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  #46  
Old 01-04-2012, 12:24 AM
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Originally Posted by Beagle View Post
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That is incorrect!

It most certainly is possible and is part of the normal calibration procedure to set start of delivery on each individual cylinder within Spec.
Out of sequence would indicate it is injecting some where else before the prior injector or later than the next injector in the sequence. The range of adjustment of an individual pump element does not go that far I would expect. Slightly off sequential sequence is what you are reffering to I believe. To set the individual element to the exact centre point between elements with the right volume of output.

.The reason for the head removal is that the compression of the number two cylinder apparently drops with increased temperature. On the way in I would check the valve mechanisim very carefully on that cylinder. A jammed hydralic lifter at exactly the right point could enable this problem. It would have to be jammed at a very specific point where there was barely a valve seal when the engine is cold. So the valve is still sealing then. Again highly unlikely but it should not be ignored and only takes a minute to check out when the valve pan is off. I might even consider changing those two lifters depending on how I felt.

I also wondered about a bent valve stem dragging as the engine heated. The head would have to come of anyways if that was the case.

If I wanted proof the compression drops off below the ability to ignite the fuel at operating rpms. . Unless I could find a reason not too I might just leave the compression gauge hooked up in the injector port and run the engine. Releasing the accumulated pressure from time to time from the gauge to get a new indication. I have never heard of anyone doing this before and would have to really consider any possible consequences first. One possible complication is the valve stem heating with cylinder operation effect will be less. So that valve train has to be checked even before that approach.

So it is an approach that even though I might try it after a lot of thought I would not recommend it to another person. Remember since I am not a working mechanic I do not have the feel of enough experience or sixth sense type of thing that developes over time in the trade.

Thats why I never take an engine apart until I am pretty well absolutly certain of two things. Where exactly the issue is likely to be and what it is specifically if possible to establish. In this case I would want proof the compression is dropping below the ability to light fuel off. At this point it seems to be the most likely senario but not proven yet. Plus that valve train on that cylinder keeps erupting in my thoughts.

I cannot think of a senario where it is going by the piston. Other than some bizzare shaped cylinder that the piston changes its running position in after warming up. This is extremely far fetched though. The engine would have to have a history of blowing a lot of blowby and oil consumption as well I would think.

The other very important component of identification before head removal is when things are at room temperature with your engine everything is normal. Any effect of thermal expansion might not be evident. When apart you would be looking at many things with perhaps no indication of the problem being visiable. These heads crack between the valve seats usually. That means the coolant circuit has to be involved where yours appears not to be.

With this much air loss if the opening was to the coolant passages it would blow the coolant out of the system. If across a gasket missing all passages it should be evident on the edge of the head somewhere in the vicinity of the cylinder. Once again I am not a working mechanic though and that is very important as well.

Take seriously the working mechanics suggestions. They are safer to run with. You cannot beat years of steady hands on experience.

Last edited by barry123400; 01-04-2012 at 02:32 AM.
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  #47  
Old 01-04-2012, 12:38 AM
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Originally Posted by ChiefRider View Post
Great replies- lots to read and think about, Thank you!

The head comes off tomorrow.
Before you pull the head.
Call my cell tomorrow, you have a PM..
There is something very odd/missing in this diagnosis.


.
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  #48  
Old 01-04-2012, 07:40 AM
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First, Thank You- I will call later this morning!

This has been a most frustrating situation. I am primarily a gasoline guy, but I did have 10 years with a 240D, and I understand Diesel at perhaps the 50,000 foot range although with this I am learning more.

A couple details that may have been missed, although they do appear earlier in the thread.

When started, hot OR cold, the engine runs as it should for approx. 10 seconds, then starts missing and producing smoke.

At highway speeds the car appears to stop smoking, and seems to run smooth. My son followed me and said the smoke stopped, nor could I see any in the rearview. I don't believe this is due to more rapid disbursement, as there is simply too much smoke typically generated to account for that.

