Hi, I checked old posts but I can't find anything about my problem.

My 300sd has become a real dog lately. When I take off the engine seems to stay at 2k rpm untill about 30mph. then the rpms start to increase. then it begin to accelerate pretty good. I noticed that I have to down shift to 3rd to even go slighty uphill and even then I only go 45mph. the rpms only go upto 3k. and to go above 50mph I have to have the pedal completely on the floor. I unhooked the kickdown switch because the car would surge and lose speed when it downshifted. It almost feels like somthing is holding the engine back.

Things I already did was change the filters(fuel/tranny/air), did a valve adjustment, checked boost(11psi), removed the alda, adjusted throttle linkage, cleaned fuel tank/screen, put in lower milage injectors that sprayed and popped right.

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'83 300SD with 240k
'85 300TD with 435k
'98 Ram 2500 diesel 140k

Did you do a compression check and/or see if the oil cap dances? That is probably where i would start.

I'd check the lift pump output and fuel pressure.

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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

I did the oil cap test and it dances a little bit but not alot. I haven't done a compression test on the engine yet. does anybody have a article on how to check the fuel pressure and liftpump output? I have both the chilton and haynes books. and they don't have anything on fuelpressure and output

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'83 300SD with 240k
'85 300TD with 435k
'98 Ram 2500 diesel 140k

This sounds more like a boost issue. Where did you check the pressure?

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Sam

84 300SD 350K+ miles ( Blue Belle )

I checked the boost on the port on the back intake manifold.

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'83 300SD with 240k
'85 300TD with 435k
'98 Ram 2500 diesel 140k

Advance the set screw 3/4 turn, and it'll run like a different car. That's all mine needed to run like a champ.

Try at the alda because when I had problems with this it was a combination of cracked flex fittings on the bottom of the boost overpressure valve (on the firewall) and cracked pressure lines.

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Sam

84 300SD 350K+ miles ( Blue Belle )

Not to sound rude but how would I check the boost at the alda if its not on the injection pump anymore?

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'83 300SD with 240k
'85 300TD with 435k
'98 Ram 2500 diesel 140k

Thats because all you did was hide the cause.

Skid Row Joe,
I see you too have received a spray of venom from the site Idiot. I think we need an ignore function on here.
I have always found your input to be useful and helpful, please ignore the Idiot.


INAPPROPRIATE
B.C.

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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 sure will, you've been added to my list.

Do you get a lot of black smoke when you floor it from a stop? If not you might have fuel delivery issues. Nobody kinked the fuel injector hard lines, right?

I removed my ALDA and increased boost to 13psi on my 300SD and it was a different car. Since you have already removed the ALDA you should be able to generate smoke at will

I would remove the air cleaner and the U pipe and check the turbo for tightness when you spin it by hand. It should move freely.

How is the exhaust system? Make sure you do not have any obstructions.

I smacked my center muffler with a hammer and the amount of carbon it blew out was amazing!

Also look up adjusting the Bowden cable. I set mine to shift at 3500RPM on the SD

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"I have no convictions ... I blow with the wind, and the prevailing wind happens to be from Vichy"

Current
Monika '74 450 SL
BrownHilda '79 280SL
FoxyCleopatra '99 Chevy Suburban
Scarlett 2014 Jeep Cherokee
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Gone
'74 Jeep CJ5
'97 Jeep ZJ Laredo
Rudolf ‘86 300SDL
Bruno '81 300SD
Fritzi '84 BMW
'92 Subaru
'96 Impala SS
'71 Buick GS conv
'67 GTO conv
'63 Corvair conv
'57 Nomad

* Re-install the ALDA.
* Check and adjust the injection pump linkage to the full throw stop, with a helper holding the pedal on the floor.
* Re-check the valve adjustment.
* Rebuild the lift pump.
* Install the new style primer pump.
* Replace the O-rings on the fuel filter bolt.
* Stretch the injection bypass valve spring to a rest length of 27 MM.
* Jack the car up, and check for dragging brake calipers.

Post a video of the engine (hood open); idle, quick hard acceleration, steady 2000 RPM.

you checked the tranny oil level yet?