New member checking in - found a nice 300SD, photos inside

[Ilike300sd]

Hello!

Just bought a 79' 300SD and love this car.  The only wear on the car is some wear on top of the armrest.  Everything else is in like new condition.  Car has had zero restoration. 

I wonder if you guys can help me with the idle.  It idles very low and "clunky".  I turned the idle knob on the dash but it doesn't do anything.  How do I adjust the idle/ and/or reattach the idle knob (if that's the problem)?

Also any maintenance tips would be appreciated.  I'm planning to do the diesel purge for sure.  This car has always been maintained by MB diesel specialty shops since new so it's in a great state of repair but I'm planning on keeping this car forever so looking for any tips on recommended maintenance for ultra-long life.  I am planning on replacing the ATF with redline.  Do I need to change an auto tranny filter for this transmission?  Will flush coolant and brake fluid also.

Some pics of the car below for fun.  I have never seen a used car this nice and it's in better condition than my 08' car which I bought new.  Even those thin aluminum strips beneath the windows look new.  Some people really take care of their cars.

[Casey]

Nice!  Same interior and exterior color as my 1980 300SD!  Looks like you've also got a sunroof?  But I don't see a passenger side mirror...  May I ask how  much you paid, and how many miles you've got on her?  Looks like you've got a crack-free dash, which is rare.  I'm guessing this has been garage kept most of it's life?

There's a bunch of recommended things to do at around 200k miles, but I'll wait to hear what you're mileage is before bothering with that.

Diesel purge works great, but make sure you've got new fuel filters to put on, and you'll want to use a full two cans the first time.  I'd recommend upgrading to Monark fuel injector nozzles - you get a lot more power from this alone.  Check out http://www.youtube.com/watch?v=XtN-g9onjwk to see me test driving after installing them.  Cost is just a little over $100 from MercedesSource.com - you'll want new crush washers that go underneath of the injectors too, and an appropriate sized socket and torque wrench if you haven't got them already.  The site has those as well as an injector testing kit and adjustment shim washers, but you likely don't need all that.

How bad off is your armrest?  Do you just need a new skin or is the interior foam damaged as well?  There's a good one at my local junkyard but the skin is bamboo color, not tobacco.

I'm curious about the idle adjustment myself.  The 1980 got rid of the knob and made it automatic somehow, but my 1982 300CD has a broken adjustment knob.

Yes, there is a filter in the transmission.  To check the fluid level, drive it around for a bit to get it to operating temperature, then park it somewhere level, and check it while the engine is running.  MB recommends using a piece of leather to wipe the stick to avoid any particles getting into the tranny.

You probably want to park it in a garage or on top of a sheet or something where any leaks will be obvious, then try to figure out where they are coming from - you can expect some rubber parts to be worn out.  Also if the engine compartment isn't clean there may be leaks from a broken gasket or hose in there.  While you're at it test your fuel primer pump out and see if it leaks when you use it - those readily go bad too (MercedesSource has an awesome all-metal replacement).  Check the tie rods and if the shifter feels loose, you need the bushings replaced (doesn't cost much).  The vacuum lines use rubber couplings and these tend to get brittle and loose with time - that will manifest in problems with the automatic door locks, climate control, etc.

Also take a lesson from me - take your doors apart and lubricate your window regulators.  All four of my windows worked when I bought the car, but the front two broke within a couple weeks.  You likely also may have broken door check straps (which keep the door held open either half way or all the way).

Lovely car!  If you end up "upgrading" to euro headlights, bumpers, or replacing anything else, let us know as you'll find interested parties on this forum, myself included!  And if you need to purchase any new OEM parts, check with jbrasile on this forum!

[Squiggle Dog]

Excellent car, amazing condition! It's great to have another 300SD owner here. Only a little more than a year ago it seemed that I was the only 300SD owner on the forum, now this year we have many! 2011 is the year of the 300SD on the forum.

