True and very true! I actually quit trying on the 4th bolt (back by the rear of the pump) after realizing there's no way I'm going to get to it without the intake coming off. I figured the IP wouldn't move without it being loose, but the adjuster bolt moved the IP with almost Zero pressure. I don't think the dealer loosened the 4th bolt when they timed my car a while back because they only charged me $100. The intake coming off would be more in labor fees than that I'd think.

__________________
-E300d '99 350k
-Suburban '93 220k
-TDI Jetta '03 350k
Sold
-F250 '96 7.3
-Dodge Ram 12V
-E320 '95 200k
-E320 Wagon 1994 155k
-300d Turbo '87 187k miles
-E320 1994 200k
-300d Turbo '84 245k (sold to Dan62)
-300d Turbo '84 180k
-300sd '80 300k
-7.3 Powerstroke Diesel 15P Van 500k+ miles
-190d '89 Non Turbo 2.5 5cyl 240k (my first MB)
Tom's Imports of Columbia MO Ruined the IP in changing leaky delivery valve O-Rings - Refused to stand behind his work. Mid-MO MB drivers-AVOID Tom's.

still seems to be an improvement. I am going to retard it a hair more when I get time. I really think it was advanced a good bit more than the dealer who A-B time light checked it thought. The pop pressure of the injectors was a little lower than FSM spec so I'm guessing that advances it a hair.

__________________
-E300d '99 350k
-Suburban '93 220k
-TDI Jetta '03 350k
Sold
-F250 '96 7.3
-Dodge Ram 12V
-E320 '95 200k
-E320 Wagon 1994 155k
-300d Turbo '87 187k miles
-E320 1994 200k
-300d Turbo '84 245k (sold to Dan62)
-300d Turbo '84 180k
-300sd '80 300k
-7.3 Powerstroke Diesel 15P Van 500k+ miles
-190d '89 Non Turbo 2.5 5cyl 240k (my first MB)
Tom's Imports of Columbia MO Ruined the IP in changing leaky delivery valve O-Rings - Refused to stand behind his work. Mid-MO MB drivers-AVOID Tom's.

Well after all kinds of searching:
Injector Pop Testing, looking for leaks, retarding my timing etc... etc... I finally cured the shake at idle in my 87 300d.

This thing on a long trip when the engine is good and hot would shake so bad at idle that my knees would move a good 2 inches left and right. At a cruising speed it was fine. Just idling.

I thought I was going to have to have the injection pump rebuilt!

FINALLY figured it out. I had read the 603's IP is just not as stout as the 617... that didn't make sense to me because component wise it's very similar. Also I'd heard the Cummins 12 Valve trucks from 94-98 with the inline pump (much like ours) would last 800k and more before rebuild. So to think mine needed to be rebuilt really had me bummed out.

Anyways, after all this I ended up having to take my IP out anyways because I created an oil leak between the pump and the block (o-ring) while adjusting the timing. So out it came (see the pictorial I did a while back).

But while it was out I decided to change all the seals (bottom o-ring, side plate rubber gasket, ELR O-ring, the back plate gasket, as well as the Fuel delivery valve o-rings and copper washers).

The only ones out of that AFAIK that have anything to do with fuel delivery are the delivery valve o-rings. So at this point I'm thinking that had to be it.

If your engine shakes at idle and is a 60x (300d '87-94, E300d '95-99, '86-?? 300SDL) I would bet money that it's your delivery valve o-rings.

I didn't see ANY sign of leaking but when they were removed they were flat and hard as could be. I'm amazed they weren't weeping. At the high delivery pressure of the injectors probably just a little bit of leaking pressure makes a big difference at idle. I haven't confirmed this twice yet but I think I've also broken the 30MPG marker (hwy)!

So... this has been a great fix. I've been wondering what it was for a long time. From now on I'm not going to let anyone tell me the 60x injection pumps are not as good in quality as the 61x IPs. But I guess they do have one thing on us... 61x's didn't have o-ring seals at the delivery valves.

Anyways, I've now confirmed with an 8 hour drive (very hot today at 107F) that the shakes are now gone after my o-ring job.

Buy the splined socket, buy the viton o-rings from JADAVIS on the forum and do the job if you haven't. The www.DieselGiant.com tutorial is a pretty good step by step if you're confused about it.

