Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 05-03-2003, 09:52 AM
DaveTrif
Guest
 
Posts: n/a
Question 300D Clanking noise after long drives

I've had my '84 300D for about a year and have run into a clanking noise coming from somewhere underneath the car, but only after long drives (about 2 hours or so). Other than that it runs great. It seems to clank at a faster rate when I am accelerating.
Does anyone have any thoughts on what the problem is? I know I haven't given much to go on. This is a great site, by the way, it's answered many nagging questions for me (usually i can find my answer using a search). Thanks.

Reply With Quote
  #2  
Old 05-03-2003, 10:03 AM
Registered User
 
Join Date: Oct 2002
Location: Toronto, Canada
Posts: 700
My best guess would be something with the exhaust. I noticed that my car after a long drive sometimes when idling will make a clanking sound too but it's the exhaust hitting the suspension in one place, it's badly welded but it dosn't bother me. On the other hand, my dads acclaim clunks like no tomorrow because the honey comb in the catalyctic converter is loose, the hotter the exhaust gets the stranger noises it makes. It's all I can think of, I would not say it can be engien related cause engine you will hear from the beginning to the end, so it is most likely something that changes shape a bit once heated up, like exhaust.

xp
Reply With Quote
  #3  
Old 05-04-2003, 09:01 AM
DaveTrif
Guest
 
Posts: n/a
Thanks XP. I plan on taking the car to have a few things looked at soon (A/C mainly) and i will have them take a better look at the exhaust. It looks to me like the rear portion of the exhaust is fairly new but the front portion is a little rusted. thanks for the advice....
Reply With Quote
  #4  
Old 05-04-2003, 12:17 PM
84300DT's Avatar
Senior Member
 
Join Date: Jan 2002
Location: Mass.
Posts: 2,219
davetrif-another new englander !! - could suggest besides the exhaust which could be a likely culprit they / you also check diff oil -excessive play in the diff, and 1/2 shafts.

btw,watch the diesel forum for the next n.england gtg!
__________________
1984 300D Turbo - 231k....totalled 11/30/07 RIP
Reply With Quote
  #5  
Old 05-04-2003, 03:12 PM
DaveTrif
Guest
 
Posts: n/a
Thanks. Now i have a new problem. On my way home today my brakes were very sluggish and the engine won't shut down right away. From what i've been reading here it must be some type of vacuum problem. Any suggestions?
Reply With Quote
  #6  
Old 05-04-2003, 03:31 PM
84300DT's Avatar
Senior Member
 
Join Date: Jan 2002
Location: Mass.
Posts: 2,219
make sure there is no leak or blockage in the brake booster line leading from the vaccuum pump on the front of the engine and also the 'tee' fittings in the line are open/clear. do a search on the diesel forum.. you will find a wealth of info on those subjects there.
__________________
1984 300D Turbo - 231k....totalled 11/30/07 RIP
Reply With Quote
  #7  
Old 05-04-2003, 03:34 PM
Registered Diesel Burner
 
Join Date: Aug 2001
Location: Northern Virginia
Posts: 2,911
The vacuum pump is pretty sturdy on the 82-85 300D cars. However, the check valves can gum up and stick, and there is one check valve on the output of the pump (that is, vacuum side) that is known for breaking or dislodging.

You can take the front cover off the vacuum pump once you pull off the fan. The fan comes off with four bolts. Inside, there are three round check valves about the size of a nickel that you can pop out and clean. On the output pipe, you might find pieces of the output check valve, like a spring and a plastic piece.

On my car, the plastic piece on the output check valve managed to get exactly lodged against one of the other check valves and blocked it off. It is now functioning fine without that output check valve.

Of course, before you tear into the vacuum pump, you really should take a vacuum reading with a gauge, and look for a broken or cracked vacuum line running from the vacuum pump to the brake vacuum assist unit.

Ken300D
__________________
--------------------------
1982 300D at 351K miles
1984 300SD at 217K miles
1987 300D at 370K miles
Reply With Quote
  #8  
Old 05-04-2003, 07:57 PM
DaveTrif
Guest
 
Posts: n/a
Thanks for all the info. I will be following up on it in the next couple of days. Funny after parking my car about an hour away when i had the brake problem, i went back to retrieve it and drive it as is. Not far into the return trip the brakes were normal again and when i shut it off it turned right off. But i will be checking the vacuum pump. thanks again

Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 11:27 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page