Also, a new but probably inconsequential detail. When the engine was reconditioned 40k ago, it also received a new turbocharger. On removing the turbo crossover pipe, a thin dribble of oil was found to have been traveling thru and draining primarily down intake tube #2. On the turbo side, we cleaned out a little gunk, but I attribute this to the fact that #2 cylinder has been passing fuel into the exhaust. Don't see how any of that would be a participant in this situation.

Lastly, the pertinent(?) info I have been able to get from the PO briefly stated:

He had a shop install new delivery valve seals. (I suspect they shouldn't have done the job, as they at least did not have the right tools, using either pliers or hammer and chisel to do the job. The splines aren't really messed up, but there are witness marks as to the incorrect tool use.)

Apparently unaware of a bad monovalve, he attempted to increase cabin heat by using cardboard behind the exterior grille, to reduce airflow. I don't know what coolant temp he was able to produce. One of his last repair tickets is for a new thermostat, with which he hoped to produce a higher operating temp. The engine runs at a stable 80c.

The engine uses no lubricating oil. This tends to assure me that it has good, cylindrical cylinders.

I can't wait till this is over. At least it should make for an interesting Diesel discussion someday.
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  #49  
Old 01-04-2012, 11:23 AM
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Ten seconds is a lot shorter time than I visualised. Running well for ten seconds when hot starting is another thing that was not known. Ten seconds is not what I really consider a warm up time. Once up to operating temperature I also would have not expected that engine to somehow restore compression on the restart.

This might change things. Or may not. I would tread more cautiously now. Using the non spline tool to do the delivery valves raises questions as well. I could go back through the thread. Was the problem there when you purchased the car?

If this were my car I would do the compression gauge left hooked up to the injector port test unless I could figure out a negatiove consequence of doing it.
It would give me proof the pressure is falling below the compression/ ignition point of the fuel or not. After removing the injector and before hooking up the gauge. I would crank the engine over to eliminate any possibility of residual fuel in there. Or the help of the drain down oil. I would not want the cylinder to fire even once.

The ten second run may also be being enabled by the drain down leakage from the turbo you noticed draining down the number two runner with the engine off. . The connecting tube from the turbo I would disconnect for testing as well.

Starting the engine a few times with it off and letting it sit between startup times. If this is a source of fuel or enabiling enough compression it or the possibility has to be eliminated. You would not want even one power pulse from that cylinder to occur with the gauge hooked up.

I would like other members to kind of endorse the ideal or post a reason not to do it first though. I have not totallly thought this approach through. Superficially I do not see one yet could easily miss something.

Last edited by barry123400; 01-04-2012 at 12:14 PM.
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  #50  
Old 01-04-2012, 12:00 PM
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By the way I separated this because it might be important. The reason the compression reading might be higher cold than after a start up and recheck hot. That oil coming down the intake runner tube may have accumulated over the time sitting raising the compression by decreasing the volume of the cylinder. Or even just sealing the rings better.

After the engine has run and cleared the cylinder and rings of it the compression would be lower. Possibly just the rings are not coated with the draining down oil. There has not been enough time for the turbo leakage to accumulate in the cylinder again. Just a speculation though.

Another simpler test may be to remove the turbo connecting tube. Start the engine several times with a decent period between start ups. Will the engine now still start on all cylinders? Still running for the ten seconds? This I would do prior to the running pressure gauge test anyways. This cylinder may not really have enough compression once the drain down oil effect has stopped to run.

I almost feel like I am out on a limb with a grasp on the branch and the other hand has a saw in it. Your difficulty might ultimatly indicate a preventative check on the three point fives. Most the reported issues have been towards the front of the engine with the number two cylinder involved.

It has always bothered me that the europeans have always said it is not a problem over there. I assume the european models have a turbo as well. I now wonder if it is by the same manufacturer.

Well it is a little early for this type of speculation until your issue is conclusivly identified. Over the long haul your problem may have helped many. Time will tell.

Last edited by barry123400; 01-04-2012 at 01:16 PM.
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  #51  
Old 01-04-2012, 02:26 PM
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First, thanks to forum member whunter for a great conversation about this problem. Analyzing the hard evidence, and speculating based on circumstancial evidence, the course of action now is to remove the IP and have its calibration and operation checked and set as appropriate. I was able to find a diesel injection shop where the tech is very experienced with this pump, has all the right equipment and will approach the corrective actions a la carte. The pump should be off the car tomorrow, and to the shop asap.

