Help!! 1985 300ds turbo diesel engine removal - PeachParts Mercedes-Benz Forum

Mindseternal · #1 04-16-2016, 11:47 PM

I have a 1985 300ds turbo diesel and I need to remove the engine. I always work on my cars because I can't really afford to take them to a shop, but I've never removed an engine before, let alone a mercedes engine. I need to know what to do and in what order. If anyone could help that would be greatly appreciated. What I need to know is 1. how to unbolt the engine mounts (are they the allen head bolts that go through the rubber mounts?) 2. What do I need to remove, and how to remove it? (should I unbolt the transmission? or undo the driveline and how?)3. Do I need to remove anything off of the front of the engine? (The fan and shroud are already off) 4. do I need to remove fuel lines and Throttle linkage? And from where? 5 Remove the hoses from the radiator and oil cooler right? I know some stuff is obvious, But treat it like you are explaining it to someone who has never seen an engine before, so I don't accidentally miss anything small. Step by step Instructions are what I'm asking for. I know there are a lot of people out there like me who wouldn't mind helping If they could. If you could Include Pictures that would be really helpful. I know It is a lot to ask, but I'm just a broke college student who is dead in the water, and don't know what else to do. I have a 1985 300sd turbo diesel with a hole in the block, and a 1984 300ds turbo diesel that stopped running after I ran it out of fuel. I believe I can make one working engine out of the two, I just need to get the damn things out first. Thank you In advance for any help you can provide.

dkr · #2 04-17-2016, 12:28 AM

I seriously doubt you are going to make one engine out of the two.

It would be more realistic for you to pull an OM617 out of a junkyard car. At that point, you would have already learned how to pull it and in general, installation is the opposite of removal.

Dkr.

engatwork · #3 04-17-2016, 07:56 AM

Remove the throttle linkage starting at the firewall and that should be the only piece you have to remove.
Pull the engine/transmission together.
If you are going to remove the harmonic balancer loosen it before pulling engine.
The engine and transmission will need to be at a 45 degree angle to remove.

BirthdayBenz · #4 04-17-2016, 09:13 AM

I just did this about a month ago so on a 300D and 240D its fresh in my memory. Some things may be different on the SD.

1. Unbolt the engine mounts from beneath the car. These are hex head bolts (allen). Unbolt the engine shock mount from beneath. You may need an impact or some type of power driver as this will spin within the shock otherwise.

2. disconnect or remove:

battery
radiator
fan shroud
coolant hoses
fuel lines. mark where they go. route a hose between the two so fuel doesn't keep spilling out.
Air cleaner housing
Unbolt exhaust at back side of turbo
Throttle linkage at firewall bushing
All vacuum lines going to engine and trans. Make note of where they go.
wiring
unbolt power steering pump from engine and wire it out of the way. No need to remove the lines.
remove oil pressure feed to gauge. I removed mine from the cluster. I suppose you could remove it from the engine side if you wish.

Get under the car:

Mark your drive shaft where the two parts connect in case they separate.
Disconnect exhaust from transmission.
remove transmissions mount bolt. the one for the rubber, not the ones mounting it to the car.
remove grounding strap on driver side of transmission.
remove speedo cable from trans.
remove bolts from flex plate on driveshaft/transmission output shaft.
remove wiring from starter
remove wiring from alternator.

When you're ready to pull the motor and your car is elevated on jackstands, you can remove the bolts for the trans cross member. Support the trans with a floor jack so it doesn't fall when you remove the bolts. Use a prybar to help the flexdisk separate from either the drive shaft or trans side. On my 300D the drive shafts separated and I ended up pulling the whole thing out with the front dirve shaft attached. Your engine should come out at an angle.

One thing I didn't mention was AC. Its a pain. Mine wasn't working in the 240D and it wasn't charged so I disconnected the lines. When pulling the motor from the 300D, I wasnt sure what the situation was so I left the lines connected to the body and the compressor, removed the compressor from the engine and pried the lines out of the way when I removed the engine. Its far easier to remove the lines, but I wouldn't do it if you have working AC. It's also bad to vent refrigerant to the atmosphere, and should be evacuated properly.

I'm sure someone will chime in if there's something I've forgot or if there's something unique to the SD chassis.

BirthdayBenz · #5 04-17-2016, 09:28 AM

Things you'll likely want to buy and replace as part of this work.

Engine mounts - They're always bad.
Engine shocks - expensive some might consider it optional
Engine shock mounts (somehow these were still good on my 300D) - expensive
Transmission Mount - It's probably bad I've got a new one I'll ship you for $10
Rubber throttle linkage mount on firewall
Turbo drain grommet and o-rings - only if leaking also optional
Coolant
Oil and filter
Fuel filters - optional
Drive belts - optional

ROLLGUY · #6 04-17-2016, 11:00 AM

If you decide to leave the trans in the car (no need to remove it if it is working, and is staying in the car that will get the good engine), remove the three sets of bolts (six total) from the flex plate through the window in the bottom of the intermediate plate (rear of upper oil pan). Push the torque converter towards the rear of the car (an inch or less). Remove everything suggested in the above posts connected to the engine, and then the bolts holding the trans to the engine. Support the trans before separating the engine from it, and pull it from the engine bay. Be sure NOT to allow the torque converter to come out of the splines in the trans, or get stuck to the flex plate while removing the engine. If you do, it will leak out much fluid, and it will be tricky to get the splines and pump drive lined up again. However, now would be a good time to replace the front shaft seal in the trans, so removing and draining the converter (it can be drained before by removing the drain plug with 5mm) would be prudent. Just be sure to get the splines lined up and the converter in ALL THE WAY before mating the new engine to it. It is very easy to break the front pump or converter if things are not properly in place.

