I Need Help With An Engine Change!!! - PeachParts Mercedes-Benz Forum

bjenterprises · #1 11-19-2004, 12:53 AM

Hey everyone,
I am going to try to put another engine in my 1985 300sd. The first one overheated. I need to know if there are any special tools I will need, I have heard there are some strange allen keys that will be needed.

Is it okay to lift the engine by the tabs at the front and back. Someone told me they can break off.

DOES ANYONE HAVE A STEP BY STEP PROCEDURE FOR SWITCHING OUT THE MOTOR?

Should I remove the transmission with the engine?

When I have the thing appart what else should I do to make my future with this car easier?

Thanks for all the help.

Pete Burton · #2 11-19-2004, 07:57 AM

use the search, but the lifting tabs are just that, you lift the engine and trans out together. That's the only way I've done it, but I don't see why you couldn't do just the engine. You need an engine leveler or tilter to take both out together, preferably better than the one I have.

engatwork · #3 11-19-2004, 08:34 AM

I have found that it is way easier to take the engine/tranny out together. You will want a load leveler because the engine/tranny have to be close to a 45 degree angle to get them out of there.

boneheaddoctor · #4 11-19-2004, 08:41 AM

UM.....I am sure you thought about this already but don't use the old radiator...if it overheated you have an issue that needs to be addressed or you will do it again.

wheelguru · #5 11-19-2004, 12:36 PM

I have only done this once. I did not need any special tools. I agree with the engine and transmission coming out together, that is how I did it. Take the hood up to the full upright position, and put the car back on the ground before you pull it out, with the transmission dangling down in back, you have to raise the hoist up quite high to get the thing out of the engine compartment. Don't forget to unplug the wires out from the transmission, and make sure to disconnect the throttle at the firewall. have fun.

Pete Burton · #6 11-19-2004, 03:19 PM

there's lots of hints. I can think of only a few at a time. Disconnect starter wiring on body, leave wires on starter alone. Starting yesterday, soak the connection between the turbo outlet and exhaust pipe. Pipe can be held up and out of the way with a single bungee cord. Remove the single large bolt under the engine mount, not the top 2. Remove the radiator (of course) and put a thick sheet of cardboard against the condensor because you want to use every cm of room you have. Putting a small floor jack under the trans allows you to lower it somewhat to remove the neutral switch. Be real careful to get it "unlocked" before you pry it out. Take digital pictures. Heater tube can be disconnected at head side only and pulled through the firewall. You cannot be too careful about avoiding getting crud in trans cooler lines. If you swap, push a 1/4" polyethylene tube through it to make sure there is not chips lodged inside. Blowing air through is NOT sufficient.

1985 300SD Sady · #7 11-19-2004, 03:25 PM

On mine, I just took the engine out. This is the only way that I have done it, but now that I look back on it, it would have probably been easier to take both the engine and transmission out together. What really got me were the bolts holding the flywheel to the torque converter. Its not so much getting those bolts out, its getting them back in. Takes a lot of time, not very hard though. If you have any real specific questions, I would probably know them. Also, I didnt use a 'engine leveler' which is definatly a good idea.

Pete Burton · #8 11-19-2004, 03:44 PM

The engine leveler isn't necessary at all if you take out the engine alone. The engine/trans together CAN be taken out without a leveler, but it's rough on you and the car (I'll never do THAT again

). The leveler makes it easier, a good leveler (not mine) would make it easier still. The last time I added turnbuckle links from the leveler to the engine lift points, much better. Didn't even break a sweat, but I had a beer anyway in case I did.

#9 11-19-2004, 03:59 PM

I have removed the engine alone and the engine/trans assembly together. Easier to remove and reinstall the engine/trans assembly as one. Especially with the install. lI picked up a lift/leveler at Harbor tools cheap. Works ok.
Drain the trans and the torque convertor first. Much lighter that way and gives you the opportunity to change that old fluid and trans filter the easy way.
Get a Haynes - most basic tool yet.
There are a zillion bolts in there, take your time to get them all. Especially with the stuff mounted to the transmission, lines, wires, tubes, ...
I removed the radiator and cut a piece of plywood to protect the ac condensor. Worked well.
Hope you have a real good torque wrench. Lots of aluminum there, should all be have a torque wrench used, or risk accidental thread stripping.
Last note here, the motor mounts give everyone fits. There is an allen bolt accessed throught the engine cradle, it gets real stuck. I could not break it loose. Finally used an electric impact, it is not as strong as a pneumatic, and rattled on it until it would twist out. Then used anti sieze when bolting back in.

bjenterprises · #10 12-01-2004, 05:14 PM

Thanks for all the sugestions. Just spoke with Phil and have all the seals, new engine mounts, and tranny bushings on the way. Saturday is the big day, I have a few guys comming over to help me. I couldn't find a floor jack so I figured they will lift the car while I work on it

. Just kidding. I am going to put the rear wheels on oil ramps, and use floor jacks for the front. I hope everthing goes smoothly. I have two seprate mechanics who are going to oversee the whole ordeal, but they said that I need to learn how to do it.
Questions,
Do I access the allen bolts for the engine mounts from the top or from under the car?
I did purchase a new radiator, Thanks Bonehead.
To get the engine out, I lower the car back down and then tilt the engine out???? Doesn't seem like there will be enough room to tilt it far enough to angle it as such to pull it out.??
My last enigine only had 128 k when it overheated, do you think the water pump is still good????
Thanks all,
3 days and counting.

Pete Burton · #11 12-01-2004, 06:07 PM

The Allen bolts are a 8mm hex, attached from underneath. Better to do that than remove the ones above. You can do the entire job without raising the car (I've done it), but if it makes it easier to disconnect stuff at trans + exhaust, raise it. I would definitely have it on all 4 wheels when the engine/trans is removed. The lower things are, the safer and more stable they are. As you raise it, you will start to tilt it. Go slowly, make doubly sure everything is disconnected and make sure the trans doesn't suddenly drop its far end against the floor. 3 people is more than enough.

Pete Burton · #12 12-01-2004, 06:46 PM

the turnbuckles really helped. The cheapo engine tilter was a disappointment alone.

engatwork · #13 12-01-2004, 07:07 PM

Quote:

I am going to put the rear wheels on oil ramps, and use floor jacks for the front.

You will want to be able to turn the back tires when you roll the driveshaft around to remove the front flex disc. In addition, you will want a pneumatic ratchet to remove the flex disc fasteners. Speeds the job up alot. Don't forget to loosen the lock nut on the driveshaft to enable you to slide the front end back somewhat.

Also, I'll repeat Pete's suggestion of going slow. This is very important. Lift, stop, look and tilt - repeat till engine (when level) will clear the cross member above the radiator. Then you will want to roll the car back a little, level the engine a little and continue on until the engine is level enough to roll the car all the way out from under it. Don't try to roll the engine lift around until after you have lowered the engine back down close to the floor.

There are quiet a few other things that I can't remember just right now but you will come to them

.

bjenterprises · #14 12-01-2004, 11:08 PM

The engine came today. Man is this thing big! I don't think I will try lifiting it on my own. I had asked previously about the engine tabs becasue a guy I talked to said they sometime will break off letting the engine fall. I don't want to get this far and have an engine drop on the front of my car.
Are there any specific torques I need to worry about. I am going to pull the other engine out, are there any parts I should keep off this thing, any parts worth anything?
Thanks again, I will let you know how things go. I will try to do a step by step with photos, to help any future aspiring, "brainless" mechanics like myself.
thanks

Pete Burton · #15 12-01-2004, 11:21 PM

Quote:

Originally Posted by bjenterprises

The engine came today. Man is this thing big! I don't think I will try lifiting it on my own. I had asked previously about the engine tabs becasue a guy I talked to said they sometime will break off letting the engine fall. I don't want to get this far and have an engine drop on the front of my car.
Are there any specific torques I need to worry about. I am going to pull the other engine out, are there any parts I should keep off this thing, any parts worth anything?
Thanks again, I will let you know how things go. I will try to do a step by step with photos, to help any future aspiring, "brainless" mechanics like myself.
thanks

use the lifting tabs, that's exactly why and only why they are there. You should torque the transmission components properly. I would keep the whole engine if possible, I still have my spare. Turbo, head, injection pump, intake, alternator, PS pump, etc,all very useful for spares