A couple things to address for member Barry. I should probably time the ten seconds, I haven't. It is long enough to lull you into a false hope that it will keep right on running well. The problem begins with a distinct misfire, then another and the shaking and smoking begin.

The oil in the crossover tube is, I believe from the fuel in the exhaust. There wasn't much, but we did clean it out and run the engine a few times after, with the crossover tube off. No change.

I really appreciate all the time everyone puts into thinking and reasoning out unusual problems like this. The collective knowledge here is tremendous. I'll keep you all informed about my progress!
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  #52  
Old 01-04-2012, 02:35 PM
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Thanks for posting the update and keeping us up to date. This particular problem is interesting to say the least.
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  #53  
Old 01-04-2012, 05:14 PM
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Originally Posted by ChiefRider View Post
First, thanks to forum member whunter for a great conversation about this problem. Analyzing the hard evidence, and speculating based on circumstancial evidence, the course of action now is to remove the IP and have its calibration and operation checked and set as appropriate. I was able to find a diesel injection shop where the tech is very experienced with this pump, has all the right equipment and will approach the corrective actions a la carte. The pump should be off the car tomorrow, and to the shop asap.

A couple things to address for member Barry. I should probably time the ten seconds, I haven't. It is long enough to lull you into a false hope that it will keep right on running well. The problem begins with a distinct misfire, then another and the shaking and smoking begin.

The oil in the crossover tube is, I believe from the fuel in the exhaust. There wasn't much, but we did clean it out and run the engine a few times after, with the crossover tube off. No change.

I really appreciate all the time everyone puts into thinking and reasoning out unusual problems like this. The collective knowledge here is tremendous. I'll keep you all informed about my progress!
Don't forget the pictures I requested, BEFORE it is re-calibrated.


.
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  #54  
Old 01-04-2012, 07:47 PM
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I'll post the pics later this evening.

There is nothing like a good story, right? Always a new twist or turn. Well, here is the latest.

I called the PO this evening in an effort to get some clarification on the engine rebuild, and the history of the problem. Interestingly, now that I own the car, there were far more details available.

The car was purchased with the engine seized from the oil pump. Engine was rebuilt as previously outlined. I was told that the cylinders all showed nice cross hatch, and were given new rings. According to tonite's discussion, the engine smoked right after the rebuild, and cyl #2 was found to have low compression (this would have been nice to know). Apparently, it had the same symptoms then as it does now. The shop that gave the low comp diagnosis also replaced the delivery valve seals at this time. PO drove the car like this for a couple hundred miles, and had the new head installed. Same problems so he contnued to use it, racking up 30k miles on the engine running exactly this way. Interestingly, this would seem to exonerate the cylinder head as a factor.

He did say that the warmer the weather (or engine temp) the less the problem, and as I have observed, at high speed it seems to run ok. He also told me that the shop that installed the newly rebuilt engine spent some time trying to de-glaze the #2 cylinder in an attempt to improve compression.


I have no idea if any of this is really germain. The comp test values still seam to indicate to me combustion should be taking place, and I have no idea how the engine ran prior to the oil pump issue. My indie tells me that the delivery valve nozzle for number 2 is damaged, so that is encouraging!
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Last edited by ChiefRider; 01-04-2012 at 08:40 PM.
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  #55  
Old 01-04-2012, 11:07 PM
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I think somewhere earlier in this thread I mentioned something about the afterglow allowing the engine to run smoothly initially after which the compression issue rears its ugly head as a result of the glowplugs no longer helping with combustion,,, maybe I wasn't succinct enough.

After your latest confab w/PO. I would be looking for another engine entirely. Love how the info comes out after the deal has been done. If it makes you feel any better I have been there as well. Sucks to be a trusting individual in a lot of ways these days.
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  #56  
Old 01-04-2012, 11:26 PM
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I did catch that about the glowplug, and it does coordinate rather well.

