Ive been working on a 84 300sd with around 270k on it. It had a bad shake at idle so I did the following:

-New fuel filters
-new injectors (pop'd and balanced)
-oil change w/filter
-new timing chain with new tensioner
-valve adjustment
-new rack damper pin (updated gold one)
-diesel purge
-new motor mounts
-new motor shocks
-new belts

OK so I still have a 'moderate' shake at idle. I was hoping the timing chain would have fixed it bc it had around 8* of stretch. I doesnt shake when its warming up but when its at proper operating temp.

Things I am thinking of doing next: Which ones do you think I should do first?

-remove the 'aftermarket' K/N intake and put the old air box back on
-IP timing
-swap out IP with another IP with 167k miles on it
-clean fuel tank screen
-find a new motor!
-junk the damn thing

Any help as to what to do next would be appreciated... I am starting to get frustrated with the shakes!

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Have you spent the time to tune the gold pin? It's not just a simple matter of threading it in place and letting it go at that. There is a sweet spot where the rack is sufficiently damped but the cold start is not affected.

I'd thread it in one more turn and test it for a week or two. Then report back with results.

^^Agreed, I have had to do that.

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83 SD

84 CD

Ive done that several times. I am about a half thread turn away from being flush against the large bolt against the IP. If I back it out just slightly the motor starts rockin. Turning it the last half thread makes no changes. This is why it leads me to believe the IP is shot. I think the PO may have run some sort of veg oil mix.

Any other ideas?

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Timing the IP sounded like a good idea.
If you have another IP you could swap it as you said.

Since it has 270k and you are not sure of what the PO did or did not do maybe a compression check might give some more info.

Also on mine I need to keep the idle speed at least at 750 rpm or it shakes more.

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84 300D, 82 Volvo 244Gl Diesel

Yes, unfortunately, you might have reached the end of the capability of the pin.

If you're positive that none of the injectors are the culprit.........poor balancing being the first suspect.........you're probably out of options.

However, one last possibility that you should check out are the engine shocks. If they are collapsed, they can allow most of the five cylinder vibrations into the frame. The problem should also be present when cold, however, so I'm not all that optimistic about success with this approach.

I've been down this shaky road.

Check the compression of each cylinder next. That will tell you a lot. If it is even across the five, then you know it must be something else. If one or two adjacent ones are low, then you have your answer.

I had the same issue on my '82 (nice massage, but not horrible). Did a compression test and found 380-370-380-260(260 w/oil squirt) -240 (260 w/oil squirt ).

dd

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'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

Its always a minor air leak.use german clamps,and clean the screen.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

minor air leak? I am not sure what you mean. Do you think I should change out the cigar hose fuel return pipe and change the fuel pipes by the tank? They look original but by no mean leaking or 'soaked'. I will tackle the tank screen when I burn some diesel off.

Do you guys think an air leak due to this would cause the shaking? I just did the timing chain.. how much harder would it be to swap out the IP? I should probably try the IP timing first?

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and Ill do the compression test as well.

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I've had the exact same issue for some time. Engine is smooth when cold and shakes horribly when hot.

Valve timing has been set - was only slighly tight on two of the valves. IP timing was only 1 degree off. Engine starts immediately when cold. Compression is good on all cylinders. New style (gold) rack pin and the springs are very good. All new filters. Engine mounts are in great shape.

The specific case of only shakes when hot seems to have a cause outside of the usual suspects.

The next two items on the list to check are to test the injectors and try grinding down a little off of the gold rack damper bolt nut to allow it to be screwed in a little further (recommended by a member of this board).

Don't get frustrated when/if all of the suggestions don't fix the problem. Most of these are annual tuneup items and should be done anyway.

I also had the above happen. The hoses was hard and tightening the clamps did not help. When it was good and hot under the hood I found I could rotate the plastic filter inside of the clamped hose.
Replacing the Fuel Inlet Supply Hoses did get rid of a little shaking.

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84 300D, 82 Volvo 244Gl Diesel

You could just idle it up a bit and live with it.

True. On my vehicle the shake goes away a little above 900 rpms and there doesn't seem to be a material additional strain on the drivetrain when stopped.

I've had air leaks where no diesel leaked.I order the german clamps,as the others cut the hose.Anytime I change primary,I cut off some hose to get tight seal.So I make my hose longer from tank,and longer from lift pump.This way I can trim ends.It does not matter about cigar hose unless dripping bad.I also put a little oil on large fuel filter gasket.
The primer pump is also a place where air leaks come from.
Make sure to no tight valves.
Also when fuel screen is clogged you will get the shakes,I removed mine cleaned it.I took a razor and cut at the top,so fuel can get thru.I run a less finer fuel filter before primary.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran