What should I do... 300SD or SDL

[LUVMBDiesels]

Hey Guys,

If you read my other thread about the demise of Bruno my 300SD, you now that he died last week with a seized engine. I have not brought him to a mechanic yet so I do not know if he can be revived (If you missed that saga, He was running with good oil pressure and at 80 degrees when something went clunk and the engine stopped. I am hoping it is thechain that drives the oil pump and nothing else)

If I cannot keep Bruno on the road without dropping a new engine I will be selling him for parts.

What should I buy to replace him? I love the W126 and want to stay in that family. Should I go with another 617 engine and the simplicity it brings or should I upgrade to a 300SDL and get the 603 engine and all the advances like ABS that are built into the newer car? I am assuming that any 603 I get has had the head replaced...

What you you do in my situation?

Thanks!!

[Charles_B]

Don't assume that heads would have been replaced. I still have original on my 86, thats never been overheated as far as I know. It even still has the trap ox sorta, since it was a Calif model when bought.

[LUVMBDiesels]

I meant that any 603 I looked at would not have the #14 heads.

If I look at a car with the original head, how can I tell if it has overheated? Will they all crack and put oil into the coolant?

I am not familiar with any MB diesel except the 617.95x turbo diesels

[Bill Ladd]

PM sent. I love my SD and my SDLs for different reasons. The SD is much simpler overall and mine runs like a scalded cat now that I have a new tranny installed and all the pressures and vacuum worked out.

That 603 motor seems to be more finicky, but is much smoother, much more quiet and more powerful when in proper tune.

I've read here more than a few times about the additional length of the SDL and city driving/parking, but never have had an issue with it.


I reckon, assuming you get a good example, you can't go wrong either way.

[LUVMBDiesels]

Originally Posted by Lux

PM sent. I love my SD and my SDLs for different reasons. The SD is much simpler overall and mine runs like a scalded cat now that I have a new tranny installed and all the pressures and vacuum worked out.

That 603 motor seems to be more finicky, but is much smoother, much more quiet and more powerful when in proper tune.

I've read here more than a few times about the additional length of the SDL and city driving/parking, but never have had an issue with it.


I reckon, assuming you get a good example, you can't go wrong either way.

Having parked a Suburban in NYC I am not afraid of the length of the SDL. I love my SD and would drop another engine in it but that would make three (original was going bad when I bought the car) and the body would still have rust issues.

How do you find the extra gadgets on the SDL? Do they work or do they take away from the tank-like reliability of a Benz?

What kind of mileage do you get on a 603? I have heard they they get better mileage than the 617 even with the extra weight of the car.

[Hatterasguy]

They are both excellent cars, the 300SD is by far the better around town car.

So what if it has a 14 head? Most of the 603's out their probably have the original head. Don't do something stupid like neglect the cooling system and overheat it.

I don't know what "gadgets" you are refering to they are pretty much the same car...oh wait the SDL has tilt on the sunroof and memory seats...not what I would call a complex car. These days the W126 is about as complicated as your average garden tractor.

[Bill Ladd]

Originally Posted by LUVMBDiesels

...the body would still have rust issues.

That's a deal-breaker for me, right there.

Originally Posted by LUVMBDiesels

How do you find the extra gadgets on the SDL? Do they work or do they take away from the tank-like reliability of a Benz?

'Bout the same between the cars

Originally Posted by LUVMBDiesels

What kind of mileage do you get on a 603? I have heard they they get better mileage than the 617 even with the extra weight of the car.

Never really worry too much about mileage. Fill 'em up with dino, b-20, b-50 or b-100 whenever they need. Although it feels like the 603s are less thirsty.

[Bill Ladd]

Originally Posted by LUVMBDiesels

Will they all crack and put oil into the coolant?

No. My '86 has 300,000 plus miles with no cracks/coolant loss.

[sixto]

You should drive every SD and SDL for sale in your area before deciding... to get a W140

Seriously, do a side-by-side comparison. I expect it will be more a matter of the condition of what's available when you need a car rather than simply the difference between an SD and SDL.

Sixto
87 300D

[Hatterasguy]

Originally Posted by sixto

You should drive every SD and SDL for sale in your area before deciding... to get a W140

Seriously, do a side-by-side comparison. I expect it will be more a matter of the condition of what's available when you need a car rather than simply the difference between an SD and SDL.

Sixto
87 300D

X2, just buy a late model W140 and be done with it.

[LUVMBDiesels]

My 300SD has the usual rust onthe right 1/4 panel over the wheel arch. It also has the beginnings of rust on the drivers door where the stupid plastic cladding holds water. other than that EVERYTHING works from the AC to the tach to the sunroof. Fixed most of it myself, including dropping in what I thought was a good engine from a low mileage W123 two years ago. The original engine in the car had only 140,000, but was not maintained well and developed a rod knock. I pulled it while it was still running and it is up in NY on a stand. (I was going to tear into it but never got around to it) because of this I have a good 617 head, IP, turbo, etc.

It cost me about $900.00 to buy this engine and took a lot longer than I thought to install it. I kept getting held up by dumb things like the oil filter housing needing to be swapped.

Now the thing went screech, clunk and siezed. I had only put about 100k on it with oil changes every 4000 miles and filter changes every 2000mi. I thought that would prevent things like this from happening. I had never even heard of an oil pump chain failing or a pump shaft snapping. Of course this is speculation as I have not been able to do more than look at the outside of the engine down here in WV. It could have snapped the camshaft, crankshaft, or anything else that would not punch through the block. The engine is still full of oil and there are no visible holes wher anything punched through. I am going to bring it over to John Hef soon so he can drop the oil pan and see what is going on.

If the engine can be saved I will gladly fix it. I will be up in NY on the weekends so I can pull any parts of my old engine that John says are broken in the new one. If the engine really is toast, then I do not know what to do. Going out to look for another replacement and then PAYING somebody to do the work down here will be painful. Also, a new engine would still leave me with rust issues.

That being said, I looked at a 1986 SDL last night.

The Good:

Nice paint - no dents, bad scratches, etc
No rust!! I even pulled up the trunk liner...
Windows, memory seats, sunroof work. The window regulators were all recently replaced.
Interior is nicer than my 300SD (all the wood is intact and shiny) no tears in the seats, headliner is nice and smooth
Engine runs smoothly (much smoother than a 5cyl)
Oil pressure looked good
No blowby
Transmission shifts smoothly
Just passed the tough Va inspection
CCU works diverting air to the right vents and altering the temperature from hot to outside temp
Has a power tilt wheel
ABS
Airbag


The Bad:
AC compressor does not engage even in 'def' mode. How much is a new compressor for this car? It is not a GM R4, but looks like a Sanyo or other Japanese compressor (small and aluminum)

The fuel return lines are leaking so badly I did not want to drive the car much. diesel is litteraly visibly seeping from all the lines and down the block. (easy fix)

ABS light comes on, tachometer stops working and ABS funtion cuts out. (easy fix?, ground issues? what could it be?)

The engine will not shut down with the key. (vacuum issue) I did not try to diagnose it, but after dealing with the vaccum switch in the dash of the 300SD I am hoping it is the valve in the IP even if that is a more expensive part

It has the #14 head, but running the car and driving it the temp never got above 85.

Green antifreeze!

Right rear door check is loose (you can hear it creaking when you open/close the door)

Outside temp gauge inoperable (I have one I pulled from a 560SEL) so no biggie.

The Ugly:

It has 289k on the clock!

Rear bumper had lost it's shine. Would the one from the '81 SD fit properly on a 1986 SDL?

Aluminum wheels have lost their clearcoat

Looked by the turbo and I could not tell if it had a trap-ox, did the federal 603 powered cars have that in '86?


The guy wants $2800 for this car. Do you think it is worth the money?
Looking under the hood I realized how much more complex the 603 is over the 617. Wow, electrical connections to the intake, IP,etc...

