheers Dan
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  #18  
Old 09-13-2011, 04:46 PM
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smoke gets in your eyes
 
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There's a plug on the #1 exhaust runner. Remove it and see if you get the same smoke.

There's a quick way to check IP timing. Set the crank pulley to 15* ATDC and check the timing lug in the IP. It should be at or close to centered in the port.



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87 300D
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  #19  
Old 09-13-2011, 09:10 PM
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Timing questions

When we attempted to duplicate the appearance of the timing mark in the window what we got was 10 deg before TDC.
The alignment pointer is directly below the engine shock if we understand correctly.
When we tried setting the pulley at 15 deg Atdc the mark was no where to be found.
Would the engine even run 25 deg advanced or did we do it wrong.
It seems that the adjustment bolt will only go a few degrees in either direction if the 3 IP securing bolts are slacked off.
So did the timing chain slip or was the pump installed wrong 1 or 2 teeth out. With virtually no history it is difficult to tell if the previous owner had any idea how it was supposed to run.
What is the next step in verifying the timing. ?
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92 Toyota Diesel Landcruiser HDJ81-t 116K
02 Golf TDI new head courtesy of PO
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97 BMW 525 TDS Wagon 5spd
bunch of Onan and other diesel generators
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  #20  
Old 09-13-2011, 09:26 PM
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smoke gets in your eyes
 
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There's a 4th IP bolt at the tail end of the IP. Loosen the horizontal bolt (13mm wrench) into the IP, not the two bolts into the block.

This is the best picture I can find of the crank pulley indicator. It's the brass thing under the water pump. This angle doesn't show the pointer that extends horizontally over the damper but you can see its shadow at about 11 o'clock from the crankshaft. You must have seen it if you saw the 10* BTDC mark.



Mind you, that bracket with pointer is adjustable. MB in its infinite wisdom decided someone ought to pull a prechamber and directly verify TDC. Why they put timing marks on rubber is beyond me.

I don't think there's enough IP timing adjustment range to restore a 35* offset. Either the chain skipped several teeth, someone didn't install the IP correctly or the timer is jammed in an advance setting. Unfortunately the advance mechanism on the hidden side of the timer so just pulling the vacuum pump isn't enough. On the other hand there's little else to do but lift the chain and remove the timer once the vacuum pump is off.

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  #21  
Old 09-13-2011, 09:27 PM
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If the cam marks line up with the crank, then there is no real way to know without opening the engine to look for for broken parts.

I would re-install the IP correctly if you are certain that it is wrong.

The engine will run... and be difficult to start.

The next step would be to rent a special MB tool for timing this pump. RIV or A-B lights. I think MBDoc has one for rent, maybe Billybob.
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  #22  
Old 09-13-2011, 11:21 PM
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I may have been using the wrong pointer

I will have to check that what I saw was the actual timing pointer not something else. I will also pull the valve cover to verify the cam timing. This is a bit of a learning experience for me. Cheers Dan
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91 300D 603.960 (from japan) 194K
92 Toyota Diesel Landcruiser HDJ81-t 116K
02 Golf TDI new head courtesy of PO
87 300D
97 BMW 525 TDS Wagon 5spd
bunch of Onan and other diesel generators
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  #23  
Old 09-14-2011, 03:38 PM
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Bypass the check valve from the alda vacuum line to the manifold. Also ream out the manifold vacuum port. These engines should have plenty of power to handle any hill. When the check valve gets plugged the power goes away and the black smoke comes on.
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  #24  
Old 09-14-2011, 05:07 PM
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Wish me luck

I have decided to buck off the exhaust under the car in front of the transmission bracket at the back of the trans. This will take the suspect section out of the picture. This particular exhaust system has three items in line the rear is obviously the muffler the middle one is a resonator and the front one attached to the piece just back of the manifold is, I am guessing, a cat or trap ox of some sort. It does not show up in any of the parts diagrams or lists I have seen. It is quite small so if it has the typical honeycomb inside it it could plug up easily with carbon. If I cut the pipe ahead of this temporarily I should be able to eliminate the backpressure it may be causing. It is a quick test in any case. I will also continue with verifying the timing, I must have been looking at the wrong pointer, I can't see the engine running at all with the timing 25 deg out. Cheers Dan
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It's always something simple
91 300D 603.960 (from japan) 194K
92 Toyota Diesel Landcruiser HDJ81-t 116K
02 Golf TDI new head courtesy of PO
87 300D
97 BMW 525 TDS Wagon 5spd
bunch of Onan and other diesel generators
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  #25  
Old 09-14-2011, 05:15 PM
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Can't you get a rough judgment about whether the exhaust is plugged by watching the exhaust pipe as you start it and comparing it to a known good similar vehicle?
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  #26  
Old 09-14-2011, 11:20 PM
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I think I made some progress

