Head gasket '85 300CD - PeachParts Mercedes-Benz Forum

Jorn · #1 12-23-2009, 03:23 AM

How much would a head gasket job cost for a 300CD? Is this something a home mechanic would be able to do?

vtmbz · #2 12-23-2009, 08:30 AM

I did a head gasket on my 2.2l. It was the first time I'd ever had a car engine apart. I followed the threads on this site, and the CD shop manual very very carefully. It took a long time, required a lot of undisturbed space, but in my case was successful. You have to be clean, meticulous, and not in a hurry if you dont know what youre doing. I wouldnt recommend it to butterfingers. It helps a lot to have someone around to inspect the parts and pieces for damage, it seems like us novices cant always tell whats broken and what isnt broken!
But what fun to hear that engine fire up afterwards.

junqueyardjim · #3 12-23-2009, 09:17 AM

Headgasket job should be very affordable to any "Hollywood" type people. If it comes to groceries or head gasket, better buy groceries and do the head gasket. It is simply a job of getting the head off, ( and all which that entails), remove and replace the gasket, and then re-installing the head. (and all which that entails). On most American "flatheads" of the past, it was a pretty simple job. The Mercedes diesel is much more complicated then that, and as the previous writer said, great care must be taken and follow the service manual explicitly if you want success. Some special heavy duty tools are needed such as half inch drive breaker bar, torque wrench and special "triple square socket to remove headbolts and an engine lft to remove and re-install the head. It is very heavy.

engatwork · #4 12-23-2009, 06:56 PM

If you have fair wrenching abilities you can probably do it. Read up on it, have the proper tools and take your time.

layback40 · #5 12-23-2009, 07:07 PM

jorn,
Unless you have some experience with working on engines, best you get a mech to do it for you. I dont know what the 'book time ' is for a head removal & gasket replacement, I am an engineer, not a motor mech. The last time I did one, I started mid morning and had the job done by the end of the day. I think a good mech should be able to do it in an afternoon if they know what they are doing. Chances are they will find other problems like valves that need reseating, the head needs resurfacing -planeing, etc. Maybe you should talk with who ever has been doing the maintenance on your car.

johnjzjz · #6 12-23-2009, 07:32 PM

not for a guy with out the real want to do as a first time major repair

you can help someone who has done it but i would re think if your not really mechanicallly inclined - jz

Cr from Texas · #7 12-25-2009, 12:17 PM

Since you asked the question, I'd say you're not even close to being ready to start the job. Study up on the task and then make your decision.

rooster6224 · #8 12-25-2009, 10:22 PM

There is absolutely no question in my mind that this job will be an expensive repair. I own a shop in Bryan, Texas (www.bcsauto.com). First question is why it needs the head gasket? Did it get hot? How many miles on the vehicle. In my shop when this problem surfaces I do the gasket, timing chain, rebuild head (around $400 alone off the car), tensioners, water pump, turbo drain seal, front main seal if it needs it, new crank pulley keys, pop test injectors, thermostat, ect... By the way how is the turbo? Does it need rebuilding also? To do this job right will be expensive unless you are willing to spend the time and money not just on parts but on tools. I am not saying you can not do it but it is a job that takes skill and time to do it right.

Diesel911 · #9 12-25-2009, 10:43 PM

rooster6224 is right.
There is a reason why the Head Gasket gave out. What ever caused the Head Gasket to go may have caused other damage; even if only the Cylinder Head is warped.

On the other hand you are not going to know if there is other problems untill you remove the Cylinder Head.
Except for preserving the timing when you remove the Camshaft Timing Gear (and never raotating the Engine after that) the rest of removing the Head and replacing it is just straight mechanical stuff; reading, understanding and following instructions.

Another, exception might be if the Cylinder head needs to be Milled the Pre-chamber protrusion will need to be adjusted with spacers.

Brian Carlton · #10 12-26-2009, 10:02 AM

Head gaskets are always dicey due to the many unknowns that will be encountered during the job. One can ignore many of the issues found and do a quick and dirty head gasket, but this doesn't make a whole lot of sense.

A mechanic is going to hit you for $1200. in parts and labor to do that job if he doesn't do any of the associated "while you are in there" issues that develop.

When I did the gasket on the SD, it took the better part of four months........working sporadically..........and sending the head out to Metric for a complete rework. The engine got a water pump, new starter, new downpipe, jet-hot exhaust manifold (which did not stand up BTW), adjusted wastegate............all while the head was away.

The total cost of everything ran to about $1500. including the $650 spent on the head (new exhaust valves, new prechambers.

I have to tell you that this engine still puts a smile on my face every time I start it. 20°F............glow till the light goes out...........turn the key without any pedal..........and it's instantly running at idle without the slightest hint of stumble or a miss. The engine has 210K on the clock.