Parts Catalog Accessories Catalog Tech Info Tech Forums
 
  Search our site:    
 Cart  | Project List | Order Status | Help    


Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Diesel Discussion > Alternative Fuels

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 04-02-2009, 09:05 PM
Registered User
 
Join Date: Apr 2009
Posts: 2
Safe to drive? possible vacuum leak - 1979 300D on WVO

Hi there

First posting - urgent issue because I want to get home from work safely tonight! And you'll have to excuse me because I'm pretty ignorant about cars - the Merc is my partner's pet project with the WVO thing.

In brief:
1) Brakes became hard after 40 mins of driving this morning and slow to stop completely.

2) Door locks don't seem to be working too good.

3) Engine wouldn't stop running when I turned the key - could take keys out and it was still going.

4) Got one of my work colleagues to stop engine - he blocked air intake thing for about a minute, then car stopped when it was unblocked

So, checking on postings and other sites, I'm pretty sure we have a vacuum leak problem which my partner thinks he can fix okay, but I still have to get home tonight.

Couple of questions:

1) How safe is it going to be for me to drive it home? I'm a bit worried about the whole hard brake thing, so am intending to leave well before peak hour, give myself extra braking room but it's still a 45 min drive, downhill mostly, to get home with lots of traffic lights.

2) Will it start okay since we "suffocated" the engine to stop it?

3) Does the 1979 300D have the fuel pump safety off switch / lever I've read about and is this a better option than cutting off air to stop the engine if I have to do that again? Just thinking about damage to the engine long-term if I have to do it more than once tonight.

4) Given I know zero about cars, am I on the money with the vacuum leak idea or could it be something else?

Any help hugely appreciated.

Thanks heaps

Ripley
Reply With Quote
  #2  
Old 04-02-2009, 09:12 PM
Registered User
 
Join Date: Dec 2005
Location: Carson City, NV
Posts: 3,117
I am almost 100% certain you have a vacuum leak.

Yes, your car has an "engine stop" lever under the hood. It's located on the left side of the engine about even with the top of the valve cover and about 3/4 of the way to the rear. It should have a red sticker on it that says "Stop."

The car should still start and drive ok after being throttled to death.

I've driven my 240D with a bad vacuum leak and did not consider it unsafe. However, I have pretty strong legs and can get the car stopped easily with no power assist. Others have reported having problems trying to stop without power assist. That's really a question for you.

Other than the hard brake pedal, run-on, and lock issues, driving with a massive vacuum leak shouldn't hurt anything.
__________________
Buying cars as an investment is almost as bad as hookers and blow, but you get a small residual back from the car when you off load it.-AlbertaBeef from CVN

83 300D Turbo with manual conversion and H4 headlights 335,xxx miles
07 Kawasaki Ninja 650 28,xxx miles
Reply With Quote
  #3  
Old 04-02-2009, 10:00 PM
Registered User
 
Join Date: Dec 2006
Location: Sunrise, FL
Posts: 2,051
Quote:
Originally Posted by Skippy View Post
I am almost 100% certain you have a vacuum leak.

Yes, your car has an "engine stop" lever under the hood. It's located on the left side of the engine about even with the top of the valve cover and about 3/4 of the way to the rear. It should have a red sticker on it that says "Stop."

The car should still start and drive ok after being throttled to death.

I've driven my 240D with a bad vacuum leak and did not consider it unsafe. However, I have pretty strong legs and can get the car stopped easily with no power assist. Others have reported having problems trying to stop without power assist. That's really a question for you.

Other than the hard brake pedal, run-on, and lock issues, driving with a massive vacuum leak shouldn't hurt anything.
Yup, you got vacuum problems. Running the car will not hurt anything,
not being able to stop when some little kid chases his ball in the street.
If you are only driving highway/interstate that would be one thing.
city driving fugedaboudit,
pop the hood and try disconnecting and plugging EVERYTHING except
the main line between the pump(in the front of the motor} and the brake
booster behind the master cylinder, see if you got brakes, if so that will get you home......figure it out at dawns early light
__________________
81 Mercedes 300SD 289k.......SOLD
82 Mercedes 300CD 252k......slow ride

82 mercedes 300 SD...mi Unknown
83 Mercedes 300D ????ksniff..gone too
84 Mercedes 300D 148k........SOLD
85 Mercedes 300TD 386k and holding some one elses project
Reply With Quote
  #4  
Old 04-03-2009, 12:02 AM
Registered User
 
Join Date: Apr 2009
Posts: 2
Hi guys
Thanks for your help. Going to try for home tonight with both feet ready to stomp on the brake pedal. I've only got little legs, but they've got a bit behind them from chasing after / carrying kids! Luckily, can do the trip in a way that doesn't go past any residential areas and is all industry / highway which will avoid a lot of the risks. There's a guy about 10 mins away who might be able to take a look at it straightaway anyway. Can't find the stop switch - somebody took the sticker off, but will have another look. I gather it's only really small about an inch long? Besides which, I can do the air intake thing. Appreciate the help.
Cheers
Ripley
Reply With Quote
  #5  
Old 04-03-2009, 03:07 AM
ForcedInduction
Guest
 
Posts: n/a
Quote:
Originally Posted by Ripley View Post
1) How safe is it going to be for me to drive it home?
On WVO? It might get you home but it cuts the lifespan of the engine significantly. The safe thing to do is use Diesel.
Reply With Quote
  #6  
Old 04-03-2009, 07:47 AM
oldsinner111's Avatar
nearing 60,life is over f
 
Join Date: Nov 2008
Location: Elizabethton TN
Posts: 3,561
Use only 70% wvo with diesel mixed.This keeps your lifespan.
__________________
1983 300sd and 1999 s320 with mobil one atf both cars
.
Reply With Quote
  #7  
Old 04-03-2009, 07:50 AM
ForcedInduction
Guest
 
Posts: n/a
Use only 70% wvo with diesel mixed. This keeps your lifespan very short.
Reply With Quote
  #8  
Old 04-03-2009, 10:02 AM
Admiral-Third World Fleet
 
Join Date: Feb 2002
Location: Central FL
Posts: 3,065
I think yours is old enough to have a vacuum pump with a diaphragm in it. That could be your problem (hole in diaphragm)
__________________
80 300SD (129k mi) 82 240D stick (193k mi)77 240D auto - stick to be (153k mi) 85 380SL (145k mi) 89 BMW 535i 82 Diesel Rabbit Pickup (374k mi) 91 Jetta IDI Diesel (155k mi) 81 VW Rabbit Convertible Diesel 70 Triumph Spitfire Mk III (63kmi)66 Triumph TR4a IRS (90k mi)67 Ford F-100 (??)
Reply With Quote
Old 04-03-2009, 10:02 AM
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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -4. The time now is 12:18 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page