It's looking more and more to me as if there is a problem internal to the IP. You need to talk to someone familiar with the internals of the IP who has an hypothesis about what might be broken.
Before doing that, maybe it would be wise to check the fuel pressure from the lift pump to the IP to exclude a lift pump failure as the cause.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

What Kerry said.

It's highly unusual for the lift pump to fail (except on cars run on bad WVO) but highly unusual doesn't equal impossible.

It is really sounding like a lift pump failure or a more serious internal failure in the pump.

Nothing can really 'go bad' with the rack damper bolt. It had minimal to no effect on power output -- assuming it's still there. (No idea what happens if you try to run a motor with it removed.)

People had also thrown out (a) did someone put gas in the tank by accident and (b) have you tried running it with the fuel filler cap off? I didn't see a response to those suggestions.

__________________


Mac
2002 e320 4matic estate│1985 300d│1980 300td
Previous: 1979 & 1982 & 1983 300sd │ 1982 240d

“Let's take a drive into the middle of nowhere with a packet of Marlboro lights and talk about our lives.” ― Joseph Heller, Catch-22

will try filler cap suggestion shortly ... I am the only one to fill this car .. And it did not get a tank full of gas.
thanks for all the help folks ..

Ah well, we need to cover all the bases. It really bugs me to have to even suggest to someone that their IP is faulty.

At least 90 percent of the time problems like this aren't the pump.

__________________


Mac
2002 e320 4matic estate│1985 300d│1980 300td
Previous: 1979 & 1982 & 1983 300sd │ 1982 240d

“Let's take a drive into the middle of nowhere with a packet of Marlboro lights and talk about our lives.” ― Joseph Heller, Catch-22

did the cap off test .. No change.
another thought ... So with throttle full, I get perfect idle .. No shaking, not rough, etc
as soon as I let off the throttle just a bit, it shutters to a stop .. Is there an internal pin in the IP that is designed to sheer under certain circumstances? .. Very strange

Did you poke around and move linkages by hand while keeping the engine running? You just don't seem to hear about IP's *****ting the bed...

I hope you can get this resolved because they are nice cars indeed!

Check the air cleaner, ducts?

__________________
My occupational hazard bein'
my occupation's just not around...
1980 300SD
1980 300SD

Complete air cleaner assembly is removed at this point.. can see inlet to turbo (which is spinning freely)..
yes.. while engine is running.. can see and move linkage manually inside engine compartment ... back it off just a bit, and the engine stalls.. as if I'm pressing on the "STOP" tab at normal idle position.. really weird problem..
I mean.. it actually acts like the shaft slipped or something, and my now full is more like idle (inside IP)... but not sure if that's even possible.

Do you have access to the FSM?

(Have I asked this before?)

The rods need to be at particular lengths...

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Ok, I'm off the linkage - I figure you've covered it.

Idling fine at full throttle but dies if allowed to return to idle level throttle. You've checked the vacuum shutoff - ok. Seems to be getting good airflow thru turbo - it's spinning at least.

Fuel pump is working and hoses clear to IP.

Problem seems to be localized in the IP.

I believe there is a fuel pressure relief valve spring that can get weak and need repair. This would cause fuel starvation.

I'm thinking at low pressure and WOT, you might get just enough fuel to keep the engine running but starve it at idle position.

Have we covered this possibility yet?

__________________
Codifex
1981 240D ChinaBlue (Got her running with a donor engine.)
1983 300DTurbo w/sunroof.
1984 300TD manual sunroof. (Electrical Gremlins)

Closing off the return line from the injection pump would do it. Thats if with the line unobstructed there is fuel flowing from the return line when running. If there is no fuel flowing through the overflow line with the line open then there may not be enough operational pressure.

I would myself just put my ten dollar 0-30 liquid dampened pressure gauge into the circuit to see what the pressure is. That way if pressure is present it does not look good for the injection pump.

Good advice there.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

so let me make sure I take this right "Barry123400"
1. disconnect return line that goes back to fuel tank, and fire up.. to see if I get fuel out of the line.
2. If yes on 1, reconnect, and put inline a liquid pressure guage to measure how much pressure I have in the circuit.

at the risk of 'jumping ahead' ... gulp ... http://handbook.w116.org/Engine/617/07_1-010.pdf
but seriously though.. after reading this, I'm going to check the linkage one more time to ensure there is no shaft clamping bolt that may have failed.. hence allowing normal position of lever on shaft to be messed up.
also.. governor inside IP has moving parts, springs, etc., so odds are starting to point in that direction..

know of anyone who has opened up the IP to rebuild?

It was the clamping bolt on lever 13 that I was thinking about but I've never seen a post on here in which it loosened.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Not a user-servicable part. You don't want to go there, it requires specialized equipment.

If it comes to that -- and I hope it doesn't -- just get a used pump.

__________________


Mac
2002 e320 4matic estate│1985 300d│1980 300td
Previous: 1979 & 1982 & 1983 300sd │ 1982 240d

“Let's take a drive into the middle of nowhere with a packet of Marlboro lights and talk about our lives.” ― Joseph Heller, Catch-22