Putting new piston rings in 240d - PeachParts Mercedes-Benz Forum

1997alex · #1 02-18-2017, 10:53 PM

So I just started doing this about 1 week ago and its going well but its hard finding time doing this after work. Ive been looking on this site trying to find a build or something along the lines of replacing the rings in a w115 240d but i had no luck. So I've decided that i would make a thread on how to replace the piston rings. Im not a certified mechanic and yes this may not be a perfect job but i am not trying to build a new engine just need to replace the rings. I have replaced rings in my 63 vw karmann ghia because it was smoking so i just ended up buying new rings and at the time i didnt have money so that was one of my options.... im 19yrs old by the way. But ive decided to invest some of my time and money on this engine so i can finally drive my benz. I know alot of you guys are thinking why not buy a good running engine from a wrecked car? Well ive already parted two w115, one had a blown head gasket and the other was sitting for a long time so water seemed to have gotten inside the cylinders and rust everything competely. Those examples lead me to believe that many people who have owned these cars think they can just run it and run it until something happens like a blown headgasket. So most likely other mercedes engines have been neglected and why risk buying another for 300 or 400 if eventually it may fail. Thats how i see it and i also want to learn more. Ive got an older brother who is a mechanic and an uncle who also is a mechanic so that should make this job alot easier. Anyhow thats enough about me lets get on to the engine.

I will be posting pictures soon of my progress...... it was running but it smoked alot blue and white because of bad head gasket and rings the compression read 300 first cylinder 200 second and third cylinder and 250 fourth cylinder. The head was sent out to get rebuilt a guy in monterey was really cool and he charged me 390 including parts and labor so ill take it there. My older brother has sent parts to him and has had no complaints what so ever. So ive got the head at the machine shop and now im gonna disassemble the block, remove the crank, rods, pistons, and degrease everything. Will keep updating with pictures and let you guys know what ive done to it i really want to get this done by the end of this month.

Diseasel300 · #2 02-18-2017, 11:35 PM

More power to you. So few people want to tear into their own cars anymore. A bit of sweat equity and you'll have a vehicle you can be proud of. Make sure you hone the cylinders when you have the pistons out. If there isn't a good crosshatching pattern your new rings will never seat/spin.