i have an 84 300 cd-t. it has 304k and has been maintained over the years. it doesnt burn oil and seems to have all the power it should. however it rarely runs smooth at idle. the motor mounts are bad but it seems to lose a cylinder at idle. i have had trouble finding the problem. can anyone help?

Have you tried cracking the injector lines 1 by 1 and see if the problem disapears? Also, what color rack dampener do you have? Gold or silver?

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

99 W210 E300 Turbo Diesel, chipped, DPF/Converter Delete. Still needs EGR Delete, 232K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Gone and still missed...1982 w123 300D, 1991 w124 300D

i'm new at the diesel game. what is a "rack dampener"? what do u mean by "crack" the lines

Search on rack dampener. It does what it sounds like it does and causes poor idling when in need of replacement. Also search on 'diesel purge' and perform the procedure. It can help get rid of poor idling also.

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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

"Crack the line" means loosen the nut that secures the line to the top of the injector, letting the fuel leak out instead of going to the injector. You might place a rag under there to catch the fuel. Do them one at a time, and retighten after observing the effect. If loosening the line doesn't make any difference in the idle, you know that injector wasn't doing anything. If it makes the idle worse, you know that injector was working. In a spark-ignition (gasoline) engine, you would disconnect the sparkplug wires one at a time. Steve

Here is the Rack Damper Pin from two suppliers.


Item Number: 0000742674
Main Category: MERCEDES BENZ
Sub Category: Diesel Injection
Description: diesel injection pump "Rack Damper" adjustment bolt...Rear of Injection Pump



PART NUMBER SEARCH RESULTS WITH PRICES
D2030-17407 Governor Idler Adj. Pin Bosch IN STOCK



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1985 300SD
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u guys r awesome. i'm a mechanic but no nothing about german diesels. its good 2 b in touch w/ people who know what they're talkin bout thanks a lot

is their a way 2 adjust the rack damper to make it idle better or is it either good or bad?

Most people will recommend replacing the screw, as the spring may have worn out. You can try loosening the lock nut and turning the screw in to see if that helps.

Also make sure you have the motor mount shocks. Mine came without and I am looking forward to getting some!

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NC Benz
Fuquay-Varina, NC
1979 300D
1983 300D Turbo 260,000 Miles
1984 300D Turbo 345,000 Miles (sons car)
OBK #31
1998 Ford Expedition 5.4l (fer Haulin'!) 145,000
1973 19' SeaRay with 115 Mercury TOWER OF POWER!
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Ex toys:
1967 Mustang 289 (First Car)
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1975 Honda CVCC
1980 Audi 5000 Turbo

thanx 4 the tip nc benz