I cut the pipe & extended it with a piece of drain pipe. Still smoked like h__. I removed the small plug at the #1 exhaust port and removed the flex section going to the egr. Still a bit of smoke at idle but it cleaned up when the revs are raised. This is the first positive sign I have had. Tomorrow I will remove the section from the rear end of the manifold going into the turbo housing so the turbo will no longer be in circuit. It is looking like something is funny with the turbo I did check the timing and concluded we were looking in the wrong place for the timing indicator. If we understand it correctly the timing is viewed in the small round window of the sheetmetal bracket bolted to the front of the engine at about 10 oclock . When viewed through this the IP tab is centered in the plug hole on the side of the injection pump. More tomorrow. Cheers Dan.
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It's always something simple
91 300D 603.960 (from japan) 194K
92 Toyota Diesel Landcruiser HDJ81-t 116K
02 Golf TDI new head courtesy of PO
87 300D
97 BMW 525 TDS Wagon 5spd
bunch of Onan and other diesel generators
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  #27  
Old 09-14-2011, 11:23 PM
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Once again I suggest testing boost pressure. That will tell you a lot and will give you a reference point for later!
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  #28  
Old 09-14-2011, 11:36 PM
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I will

Once I get it back together I should be able to drive it on the street. Up to now the smoke was so bad I pretty much couldn't do anything except start it for a minute or two before I had to shut it down. I will probably have to remove the turbo to inspect it once I finish diagnosis and fix whatever I find. At that point I will test the boost and acceleration to get a baseline. I am anxious to get it cleaned up as I don't want to attract attention and get a VI ticket (vehicle inspection). They are way too zealous when they pull you over. Cheers Dan
__________________
It's always something simple
91 300D 603.960 (from japan) 194K
92 Toyota Diesel Landcruiser HDJ81-t 116K
02 Golf TDI new head courtesy of PO
87 300D
97 BMW 525 TDS Wagon 5spd
bunch of Onan and other diesel generators
Reply With Quote
  #29  
Old 09-15-2011, 03:34 PM
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Bypass the vacuum check valve on the firewall.
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1987 300TD 440K - My car
2005 Jeep Grand Cherokee Laredo 107K - Tim's car
2000 - CLK320 100K - Deb's car
1994 C230 150K - Josh's Car
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  #30  
Old 09-24-2011, 01:45 AM
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Thinking the timing device is frozen.

At idle the smoke is still bad. When you rev it the smoke cleans up. If the timing device was screwed up it would not have the correct timing at idle only when you revved it. Is this a logical statement? I want to make sure I understand where the timing marks are viewed from. The degree marks on the flywheel should be set in the centre of the round window in the sheetmetal bracket bolted to the front of the engine cover at approximatley the 10oclock position facing the crankshaft. When this is done the timing tab on the IP should be centred in the port on the side of the IP which usually has a threaded plug in it & is removed to see the tab. Do I understand this correctly?. So if my concept is correct then the timing is advanced at idle due to the failure of the timing device. In order to test this theory I would like to rotate the IP approximatley the same number of degrees as the timing device is out. this should clean up the idle. so which direction should I turn the IP body to temporarily correct the idle timing. I did try a set of known good injectors lent to me by a friend. I also disconnected everything on the intake side up to and including the intake manifold as well as the turbo inlet from the exhaust manifold. The result was still the same black smoke at idle cleaning up when revved.. My reasoning tells me that nothing in the way of sensors or valves could affect the mixture under these circumstances. Only the internal engine components would still be in play ie the IP , timing chain, timing device and injectors. Is this correct? Cheers Dan
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It's always something simple
91 300D 603.960 (from japan) 194K
92 Toyota Diesel Landcruiser HDJ81-t 116K
02 Golf TDI new head courtesy of PO
87 300D
97 BMW 525 TDS Wagon 5spd
bunch of Onan and other diesel generators
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