1985 300D Vacuum Leak Suggestions?
 

Since the weather is finally warm again I wanted to tackle a vacuum leak. I suspect I have one for the following reasons: 1) The door locks don't always want to work and 2) The car takes an extra 5-8 seconds to shut off after I pull the key out.

I've been reading a lot about vacuum leaks but I learn to fix things visually. I really don't know where to start in terms of what to fix. I'm assuming it can be as simple as replacing some hoses if I'm so lucky? Does anyone have a picture of where the main vacuum mechanism is and what lines are coming out of it? I think it's by my break fluid reservoir if my logic is correct. Also, how do I test if a vacuum exists or not? Do I need a pressure gauge?

I'm sorry if I sound like an idiot. I have to start somewhere!

Thanks in advance!
Brian

Brian


The vacuum pump is on the front of the engine with a vacuum hose going to the brake booster. (big black thing on firewall)

If you are going to do any work on your car you should get a manual to get an idea about some basics. Its available on CD for cheap or the "Haynes" one is OK. For tracking down vacuum leaks a Mitvac is really handy. Harbor Freight has them, $50.00+-

What car do you have? Guess I was assuming a W123

First thing I would try is shutting it down with the doors locked to see if it shuts down fast then.... that would/could tell you that one of the locks is leaking. Also check all the connections going through the firewall to make sure they are nice and tight. For working on the locks, if that's the problem, you don't really need a Mityvac; just a piece of hose that will fit over the lines so you can suck on them (sounds crude but it works). No manual is going to tell you what lines do what on the 85..... might show you the main line but that's about it.

If you think it's the locks I'll run you through where to get to the lines to figure out which lock it is if you want. Good luck!

Wow! Thanks for being so helpful. I'll check it tomorrow morning when it stops raining! I'll keep you posted.

Cheers!
Brian