I am preparing to change the engine mounts on my 1982 240D as a close examination of the unit while it was failing to start using the starter revealed excessive engine motion and a completely failed driver side engine mount. This car runs nearly flawlessly, gets great mileage and uses a normal amount of oil, like a quart to a thousand or twelve hundred miles. It seems to have a few oil leaks too, but it does not smoke offensively, even at idle, has good torque, and keeps up on the highway on steep slopes. We just drove it from Plattsburg, NY to Albany last night and it pulled a two passenger/light load up the hills on the Northway (87) through the Adirondaks without straining at an even 65 mph. But it won't start consistently. Some times it will start ok, cold or hot, and then it will not start unless it gets a push. It starts immediately when you roll it a little and drop the clutch in second gear. The vehicle has 273,000 plus miles on it and my daughter uses it for daily transportation at college.

Since the starter is kind of picking up the motor instead of turning it over, I think the engine is turning to slowly on the compression stroke to start. Could be a kooky theory, but I will check it out. I am also replacing the starter as this weekend the unit went dead after a prolonged session heaving the motor around instead of starting it. I think with the motor properly restrained the starter will have a better chance of performing the function it was designed to perform instead of this circus act it was doing.

So, to get to the question, are there any special tools or tricks involved in changing the motor mounts? I have never attempted this before and am wondering if I need some special tools or wrenches. I have reasonable set of tools and two hydraulic jacks, so I was intending to unbolt the unit, lift the engine up with the jack(s) and remove and replace the mount, install the fasteners and call it a day. I am hoping someone out there has done this before and can tell me what the real process is like. Thanks, Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

Use the hydraulic jack with a 2x4 piece of wood on it. Raise the jack underneath the oil pan until it touches securely. Remove the bolts holding the engine mount on. Raise the jack until you can remove/replace the engine mount. Lower the engine and install/tighten the bolts holding the mount then move to the other side. I have done it on my 300D but not a 240D but there should not be any difference. I personally do not think it is going to resolve your hard start problem though.

__________________
Jim

Changing the motor mount sounds easy if there is no complication. Check out the following link for motor mounts:

http://www.peachparts.com/shopforum/showthread.php?threadid=13629&highlight=Sears

David

engatwork and be459,

Thanks for the help. Sounds like I will use a little grip compound from under the kitchen sink on the allen sockets in the screws. This forum is a great source of helpful information. While my knuckles will still get skinned and my fingernails loaded with some of the nastiest grease and dirt known to man, at least I will start the job with a clue as to how it is supposed to proceed. The old days of figuring out this stuff on the fly were fun, but it is much more relaxing to start the job armed with some "virtual" experience. Thanks again, Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

Just thought I would update you guys since you seemed interested enough to help with advice and pass me some virtual experience.

Well, the underside of the car was pretty nasty with oil and grime, so I got completely covered in tar like ooze. It came off, and so did the engine mount bolts and then the engine mounts. For the record, the next time (if ever) I try this, I will take the bolt to the strut coming off the engine off first, then jack the engine up on the driver's side, and remove that irritating little cover piece. That thing made getting the 6 mm allen wrench into the socket head capscrew on the engine side a nightmare. The other side came apart with no problems. Going back together was also no real challenge, once I had the geometry of the situation figured out.

I also managed to find the transmission mount, which was covered and packed solid with goop. That device essentially disintegrated with the strain of the hydraulic jack lifting the motor so that chunks of the rubber kind of extruded out and fell in my face. So I ordered another one from Fastlane today.

While under the vehicle I removed the starter after verifying it was dead. Once out, it was kind of loose. The unit is made of three cylindrical sections, the part that engages the ring gear on the flywheel, the center section that I expect houses the motor, and the end cap that you make the electrical connections too. These are not loose enough to fall apart, but they are also not tightly bound together, as they will rotate 5 or 10 degrees relative to each other. Has anyone seen this before?

I ordered a new one of these too, after talking to the local dealer who says MB only stocks the one for the 300D/SD and it fits on the 240D, from Fastlane today. I selected the one described as "heavy duty" which is only listed for the 300D turbo/300SD and 300CD vs. the "light duty" one for the 240D at FastLane. I called the Fastlane guys and got their confirmation that the unit should fit.

So, I cannot verify my theory on hard starting just yet, but I am still optimistic that a strong starter, and a properly restrained engine will make the difference. The car just has too much liveliness and strength to be worn out just yet. I will post the final results, whatever they are, when the job is done.

Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

engatwork and be459

Well, I put the new starter in and the Fastlane transmission mount was not the right one, a communication problem as there were two choices based on chassis number, I guess. I ordered the right one at the local dealer after studying his microfiche library.

The real point of this communication is to let everyone know the mounts and new starter fixed the hard start problem. The machine starts in less than five seconds now, and there is no drama. Just starts and runs smoothly as it should and used to do a while ago.

so, for the record, broken motor mounts can lead to damage to the starter, which can lead to difficulty starting one of these beasts. Have a good weekend, Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

Jim,

Job well done, Congradulation! But I do not get it: why a broken motor mount can damage the starter?

David

David,

I am not real sure exactly what the sequence of events was, but I think it goes something like the following:

When the mount was actually broke in half, I witnessed the engine trying to start using the starter, and it would lift about an inch or more on the driver's side mount and bang back down as the starter turned the engine over. I did not go over to the other side of the car and look to see where the starter might be going to see if it was hitting anything. There is an "L" shaped bracket on the forward side of the starter that is fastened to the block using 17mm nuts, and some rinky dink screws to the forward cap on the starter. These screws were broken off when I took the starter out, so I am guessing some of the jumping around caused the starter to either hit an adjacent component, or after a few months of this activity, it just fatigued the screws and they broke. When I got the starter out the three cylindrical modules it is made of were loose, meaning they would rotated and wiggle quite a bit, but they did not fall apart into three pieces.

It is entirely possible the mounts had nothing to do with the demise of the starter, but having witnessed the beating about the motor went through trying to start at the end, I am leaning toward either over loading the starter structure due to out of phase torque pulsations from the compression of the engine as it turns, and the lifting of the engine and then dropping it back onto the broken mount as the starter was turning. I did not notice any damage to the starter like dents or other deformation from hard contact with the other components residing under the hood, so I am not attributing the failure to hard contact. Then again, it could have been just old and ready to die. The unit I removed was a rebuilt starter, by the way, provided by Mercedes-Benz to the previous owner some time before 1991.

I think the two failures are related, but can not prove it with the data I have and do not feel like running an experiment by putting the broken mount back in and seeing how long it takes to break the new starter. If someone has a better explanation, I am all ears. The car likes its new pieces and is running great again. And thanks for the guidance when I started the job, as without that "virtual experience" I might have given up and junked it. Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)