And yes, the info I got prior to the sale was a bit obtuse. I even considered that at the time, but my purchase price was quite low for what otherwise is a really nice car. If I did have to source another engine, I'd still be okay installing a 3.0.

Here is a photo of the injector pump, whunter. PM me with your email if you would like me to send additional views!
Attached Thumbnails
Intro and First Question:  Engine Starts Smooth, then Runs Rough-injectionpump.jpg  
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  #57  
Old 01-19-2012, 03:46 PM
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OK, the saga continues.

I brought the injection pump to a great shop, Metro Fuel Injection in Deep River, CT. Steve the technician was very knowledgeable and did a nice job on the pump, telling me what he found, and what needed to be done. He replaced one stub pipe to fix a leak at the hard line for cyl #3. He also replaced the element on number 5, having found that someone had damaged it in the past. It is now repaired, calibrated and fit for service.

Just one problem: There was nothing wrong with the pump regarding cylinder #2.

So the plan is this: Reinstall pump, and hope that #2 comes to life. I don't think that will be the result

By process of elimination I'm down to the sleeve / piston for #2. Breif summary- After the engine rebuild, engine ran is it does now, low comp. on #2. Brand new #20 head installed, no change. I have confirmed that it is not an injector problem, and I don't believe it to be the piston, as the problem existed right after rebuild.

When the engine runs as I expect it will, verifying it wasn't the pump, then the head comes off in order to measure the bore on number 2 and see what I find.

I guess this is the $64 question: Should I install a new sleeve for #2, or just find a 3.0 litre short block? This engine has a pretty fresh reground crank and bearings, and the other 5 cylinders are ok. Of course, I haven't seen any 3.0 litre blocks sitting around either.
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  #58  
Old 01-20-2012, 03:35 PM
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A couple pics of the injection pump before installation. It is sitting on the desk at my indie's shop almost ready to go back under the hood.

Most injection pump shops are only interested in a full tilt rebuild, running about $1000.00. I was very pleased to find this shop, formerly H&L Fuel Injection, now a Metro Fuel Injection shop in Deep River, CT. Steve, the tech that did my pump was great in working with me on just what needed to be done. He cleaned and inspected the pump prior to setting it up on the test stand. Next he made the appropriate repairs, calibrated and ran the pump. It now has a perfect bill of health, for about half the price I would have paid elsewhere. It was interesting to note the red dots that have been applied to a variety of screws and seal joints verifying no one goes in there and messes anything up.


Metro Fuel Injection
(formerly H&L Fuel Injection)
500 Main St
Deep River, CT
Phone: 860-526-5941
.
Attached Thumbnails
Intro and First Question:  Engine Starts Smooth, then Runs Rough-photo0064.jpg   Intro and First Question:  Engine Starts Smooth, then Runs Rough-photo0067.jpg  
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Last edited by whunter; 01-21-2012 at 05:44 PM. Reason: Contact data added
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  #59  
Old 01-20-2012, 06:21 PM
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At this point it might actually be worth it to pull the motor and have a trusted machine shop deal with cyl 2. However you will essentially be paying for another rebuild as any good machine shop will want to and should in fact double check everything else to cover themselves and you as well.
Is the rest of the car perfect? You now have a good head and pump which is 2/3rds of the battle.
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1978 300CD auto
1985 300D auto
1983 300TD auto
1984 Porsche 944 5 speed
1973 Opel GT 1900 4 speed
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1973 Mustang Grande Convertible 302 C4
1981 VW Pickup 1.6D Turbo 5 speed
1983 Rabbit 1.6D Factory Turbo 5 speed
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  #60  
Old 01-20-2012, 08:34 PM
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The rest of the car IS perfect (well, really nice). Tires, exhaust, suspension, brakes, radiator, transmission and more all brand new. Interior and exterior 8.5 out of 10, zero rust.

Once the pump is installed, I'll assess how it runs and go from there. If cylinder #2 wakes up, great. IF not, I'll pull the head and inspect the bore, and sleeve if needed. One way or the other, it should be a great running SD when done!
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