MagicBus · #7 04-17-2016, 01:35 PM

Your 1984 - is that a complete, otherwise driveable car?

You say it ran until you ran it out of fuel. If I were a betting man, I'd say that engine should run again in short time. If you got air into the fuel system (as one would do by running the tank dry), it can take a while to purge air from the system. Once you do, it should run with a fresh battery, providing there's nothing else wrong.

If I were you, I'd see if it were feasible to get the 1984 running and just drive that car.

vstech · #8 04-17-2016, 01:39 PM

If What is a 300Ds? A w123 or a W126?

If the s is a wagon, the head has a pump built in...

The two chassis have differences. The oil filter enclosure with the oil pressure connector, for one. The tach is different on the 85 from the 84... so the intermediate plate between block and transmission will need swapping... also the IP is different...

ROLLGUY · #9 04-17-2016, 02:00 PM

Quote:

Originally Posted by vstech

If What is a 300Ds? A w123 or a W126?

If the s is a wagon, the head has a pump built in...

The two chassis have differences. The oil filters, for one. The tach is different on the 85 from the 84... so the intermediate plate between block and transmission will need swapping... also the IP is different...

The oil filter is different? I believe ALL 616 & 617 from '78-85 (turbo and N/A) all take the same oil filter. If you are saying the oil filter stand, then yes, the stand is different in an SD than a D (I believe the steering box is in the way). As far as the IP, it should (or better yet "may") have the rack position sensor and ARV on both the '84 & '85. Both of these will not prevent either engine from fitting or running in either chassis, they are only for emission control. If both the '84 & '85 have the tach pickup on the intermediate plate (I believe both should), then the tach should work with either engine. Suffice it to say, the tach equipment (whatever that might be) needs to stay with the chassis that will get the good engine.

mach4 · #10 04-17-2016, 02:07 PM

Quote:

Originally Posted by Mindseternal

...I always work on my cars because I can't really afford to take them to a shop, but I've never removed an engine before, let alone a mercedes engine.....I'm just a broke college student who is dead in the water, and don't know what else to do.

The above statements suggest that maybe an old Mercedes is not the ideal car for you at this stage of your life. I'm also reminded of the old axiom that "there's nothing more expensive than a cheap Mercedes". While a Mercedes can be reliable and economical, they can also be huge time and money sinks.

Now I'm not trying to stick my nose where it doesn't belong, but I'd suggest it might be a good exercise to do a little cost-benefit analysis and see if a strategy to get rid of the MBs for now and getting a Toyota, Subaru, Honda or ?? would provide reliable transportation for school and more time for studies, work, dates and whatever else.

....plenty of time for a MB hobby down the road.

Just a thought without the benefit of context or priorities....

t walgamuth · #11 04-17-2016, 03:55 PM

Quote:

Originally Posted by mach4

The above statements suggest that maybe an old Mercedes is not the ideal car for you at this stage of your life. I'm also reminded of the old axiom that "there's nothing more expensive than a cheap Mercedes". While a Mercedes can be reliable and economical, they can also be huge time and money sinks.

Now I'm not trying to stick my nose where it doesn't belong, but I'd suggest it might be a good exercise to do a little cost-benefit analysis and see if a strategy to get rid of the MBs for now and getting a Toyota, Subaru, Honda or ?? would provide reliable transportation for school and more time for studies, work, dates and whatever else.

....plenty of time for a MB hobby down the road.

Just a thought without the benefit of context or priorities....

I was thinking this. I was going to say to buy a haynes repair manual or a mercedes factory manual. If you cannot afford the book likely you will not be financially able to follow this job through to fruition.

If the second car won't start after running out of fuel what is the problem? If running out of fuel is all that's wrong it should start right up with fuel in it.

chasinthesun · #12 04-17-2016, 04:45 PM

Its alot of work ,I know you dont want to hear alot of advice but its kind of asking "what would you do "kind of scenerio.I would start by asking why not look at the running car first ,if it ran out of fuel and wont start its most likley the tank screen ,the diesel injection pump is quite strong and can pull the junk up into the screen ,kind of like gummy gooo lieing at the lower surface of the tank. Pull the screen with a replacement fuel line and hose clamps at the ready ,the old line will probably be bad and not replacable.Ramps are your friend when working on these cars ,so locate a set and give it a go.You will need to aquire a large socket ,$20 at most northern tools.If you go for a motor pull you might look for someone who has all the equipment and tools and give you a deal if you help because your cost in tool renting and new tools you may buy will come out about the same .Maybe a fellow close Peachparts follower here can help you out ,worth a try.

Dan Stokes · #13 04-17-2016, 07:06 PM

Birthday Benz has given you a gold mine of info but I'd agree with the other old farts (I'm one too) who suggest that you back up and look at the old Benzes as a hobby and not so much as a mode of transportation. The guys have given lots of great info but I'd question if this is the right time in your life to have the kind of car that needs so much effort to keep the wheels spinning.

I'll agree that the one that died after running out of fuel is most likely the easiest to resurrect - follow the tips given by the guys. They can be a bit tricky to bleed the air out of the fuel system but it IS doable.

Dan

mach4 · #14 04-17-2016, 07:17 PM

You should fill out your profile too - if we knew where you were, it's possible someone local could come by and take a look...maybe lend some tools...or just lend some diagnostic help.

resto108 · #15 04-18-2016, 01:04 PM

The factory service manual tells you all you need to know in a step by step format. It's also free. The pictures can suck, but still... I'm constantly surprised by questions like this. How do we raise awareness of or access to the factory stuff?