[Ilike300sd]

Nice!  Same interior and exterior color as my 1980 300SD! how many miles you've got on her?  Looks like you've got a crack-free dash, which is rare.  I'm guessing this has been garage kept most of it's life?

Mileage is 255k, yes garaged all it's life

How bad off is your armrest?  Do you just need a new skin or is the interior foam damaged as well?  There's a good one at my local junkyard but the skin is bamboo color, not tobacco.

It's not too bad, probably just have to live with it.  It just sticks out because it 's the only real flaw,  You can see it in this photo:

I'm curious about the idle adjustment myself.  The 1980 got rid of the knob and made it automatic somehow, but my 1982 300CD has a broken adjustment knob.

I ended up turning the cable adjustment counterclockwise many, many turns.  The cable is a pretty straight shot from the dash to the "cable holder" near the intake so was pretty easy to spot.  Now I can idle at about 900ish on the max side and pretty low on the low side (didn't check rpms for low idle).  So I'm happy with it as far as idle speed now.  I'm just thinking the idle should be smoother overall though.  Maybe the valves need to be adjusted?  Maybe the diesel purge will make a difference also.  Also one thing I noticed is that the throttle pedal should always be pushed down when turning the idle adjustment knob counterclockwise.  That way there is zero "load" on the cable and the cable doesn't really have to do any work.  I think if a guy used the cable to pull the throttle it would wear out earlier.  Even though it's a small amount of pull distance wise, it's a fairly heavy load for that little cable to pull.

I downloaded all the W123 factory manuals (can't find W116) and there are quite a few pages on the throttlle linkages etc.  Let me know if you want me to post those here.  I assume they are already in some library or something on this forum?

Yes, there is a filter in the transmission....

I'll have to change the filter then when changing the ATF.  I'm always afraid that if I take a car to the shop for tranny service they will cheat and just leave the old filter in.  I hate doing it but will prob. do myself due to that concern.

any leaks will be obvious...you can expect some rubber parts to be worn out.  ---Also if the engine compartment isn't clean there may be leaks from a broken gasket or hose in there.  While you're at it test your fuel primer pump out and see if it leaks when you use it - those readily go bad too (MercedesSource has an awesome all-metal replacement).  Check the tie rods and if the shifter feels loose, you need the bushings replaced (doesn't cost much).  The vacuum lines use rubber couplings and these tend to get brittle and loose with time - that will manifest in problems with the automatic door locks, climate control, etc.---

No leaks so far knock on wood : )  You are right about the rubber parts.  I noticed the tube from the air cleaner to the turbo was loose and it turned out that the dense rubber "gasket/collar" where the turbo meets the hose was cracked.  That baby must get hot right there. have to find another one of those gaskets somewhere.  It's not an acceptable fit for that hose with it cracked.  Doens't feel like it is tight and solid.  The rest of the items above appear to be good on quick examination but great things to watch for and I will have to check them more closely when I realy dig into the maintenance stuff.

Also take a lesson from me - take your doors apart and lubricate your window regulators.  All four of my windows worked when I bought the car, but the front two broke within a couple weeks.  You likely also may have broken door check straps (which keep the door held open either half way or all the way).

Excellent idea!

Lovely car!  If you end up "upgrading" to euro headlights, bumpers, or replacing anything else, let us know as you'll find interested parties on this forum, myself included!  And if you need to purchase any new OEM parts, check with jbrasile on this forum!

Great, Thanks!

[Ilike300sd]

@Squiggle Dog, This SD  feels like you are gliding along on a huge bed of soap bubbles and you only know the road is somewhere underneath you because you can see the yellow stripes going by.  How in the heck did they do that?  And whats more, how does it still feel like that after 30 years of use?  Amazing.  The build quality is really unreal.

[Casey]

Mileage is 255k, yes garaged all it's life

Nice, mine's around 200k.  In that case, you'll want to look into replacing the valve seals, timing chain, rebuilding the turbocharger, etc. if those haven't been done already.  You want to do a valve adjustment for sure - that should be done every 12k miles.  MercedesSource has a nice set of custom wrenches for the job that make it a lot easier and a really nice feeler gauge set.

