Automobile inspection for the rest of us - PeachParts Mercedes-Benz Forum

iNeon · #1 08-15-2006, 11:29 AM

I was crawling under the car yesterday looking for provisions to adjust the transmission shifting(does a 240 even have a vacuum modulator?) and I decided to just look at everything.

When I grabbed the driveshaft, what I assumed was the center support had a bit of give in it, but I futzed around in there and it seems like there was a rubber bushing around the whole thing.

I guess what I am proposing is that those with more experience tell those of us with less what to look for whenever we are changing our oil. Whenever I am looking around and giving the car a once-over, I tend to just think "yep, that looks like a car part" and I know that isn't what I'm supposed to be doing!

Is it a dangerous thing for those of us with less of a clue how things are supposed to be underneath our cars to do our own inspections? I can tell when something is obviously broken, but I really want to learn enough to be able to have confidence in the car-- I feel like it is falling to bits and just can't be sure it's so roadworthy on my own.

My Father is semi-helpful, but he is of the "if it hasn't fallen off yet, it's still good" school of thought and that just isn't good enough for me-- Fall classes are about to begin again and I really need the car to be able to cope with city traffic!

SD Blue · #2 08-15-2006, 02:42 PM

The Haynes manual has a really good routine maintenance section. It does a pretty good job on the wear and tear areas and fluid checks.

Jim Anderson · #3 08-15-2006, 03:07 PM

...where bolts used to be, especially with a diesel, thay have a tendency to shake things loose.

BodhiBenz1987 · #4 08-15-2006, 03:21 PM

I don't know much, either, and have the same problem .. however, I find that I pick things up here and there as things go wrong, and not necessarily when something falls off. Sometimes it's just a matter of reading everything I can get my hands on, other times I actually ask my indy, and he is great in that respect. For example, when I wanted him to look at a crack in the subframe mount, he said the crack was not a problem, but explained to me what to look for in the areas surrounding it (e.g., to watch the rear diff mounts because they'll need replacing soon. My dad also has some knowledge of things like suspensions and can point things out. But I find just standing over the engine compartment or lying under the car for several minutes staring is a good way to learn. I'm not afraid to come in here and ask if I see something I don't understand or am concerned about ... sometime I end up asking about something really dumb, but nobody seems to mind, and I still end up learning.

iNeon · #5 08-15-2006, 03:31 PM

I'm with you Miss Bodhi!

I do know the general ins and outs, but I worry that a minimally mantained 1979 automobile may not be the best starting point, if that makes sense. I can tell when something doesn't feel right, but my baseline is an elderly person's carport car, so I don't know if that is the best benchmark.

I'll check for a Haynes manual, but aren't those the ones that NEVER have a picture of the assembly you're working on, but always one of a "similar" model that looks nothing like yours?

winmutt · #6 08-15-2006, 03:37 PM

Quote:

Originally Posted by Jim Anderson

...where bolts used to be, especially with a diesel, thay have a tendency to shake things loose.

Er or just missing accessories (mine has millions of holes).

BodhiBenz1987 · #7 08-15-2006, 04:45 PM

Quote:

Originally Posted by iNeon

I'll check for a Haynes manual, but aren't those the ones that NEVER have a picture of the assembly you're working on, but always one of a "similar" model that looks nothing like yours?

I'm not sure about the Haynes manual ... for my 124, there's the "E Class Owners Bible" which is pretty useful. I am also very lucky to have the FSM for the chassi and body ... huge book, my dad happened to have a copy that I found. It has VERY minimal descriptions of repairs (assumes the reader already knows basic things that I don't know), BUT lots of great pictures so I can get a sense of what is supposed to go where and what bits and pieces are supposed to look like. If you can get a FSM cheap from anywhere, I would think that might be very helpful, at least in just identifying a part and seeing if it looks like it's supposed to.

Another thing I've learned ... many things are bilateral. Look at both sides of the car. If a part looks different on one side than the other, it could be a sign that something is wrong. Like if the sway bar linkage is not there at all on one of the rear wheels ...

barry123400 · #8 08-16-2006, 08:33 AM

Just looking at things is not good enough. At a minumin get someone to show you how to check out front end components. It usually means prying on various components. Should be done once in awhile. We have compulsory once a year safety checks here and by and large I approve of them. Nothing good about loosing a tie rod end or ball joint at speed for example. Would probably put your whole week off. Also keep an eye out for rust developing on chasis structural support points and the extent of it. Use of a pointed awl to make sure it is not really bad for example does not hurt. This was one of the problems on earlier mercedes in rust prone areas of the country.

BodhiBenz1987 · #9 08-16-2006, 08:58 AM

[QUOTE=barry123400;1247733]Just looking at things is not good enough. [\QUOTE]

Just FYI, I was not trying to claim that just staring at the parts was a good way to safely inspect the car.

I was just pointing out to iNeon that for folks like us, it's a fun thing to do in spare time simply to get a better feel for the anatomy of the car. When it comes to safety and the integrity of the car, I don't trust myself at all ... have my indy look over it (he has a lift, obviously, too, which helps). He'll explain anything that's out of place or that I need to watch.

dannym · #10 08-16-2006, 08:59 AM

Quote:

Originally Posted by SD Blue

The Haynes manual has a really good routine maintenance section. It does a pretty good job on the wear and tear areas and fluid checks.

Right on. I use my Haynes manual a lot. It's perfect for the weekend diy'r.

Danny

Hatterasguy · #11 08-16-2006, 01:05 PM

Experiance is really the only solution. After working on these cars long enough you will learn what to look and listen for.

A very slight amount of slop if the drive shaft is probably ok. But there is a center support bearing there that does wear, and to much will cuase vibrations.

iNeon · #12 08-16-2006, 02:34 PM

There is no driveline vibration at all, i was mostly looking to set the vacuum on the transmission, but i couldnt find any provisions to do so!

Another question:

Why is there 3 stripes of paint that look like a rastafarian flag on the driveshaft? It is yellow, green and red, and it doesn't look fresh.

gatorblue92 · #13 08-17-2006, 12:30 AM

Quote:

Originally Posted by iNeon

There is no driveline vibration at all, i was mostly looking to set the vacuum on the transmission, but i couldnt find any provisions to do so!

Another question:

Why is there 3 stripes of paint that look like a rastafarian flag on the driveshaft? It is yellow, green and red, and it doesn't look fresh.

im not convinced that the early 240D had a vac controlled tranny... at least mine has no lines anywhere near the tranny and i also dont have a drain plug in my tranny pan... not sure if thats a 240D thing or just a very early 240D thing (mine was built in jan of 77 so im guessing it has some leftover parts from the w115) i also have the paint lines on my driveshaft... im guessing it is something from the factory maybe a check was done on the car during assembly