One thing I will recommend is to remove the splined locking colars (keep the Delivery Valves from turning when you tighten or loosen the injector lines) before cleaning the top of the IP because under them is more crud. I used brake cleaner (2 cans) and a nylon brush to remove the gunk before I did the job. Clean is important.

__________________
-E300d '99 350k
-Suburban '93 220k
-TDI Jetta '03 350k
Sold
-F250 '96 7.3
-Dodge Ram 12V
-E320 '95 200k
-E320 Wagon 1994 155k
-300d Turbo '87 187k miles
-E320 1994 200k
-300d Turbo '84 245k (sold to Dan62)
-300d Turbo '84 180k
-300sd '80 300k
-7.3 Powerstroke Diesel 15P Van 500k+ miles
-190d '89 Non Turbo 2.5 5cyl 240k (my first MB)
Tom's Imports of Columbia MO Ruined the IP in changing leaky delivery valve O-Rings - Refused to stand behind his work. Mid-MO MB drivers-AVOID Tom's.

SOLVED! See my other threads (around this date range) or just to cut to the chase, delivery valve o-rings. I've driven it on long hot drives (8 hours for a trip today) and NO MORE SHAKES! This things as smooth as a gasoline engine again!!! It even sounds better. Now I know what the 603 was like when it was new. I haven't confirmed this twice yet but calculated on one fill up and I'm pretty sure I got 30MPG today! The highest before was 28. A touch more power as well!

__________________
-E300d '99 350k
-Suburban '93 220k
-TDI Jetta '03 350k
Sold
-F250 '96 7.3
-Dodge Ram 12V
-E320 '95 200k
-E320 Wagon 1994 155k
-300d Turbo '87 187k miles
-E320 1994 200k
-300d Turbo '84 245k (sold to Dan62)
-300d Turbo '84 180k
-300sd '80 300k
-7.3 Powerstroke Diesel 15P Van 500k+ miles
-190d '89 Non Turbo 2.5 5cyl 240k (my first MB)
Tom's Imports of Columbia MO Ruined the IP in changing leaky delivery valve O-Rings - Refused to stand behind his work. Mid-MO MB drivers-AVOID Tom's.

On my 240D a loose DV (only finger tight) was causing a misfire and I read that what happens is on the downstroke the plunger draws a small amount of air in around the DV base and the small volume of air is enough to cause the fuel in the hardline to not pressurize enough to pop the injector at idle.

Basically at speed this can be overcome by the increased volume of fuel or just the misfire is less noticeable but at idle the air in the hardline is enough to prevent the fuel from pressurizing to pop open the injector. I'd bet the same thing can happen in the 603/606 pumps if the seals are bad - that air can be sucked in and cause micro-bubbles in the fuel which prevent it from pressurizing when the DV plunger goes up.

In any event I can tell you that simply tightening the loose DV on my IP cured the miss (and the rocking at idle) and now the car is firing on all 4 cylinders all the time

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

Ahh!! And I'd bet this would be why I didn't see an actual 'Spilling Fuel' type leak that some people have with leaking delivery valve o-rings. It makes sense.

I'd also bet that with the down-stroke the plunger is, as you said, 'drawing in air' and as it pressurizes in the upstroke (compressing the fuel) I'd bet it's pressing the o-ring back in place so it won't leak fuel.

That's gotta be what was happening. I can totally picture it now. Thanks for the input!

__________________
-E300d '99 350k
-Suburban '93 220k
-TDI Jetta '03 350k
Sold
-F250 '96 7.3
-Dodge Ram 12V
-E320 '95 200k
-E320 Wagon 1994 155k
-300d Turbo '87 187k miles
-E320 1994 200k
-300d Turbo '84 245k (sold to Dan62)
-300d Turbo '84 180k
-300sd '80 300k
-7.3 Powerstroke Diesel 15P Van 500k+ miles
-190d '89 Non Turbo 2.5 5cyl 240k (my first MB)
Tom's Imports of Columbia MO Ruined the IP in changing leaky delivery valve O-Rings - Refused to stand behind his work. Mid-MO MB drivers-AVOID Tom's.

I still think something else may contribute to it. But its hard to say, I want to have my IP bench tested.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200