It's not too bad, probably just have to live with it.  It just sticks out because it 's the only real flaw,  You can see it in this photo:

Is that leather?!?  My interior is MB-Tex, but I'd love to convert to leather at some point.  You can get new replacement leather for any of the interior from GAHH.

I downloaded all the W123 factory manuals (can't find W116) and there are quite a few pages on the throttlle linkages etc.  Let me know if you want me to post those here.  I assume they are already in some library or something on this forum?

http://handbook.w116.org

No leaks so far knock on wood : )  You are right about the rubber parts.  I noticed the tube from the air cleaner to the turbo was loose and it turned out that the dense rubber "gasket/collar" where the turbo meets the hose was cracked.  That baby must get hot right there. have to find another one of those gaskets somewhere.

New OEM parts are pretty readily available most of the time, and jbrasile can hook you up with good deals versus list.

[1980sdga]

Stunning car  I have 2 1980's though neither are as nice as yours. 

I think the  manual "fast idle" is a plus and I believe most 79's had non-egr engines. It would be interesting to know which you have.

I have been driving mine sometimes 1000 miles a week for several months. Great road cars. Easy on fuel and it's a REAL CAR. Both of mine improved quite a bit after several tanks of fuel with diesel additive and filter changes. Warm it up and run it out. I'm amazed at how well my doors close after 30 years 

I'd check out the brakes, wipers, tires, lights etc. Sounds like your tachometer works  (That's a plus) They normally have some niggles like vacuum lock issues or climate control problems but they are really rewarding cars to operate once sorted. 

Congrats on an awesome car!

[jbrasile]

Ilike300SD,

Wow, what a great car!!! Congratulations.

All suggestions are spot on but hold off on valve seal replacement or turbo charger rebuild unless you detect some anomaly. My sister's 84 300SD has 320k miles and has never had this done and it sill performs like it did when we bought it way back in 1992 with 68000 miles. If the car was properly maintained, which certainly looks like it was, you should not have any problems. I usually prefer to keep the engine factory original for as long as possible.

As for your idle issue, these cars rarely need adjustment but if yours is too low first make sure the manual adjustment is set all the way down. The idle adjustment screw is located towards the rear of the injection pump, it is actually a screw that is held in position by a 14mm nut. Get a deep 14mm socket and put it over the screw so you can loosen the nut. Once that is done, just turn the screw clockwise until you get to the correct idle speed which should be 850-900 rpm. Re-tighten the nut making sure the idle doesn't change. You may have to fiddle with the screw a little to compensate for any movement while tightening the nut.

Adjusting the valves will have amazing results in these cars, idle will be remarkably improved and so will fuel economy and performance.

Check also if your manual rpm control is working properly, I don't remember what the correct RPM is when you turn it all the way clockwise but it should be around 1500rpm.

Looks like you have a leather interior, a new arm rest cover is available from GAHH, we can supply at $119.85 (141.00 list)in the correct color and grain.

I have also noticed that the little aluminum trim piece around the rear portion of the left rear door arm rest is missing, let me know if you would like a quote on that.

How is your a/c and power locks? These tend to give a little bit of a headache bu the car looks so original that diagnostics and repairs should be pretty straight forward.


Tks,

Joe

[pompy]

Congrats on a fine car. I luuuvvv the colour combo.
116 is beautiful.

[Casey]

All suggestions are spot on but hold off on valve seal replacement or turbo charger rebuild unless you detect some anomaly.

Why's this Joe?  I thought the valve seals were best done proactively before they caused bigger problems, and that the turbos generally wear out and work less ideally after 200k+ miles.

I haven't done my 300SD yet as I used the valve seals I got on the CD (waste of time/money sadly), but was planning on ordering another set from you and already have the turbo rebuild kit.  If there's good reason why I should hold off on these, I'd really like to know what it is, in which case I very may will!

