I edited post #1. to include the most common MB diesel bypass valves, and their engine application.

If you are in doubt, call with your VIN#, year, make, and model.

__________________
ASE Master Mechanic
https://whunter.carrd.co/

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
2003 Volvo V70

https://www.boldegoist.com/

I think this is true because I once read in a factory manual for this series of IP that they could be GRAVITY fed without a lift pump.

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Ron Schroeder
'85 300 Turbo Diesel 2 tank WVO
'83 300 Turbo Diesel 2 tank WVO
Some former WVO vehicles since ~1980:
'83 Mercedes 240D
'80 Audi 4000D
'83 ISUZU Pup
'70 SAAB 99 with Kubota diesel
'76 Honda Civic with Kubota diesel
'86 Golf
Several diesel generators
All with 2 tank WVO conversion
LI NY

Both springs are in my hand.

I am looking for a local spring supplier at this moment.
Hopefully a company that will not fold in a few months..

Might be good to get a tech spec of the spring. That way any spring supplier could provide one.

__________________
Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

I'm looking to source that part in Canada for my 1992 300D 2,5 Turbo.

It has all the symptoms of fuel starvation while having good flow and pressure from the charging pump. Not measured, but I removed all 5 injectors recently and reprimed them all quickly and easy by just cracking one injector open...

As for the symptoms themselves: the car has a sudden loss of power at about 2800rpm. (Bear in mind I have converted the car to a pressure type wastegate as described by GSXR).

Because I thought it was the wastegate openning all the time, I intentionnally blocked the wastegate pressure actuator feed line so it would not open anymore (knowing to be carefull not to overboost).

Now I got pressure surges to 18-19psi at 3000rpm BUT yet no power! Then I came back here because I suspected fuel starvation. Checked everything from fuel tank to fuel filter (which is quite recent). Fueled to the same gas station as always, no problem there.

And here I find about that fuel checkvalve.

I'll post my results for sure when I'm done with that checkvalve.

Thanks,

__________________
BigBen

'98 E300 Turbodiesel 244 000km
RIP '92 300D 2,5 Turbo 632 859,4km due to engine failure

Mercedes part # 601 070 01 46
Bosch part #1 469 990 351

Friendly,not so Local, Bosch Diesel Service Center Says:
Valve OBSOLETED by Robert Bosch Gmbh August 2002

Suggestion from him: ("If it were Mine")
VE type Pumps have the same Fuel Pressure AND their
overflow valve(s) are simply a Orifice (Venturi) WITH
a Teenie ,Tiny screen filter...

Bosch part# 1 463 456 303

So, the only draw back to substituting the VE overflow
for the M type would be NO Bio"D" above 20% AND
Certainly No WVO. (Trash in the fuel would clog the
tiny screen.)

On the positive side the VE type Overflow Valve is
only $15.00 USD (When ordered as Bosch part# from Bosch)

__________________
'84 300SD sold
124.128

Bosch dropped them because MB contracted another company to make them cheaper.


They are availible here.
Post# 1.



Diesel fuel return valve/banjo bolt, back of injection pump by engine block, at nylon return line going to fuel filter housing.
MB# 6010700146


Application list:

OM601. 911, 912, 921, 940, 941

OM602. 911, 912, 930, 931, 938, 939, 940, 941, 942, 946, 947, 948, 961, 962, 990, 991, 993

OM603. 912, 913, 931, 960, 961, 962, 963, 970, 971, 972

OM616.963

OM661.911

OM662.911

NOTE:
You should replace the banjo bolt/valve seal rings at this time.

Two of the following
Seal ring
MB# 007603012405


.

"Bosch dropped them because MB contracted another company to make them cheaper."

I'm beginning to get this Pre-deja Vu feeling that A Lot of MB parts will end up in that same "Bin".

Ya Know,Ladies and Gents, it might behoove us to acquire at least one of each
part "You really can't do without"...
I'm beginning to see a 10 year Pattern (After 10 years DB "Drops" the parts)
almost as if Mercedes were a US company...
Let us not forget,anybody only "Has" to supply parts in the US for "Only" Ten Years after model cessation...
AND unfortunately DB has taken that "Cheap" way out...

A once Proud,Meticulous engineering company that led the world in innovation
and customer service has been degraded to "Untermenschen",by Bean counters.

__________________
'84 300SD sold
124.128

Say it isnt so! Out of all the old cars I have this has been the easiest to find parts for . look down at my signature if you dont beleive me.

AMC

Hunter did you ever find a spring supplier that can identify or come close to the old type spring ? Theres a spring place in san antonio I was going to check with but work and life keep getting in the way. Its ace spring on brooklyn st if anyone around here has time and can get there before me. They have a whole wall full of springs. They specialize in auto leaf springs . Go figure.

__________________


Experience : what you receive 3 seconds after you really needed it !!



86 300SDL 387,000? Motor committed suicide
81 300SD 214,000 "new" 132,000 motor
83 300SD 212,000 parts car
83 300SD 147,000

91 F700 5.9 cummins 5spd eaton 298,000
66 AMC rambler American 2dr auto 108,000
95 Chevy 3/4 ton auto 160,000
03 Toyota 4runner 180,000 wifes

I didn't know about this. Thanks for sharing, oh Great Hunter!

I suspect I might have this issue with my 240D. It seems a bit lethargic on these mountains, and the exhaust is never very sooty. Floored in 2nd gear going up these hills around here it should be leaving a cloud of black soot, but it doesn't. Needs more soot.....discourages tailgaters!!

__________________
1979 240D, 4spd manual, Power Sunroof, manual windows, 147k miles, Pastel gray/Black MB Tex.
1991 300D 2.5 - Smokes like it's on Crack!

I was told today at a Bosch Shop that the Bosch part number mentionned before did not exist! They have asked me to provide the pump nameplate details to help.

MD dealer told me they can get the part, but they have to order it from Germany, will take 10 days to get and costs 84,60$ (Canadian).




But Peachparts will not ship to Canada, right? At least that's what I recall from last time when I needed the vacuum pump.

Thanks,

__________________
BigBen

'98 E300 Turbodiesel 244 000km
RIP '92 300D 2,5 Turbo 632 859,4km due to engine failure

Shipping to canada
Shipping to canada

Well, it seems I should have measured pressure because I installed the new overflow valve and no help.

In fact it did improve a bit, but when I really need power like under acceleration in motorway access ramp, the car stalls...

Primer pump will be rebuilt this week. Will report on the results.

Bye,

__________________
BigBen

'98 E300 Turbodiesel 244 000km
RIP '92 300D 2,5 Turbo 632 859,4km due to engine failure

So I got everything put back together. I have had the pump rebuilt for 140$ and the overflow valve purchased for 20$, all from a very helpful Bosch Service center in Qc City.

It did restore performance and car now works perfectly. I therefore had a combination of 2 problems related to overflow valve and primer pump (which I initially thought it was all right).

But I must also say, to be honnest, that I had an issue related with my WVO system. I had not initially plug the return banjo bolt in the fuel filter housing...

I'll discuss that a little later in the proper section.

Many thanks,

__________________
BigBen

'98 E300 Turbodiesel 244 000km
RIP '92 300D 2,5 Turbo 632 859,4km due to engine failure