slow acceleration 87 300sdl

Hi Everyone. I had an '85 300sd a couple of years back that had the same problem.. slow acceleration. After the rpm's build up, there is plenty of power & acceleration, just not at takeoff. I think TG
Lambach gave me the tip, but after much searching through the archives i still haven't found it. It seems like it was something to do with the diesel injection timing or linkage, but i can't find it on the mb cd either. So if anyone out there knows, please refresh my memory.
I got this car about a week ago.. my '85 SD died a couple of years back from overheating & I've been missing the nice ride of the 126. I like the style & pep of the sdl 6cyl.. i guess they have been pretty good engines. This is a one- owner with 160k on it. The trap oxydizer has been removed & it seems to have been well taken care of. The only other thing is the cruise control doesn't work. Perhaps in another post we might delve into that!
I've done a lot of wrenching, so are there any suggestions as to any preventative maintenaince for this baby? I plan to keep it for a *long* time, & i won't mind putting in a little ounce of prevention. Should the timing chain be checked/replaced? injectors? I got a compression testor when the '85 played out, so i guess i can check the compression.
I have also noticed it seems to be running a little hot. I'm in AZ, so it gets very hot here. I read somewhere that the radiators get clogged easily in these models. Can they be flushed, or would a replacement be better?
Thanks again for the replies. I'm sure i will be visiting here often from now on!
Scott Wilcox Sedona, Az USA
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If your old '85 300SD died from overheating the prospects for this car are NOT good. It's hard to kill the old cast iron 5s and quite EASY to kill the straight sixes. No kidding.
The aluminum head on this straight six is prone to cracking - when overheated. So the "soft" spot of these cars is their cooling system. If
you're to have a good ownership experience with this six you MUST take excellent, not good, but excellent, care of its cooling system, especially since you're driving it in a very hot area.
What's excellent maintenance? Flush the system and be sure the radiator is clean inside and out. If there's any doubt, buy a rebuilt radiator (see: www.resedaradiator.com). Renew the coolant every two years and be sure the proportion of coolant to water are correct. Finally, when you drive you need to take into account the car's weakness so when scaling a
long hill turn off the A/C AND moderate your speed - don't charge up the
hill - for the most BTUs the cooling system must shed are upon hard acceleration, which is usually brief, and long hill climbing, which is not brief.
The symptoms of head gasket failure and / or a cracked head are: overheating, oil in the coolant, coolant in the oil, white smoke upon start up. That's so you'll know when it happens, then pray it's only the
head gasket.
As to experts on this engine, see: www.mbz.org and join their free Diesel list, many of those participants own or have owned this engine and can help you with its technicalities.
Finally, to your initial question. Why is it a slug upon start off but has lots of power as the speed builds.
As to a baseline, you should know that this car's 0 to 60 performance is
about 13 seconds so have reasonable expectations as to its acceleration.
Accelerator linkage is the first thing to check. Have an assistant inside the car operate the accelerator while you observe the linkage, particularly at the injection pump (engine OFF). When the accelerator is
floored the linkage at the IP should come to rest against the full throttle stop screw. If it doesn't adjust the linkage so it does. This is a bit complicated; keep a written record of any adjustments made so you can restore the original setting if necessary. If nothing found to be amiss with the linkage you need some expert help from the Diesel group, there are some vacuum controls to the turbo etc. that may not be operating correctly and that's beyond my knowledge.
Tom
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If your old '85 300SD died from overheating the prospects for this car are NOT good. It's hard to kill the old cast iron 5s and quite EASY to kill the straight sixes. No kidding.
The aluminum head on this straight six is prone to cracking - when overheated. So the "soft" spot of these cars is their cooling system. If
you're to have a good ownership experience with this six you MUST take excellent, not good, but excellent, care of its cooling system, especially since you're driving it in a very hot area.
What's excellent maintenance? Flush the system and be sure the radiator is clean inside and out. If there's any doubt, buy a rebuilt radiator (see: www.resedaradiator.com). Renew the coolant every two years and be sure the proportion of coolant to water are correct. Finally, when you drive you need to take into account the car's weakness so when scaling a
long hill turn off the A/C AND moderate your speed - don't charge up the
hill - for the most BTUs the cooling system must shed are upon hard acceleration, which is usually brief, and long hill climbing, which is not brief.
The symptoms of head gasket failure and / or a cracked head are: overheating, oil in the coolant, coolant in the oil, white smoke upon start up. That's so you'll know when it happens, then pray it's only the
head gasket.
As to experts on this engine, see: www.mbz.org and join their free Diesel list, many of those participants own or have owned this engine and can help you with its technicalities.
Finally, to your initial question. Why is it a slug upon start off but has lots of power as the speed builds.
As to a baseline, you should know that this car's 0 to 60 performance is
about 13 seconds so have reasonable expectations as to its acceleration.
Accelerator linkage is the first thing to check. Have an assistant inside the car operate the accelerator while you observe the linkage, particularly at the injection pump (engine OFF). When the accelerator is
floored the linkage at the IP should come to rest against the full throttle stop screw. If it doesn't adjust the linkage so it does. This is a bit complicated; keep a written record of any adjustments made so you can restore the original setting if necessary. If nothing found to be amiss with the linkage you need some expert help from the Diesel group, there are some vacuum controls to the turbo etc. that may not be operating correctly and that's beyond my knowledge.
Tom
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Sorry for the duplications the news server didn't respond to the messages so I sent 'em again!
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Follow Dave M.'s tips to adjust the ALDA unit... he says this is the big thing for off-the-line speed on those OM603's! I have yet to adjust mine, but it seems simple and straightforeward:
- Mike
--
Hi all,

Well, I finally finished twiddling with the ALDA on my blue car (you know,
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