It drove nicely, shifted smoothly and drove well on a combo of local roads including gravel. I only got it up to 60 so I could not tell if it will run well at 75. It is not fast, but it has a virgin ALDA and will also probably need the turbo boosted to 13psi I am thinking it is probably set at 7~9 like the 617 was at the factory. Have people disabled the EGR/ALR on 603's like you can on the 617? Also does anybody know if the 300SD 14 inch wheels will fit properly on the 300SDL? I am asking because I just bought a set of Blizzaks for the 300SD and I would like to swap them over to the SDL if I buy it.

Thanks for reading a long post...

[LUVMBDiesels]

Any one?

Feel free to chime in

[daw_two]

If I lived closer, the car would already be sold. I would offer the seller $2300, just because you can't pay full price. If the front seats aren't split, then either they have been replaced, recovered, or the car has been garaged.

You did say no rust, right?

[sixto]

Originally Posted by LUVMBDiesels

The Bad:
AC compressor does not engage even in 'def' mode. How much is a new compressor for this car? It is not a GM R4, but looks like a Sanyo or other Japanese compressor (small and aluminum)

I think it's the same Nippondenso compressor used in all MBs from 86. The speed sensor at the back might make it a unique MB part.

Originally Posted by LUVMBDiesels

ABS light comes on, tachometer stops working and ABS funtion cuts out. (easy fix?, ground issues? what could it be?)

I'd start with the OVP relay fuse, OVP relay, voltage regulator...

If the tach isn't working because there's no signal from the flywheel sensor, cruise and AC compressor won't work either.

Originally Posted by LUVMBDiesels

The engine will not shut down with the key. (vacuum issue) I did not try to diagnose it, but after dealing with the vaccum switch in the dash of the 300SD I am hoping it is the valve in the IP even if that is a more expensive part

If it is the IP vacuum actuator, read gsxr's post on removing the ALDA without removing the intake manifold. The ALDA covers one of the screws that retains the vacuum actuator.

Originally Posted by LUVMBDiesels

Right rear door check is loose (you can hear it creaking when you open/close the door)

Maybe it just needs to be lubed.

Originally Posted by LUVMBDiesels

Looked by the turbo and I could not tell if it had a trap-ox, did the federal 603 powered cars have that in '86?

The pipe with aluminum heat shield is either 4" or 8" in diameter. 8" = trap.

Originally Posted by LUVMBDiesels

The guy wants $2800 for this car. Do you think it is worth the money?
Looking under the hood I realized how much more complex the 603 is over the 617. Wow, electrical connections to the intake, IP,etc...

Sounds like a good price. You can pay $7000 for an SDL in the same condition.

Does it come with maintenance records?

Originally Posted by LUVMBDiesels

It drove nicely, shifted smoothly and drove well on a combo of local roads including gravel. I only got it up to 60 so I could not tell if it will run well at 75. It is not fast, but it has a virgin ALDA and will also probably need the turbo boosted to 13psi I am thinking it is probably set at 7~9 like the 617 was at the factory. Have people disabled the EGR/ALR on 603's like you can on the 617? Also does anybody know if the 300SD 14 inch wheels will fit properly on the 300SDL? I am asking because I just bought a set of Blizzaks for the 300SD and I would like to swap them over to the SDL if I buy it.

Maybe you mean ARV? EGR and ARV can be disabled with no risk of the ECU shutting off the fun.

An SDL probably can't take an SD across an intersection but beyond that it should leave an SD in the dust.

Sixto
87 300D

[LUVMBDiesels]

Sixto,
Awesome post!

I am understanding that I am going to be a newbie with this car if I get it.

I saw a picture of a 603 out of the car on ebay and you can't miss the trap if it had one so I am sure it did not have one.

It is good to know that if the tach signal cuts out the compressor won't work. That could be the problem with the climate control. I did not bother to check the cruise control as i figured it just would not work. Also the streets I was driving on were not ones you could cruise for enough time to see if it worked. I did forget to check the locks so the vacuum system could have more problems than just shutting off the car.

So all in all it is a good deal? Even with almost 300,000 miles on it and the green antifreeze and #14 heads?

I will call the guy when he gets back to Va on SUnday and see if I could make a deal.

I already offered him $2300 because of ALL the work it needed and he would not take it. I will be lucky to get it for 2800.


Anybody need a 300SD for parts?

Thanks again!