[1980sdga]

Joe will chime in but my 2 cents from years of gasser wrenching 

Valve stem seals- Unless it's smoking blue when you first start it up after cooling down a bit I wouldn't worry about it. The oil in the head can dribble down the valve stem and get in the combustion chamber which smokes when you fire it up.  It can foul spark plugs. Wait, NO PLUGS  Sometimes worn valve guides can lead to leaky valve seals so replacement doesn't always fix the problem for long.

Turbo- I've had turbo gassers for years. They are VERY DURABLE little buggers. As long as the center bearing is OK and the turbines aren't hitting the housing and the blades are in good shape I wouldn't sweat it. Just keep the oil changed. I have always let my turbos cool down after driving under boost for any amount of time. I just let it idle for a few minutes before shut down to let the turbo and bearing cool. Lotta folks say you don't have to do this with modern oils but old habits are hard to break...

[Ilike300sd]

@Raptelan, I second what 1980 sdga said re turbos.  FWIW I've had saab (gas) turbo's run past 300k with no issues.  For those early saab turbos the key to longevity was using an oil that can withstand the heat and letting it idle a bit before shutting off.  I don't know if the MB diesels use the same turbo as saab gas or not but my first saab turbo was 1978 so it is about the same time period.  I think 1978-79 maybe the first appearance of turbos (in mass production I mean)? Those turbos could go at least 300k (and probably much longer I just never owned one wih really high miles, say 500k) if good oil was used.  I always used, and still use, ester-based oils with high amounts of additives.  These oils cost more because esters are much, much, more expensive than group III or PAOs but they are worth it IMO.

Also thanks very much for the link to the manual!  I used it to find the idle screw mentioned above and plan to adjust that today.

[Casey]

@Raptelan, I second what 1980 sdga said re turbos.  FWIW I've had saab (gas) turbo's run past 300k with no issues.  For those early saab turbos the key to longevity was using an oil that can withstand the heat and letting it idle a bit before shutting off.  I don't know if the MB diesels use the same turbo as saab gas or not but my first saab turbo was 1978 so it is about the same time period.  I think 1978-79 maybe the first appearance of turbos (in mass production I mean)? Those turbos could go at least 300k (and probably much longer I just never owned one wih really high miles, say 500k) if good oil was used.  I always used, and still use, ester-based oils with high amounts of additives.  These oils cost more because esters are much, much, more expensive than group III or PAOs but they are worth it IMO.

Also thanks very much for the link to the manual!  I used it to find the idle screw mentioned above and plan to adjust that today.

I started a thread on oils (am thinking of going with Amsoil) over here - are any of those ester oils?  I'm not sure of what the terminology means...:
http://forum.w116.org/mechanicals/amsoil-which-is-best/

So it might be a little overkill to rebuild the turbo, but it shouldn't hurt.  It's basically just swapping out the turbine piece that goes inside, and all the seals.  Maybe I'll just hold onto the kit for later...

Does anybody know what the idle should be set to for a 1980 which doesn't have the manual adjustment?  I think mine may need adjustment - the engine shakes a lot at idle (getting the whole car moving) unless I give it a tiny bit of fuel.  I still need to get the new engine shocks installed, and should do a valve adjustment, but I'm thinking my idle might be a bit low.

[Casey]

I think the  manual "fast idle" is a plus and I believe most 79's had non-egr engines. It would be interesting to know which you have.

Do you know if our 1980's have an automatic adjustment of some sort, or did they just drop the feature?  If the latter, I wouldn't mind re-adding it to mine...

[1980sdga]

I think the  manual "fast idle" is a plus and I believe most 79's had non-egr engines. It would be interesting to know which you have.

Do you know if our 1980's have an automatic adjustment of some sort, or did they just drop the feature?  If the latter, I wouldn't mind re-adding it to mine...

I've never noticed much idle change from cold but both of mine are a little cold natured. I think the manual idle would be great.

Are you going to be daily driving it Ilike 300sd? Also, where are you located?