I'm looking at getting an old W126, OM617 powered 300SD. I was thinking Rotella T 5w40 would be pretty ideal, but what kind of interval could I safely run that $40+(~8 quart sump) worth of oil at? It would be my DD, so -20*f to 90*f Michigan weather would be seen, which rules out 15w40.
Oil and OCI for a MB 300SD
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If most of your trips are more than 10-15 miles highway then you can safely do 8-10k miles between oil changes.
I've owned a vehicle with that engine (OM617.95x). Owner's manual specifies 5K change intervals with severe service changing at 2.5K miles.
Extending change intervals risks more rapid wear on the timing chain; you really don't want that to skip teeth or break (new camshaft, among other parts).
That engine needs a valve adjustment every 15K miles. Clearances may be off either direction on any given valve; an intake valve with too tight a clearance will make it very difficult to start in cold weather. Below 0F you'll need a block heater if you expect to get it started.
Extending change intervals risks more rapid wear on the timing chain; you really don't want that to skip teeth or break (new camshaft, among other parts).
That engine needs a valve adjustment every 15K miles. Clearances may be off either direction on any given valve; an intake valve with too tight a clearance will make it very difficult to start in cold weather. Below 0F you'll need a block heater if you expect to get it started.
JHZR2
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I have owned and do currently own 617.952 engines. RT 5w-40 is a great choice. Id run UOA, but 6-7000 is more than doable based upon soot loading. Beyond that youll be over 1% soot loading and then youll have potential for higher "stretch" (wear) on the chain.
Have you disabled EGR?
Have you disabled EGR?
I would not be worried about running RT6 in any non-race car/engine to 7500K miles.
On the question of valve adjustments, I alwasys wondered whether they are even necessary. I have never done valve adjustments in any of my rides, and have never had any problems, but that's not to say that, what I've done is the right thing to do, or that anyone should follow it... I was just stating what I've done, and what's worked for me in my 240D.
On the question of valve adjustments, I alwasys wondered whether they are even necessary. I have never done valve adjustments in any of my rides, and have never had any problems, but that's not to say that, what I've done is the right thing to do, or that anyone should follow it... I was just stating what I've done, and what's worked for me in my 240D.
JHZR2
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Youve never adjusted the valves on your 240D? They are likely tight then.
7500 on the basis of TBN, oxidation and soot loading is doable. on an IDI older design like the 617, 6000-7000 is better to keep it below 1%. The oils are designed to safely disperse 2-4% soot without impacting wear.
7500 on the basis of TBN, oxidation and soot loading is doable. on an IDI older design like the 617, 6000-7000 is better to keep it below 1%. The oils are designed to safely disperse 2-4% soot without impacting wear.
yeah that's what I've heard, that most likely the valves are real tight. what happens when they are very tight? Is that supposed to be real bad for your engine? The engine sounds great, has great compression, starts rigth up in less than 2 seconds in cold/freezing weather, so I figured why mess with a good thing.
Only tune-up I've ever done on the engine aside from changing the fuel filters every 15 to 20K, is the "italian tune-up" while going up mountains, driving to seven springs, or Pittsburgh.
Only tune-up I've ever done on the engine aside from changing the fuel filters every 15 to 20K, is the "italian tune-up" while going up mountains, driving to seven springs, or Pittsburgh.
JHZR2
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The Valves get tight on our cars becuase the valve wears and beats away on its seat and actually move further into the head to actually seal after time. This "further in-ness" results in the stem stick out further which results in your valves getting "tight" and/or the valve getting held slightly open.
The issue is that the valves are kept cool by good contact with the head. If they arent set right, youll burn the valves. The main issue though is that tight valves cause compression loss which effects starting and power.
The issue is that the valves are kept cool by good contact with the head. If they arent set right, youll burn the valves. The main issue though is that tight valves cause compression loss which effects starting and power.
JHZR2
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Its a three wrench system on these cars. Pretty easy.
JHZR2
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FYI, all youve ever wanted to know about valve adjustments on OM61x engines:
http://www.peachparts.com/shopforum/diesel-discussion/107729-valve-adjustment-om615-616-617-fyi.html
http://www.peachparts.com/shopforum/diesel-discussion/107729-valve-adjustment-om615-616-617-fyi.html
Originally Posted By: default
Valve adjustment with threaded adjusters is easy, if you know what feeler gauges are, you're overqualified.
I know what those feel gauges are!!! in fact I ordered them online a few years ago, along with a valve cover gasket (as I read that it's a good idea to replace the valve cover gasket at the same time you do the valve adjustment).
I think I have all the tools i need, I just wondered if it was really a necessary maintenance item. having read what you guys wrote though, I am assuming that my valves are probably extremely tight...so I will give it a shot this weekend if the weather cooperates.
Wonder why I have not experienced any problems starting, or any sluggishness or loss in power though.
Valve adjustment with threaded adjusters is easy, if you know what feeler gauges are, you're overqualified.
I know what those feel gauges are!!! in fact I ordered them online a few years ago, along with a valve cover gasket (as I read that it's a good idea to replace the valve cover gasket at the same time you do the valve adjustment).
I think I have all the tools i need, I just wondered if it was really a necessary maintenance item. having read what you guys wrote though, I am assuming that my valves are probably extremely tight...so I will give it a shot this weekend if the weather cooperates.
Wonder why I have not experienced any problems starting, or any sluggishness or loss in power though.
JHZR2
Staff member
It is smart to replace the VC gasket.
If it hasnt been done in a while, Id do it, drive about 200-300 miles, then repeat. Often we find that they change a bit as things settle in.
If it hasnt been done in a while, Id do it, drive about 200-300 miles, then repeat. Often we find that they change a bit as things settle in.
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