IMHO, the obvious lack of movement is a strong indicator that the rubber mounts have hardened with age and/or exposure to petrochemicals from the engine. I have little doubt that you will never regret changing out motor mounts on a diesel engine unless they are less than 5 to 8 years of age!
Regards,

Gene,

In the end I improved my issue a lot by getting a new rack damper pin, rebuilding injectors and adjusting my timing.

But, the heart of the issue is that two of my cylinders are low on compression. #4 is about 220psi, and #5 is about 260psi. I think that is what causes the issue. Since the two cylinders fire later than the other three, it unbalances the whole thing. Its not bad, just a gentle shake at idle that I have now grown accustomed to.

Like yours, the car runs like a scalded dog, doesnt smoke much, sounds great, gets 25-26 mpg highway and even starts when its cold after a couple glow cycles.

You have a bunch of stuff to check over, but just to let you know that can be the issue. A compression check could tell you a lot...

That being said, i learned a lot about the car chasing this one down :-)

dd

__________________
-------------------------------
'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car

I'll try the compression test next. I assumed compression wasn't an issue with this engine as it fires up immediately even when cold after a single glow plug cycle.

Any recommendations on a pressure gauge? It's probably been over 20 years since I did one, it was on an old low compression gasoline engine, and IIRC had just a rubber tip that you pressed into the spark plug cavity. I am assuming that you would need a model that can be threaded into the injector plug cavity. A search for "compression test" does not appear to reference any detailed how-to instructions, just results.

On that matter are there any caveats on removing the injectors?

Edit: Well, that was incorrect, sort of. Finally found some apparent information here and here . There was conflicting information but it appears that you can buy a tester from NAPA that has adapters that will thread into the glow plug holes. I'll stop by there in the morning.

Sam I think they mean the mechanical advance timing unit situated in front of the pump but I am not absolutly certain. I think I have heard it reffered to as the timer.

For doing your compression test, you will need an adapter with a 90 degree swivel which can be used in the injector or GP hole. I got mine from "Eppy Tool",Brookklyn, NY . The "Snappon" guy used to carry them but no more

I use the GP hole because pulling injectors means new return line and replacing the heat shield.

__________________


1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

Gene,

The diesel engine compression testing kit sold by Harbor Freight tools is what most folks use. Thats what I have since i hopefully wont be doing many compression tests. I got mine for $30. Instructions are included with the kit. There are instructions on the forum, I had to dig a while to find them.

Basically you take the injectors out, attached in the compression gauge and crank the engine over 7 or 8 times, then check the reading. Its easy to do.

I tested through the injector holes, this seems to be the easiest thing to do to me. Some suggest testing through the glow plug holes.

dd

__________________
-------------------------------
'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car

The problem was as I originally suspected - the rack damper bolt. Instructions for all of this are a bit, ah, lacking and so I will post my steps for inspection.

You'll need a 14mm and a 12mm wrench. The 14mm for the locking nut and the 12mm for the bolt itself. The bolt has a spring loaded pin on the tip. This is what provides the damping.

1) Loosen the lock nut. In my case it looked like it was all of the way back and so I had backed the bolt out a little to loosen the nut. It winds up that in my case even though the bolt looked like it was all of the way in to the eye there was actually a couple of mm gap.

2) The oil filter cannister allows you to only turn the wrenth in 30 degree increments. And there isn't room to get a socket on it. But taking off the filter would take more time than you would save by being able to use the socket and so just bear with it. It isn't held in by a large number of threads (5 or 6?). The bolt isn't very long.

3) I was worried about oil pouring out but less than a teaspoon ran out. A few paper towels will keep things clean.

4) I had one of the new design "gold" (brass?) bolts. The plunger spring appears very good. It takes a few pounds of force to push it in. If it is loose (or if the plunger is frozen) it may be time for a new bolt.

5) I inspected the O-ring. The threads on the bolt have a gap and I assume this is where the O-ring sits. The O-ring was flattened. I reused it for the running test but will purchase a replacement.

6) You have to use a little bit of of pressure to get the bolt started when putting it back in. Fingertip pressure but it is a bit awkward at the angle where it sits. Since these are metric threads/a little finer than people may be used to you have to use the proper method to avoid cross threading. Push the bolt in, rotating it counterclockwise as if you are removing it. You'll feel it "click" when it reaches the end of the thread. At this point then reverse direction and it should engage smoothly.

7) I was able to hand thread the bolt in until I started feeling a little resistance. At this point it looked like it was almost all of the way in. I gave it about 1/4 turn more, locked the locknut, and started the engine. The engine almost ran too smoothly. Purred like a kitten. Took it for a short drive to get it to operating temperature. It got a little rougher running but I can't feel anything inside the cabin. Night and day compared to before.

I still plan on testing the compression and fuel pressures just to have additional data but at this time they appeared completely unrelated to the symptoms I described earlier.