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 01-17-2005, 11:34 PM
Registered User
 
Join Date: Sep 2004
Location: oakland, CA
Posts: 20
50-60 deg. F cold start failure

the symptoms of the last month or so:
('81 240D)

-hard to start, rough start in only mildly cold weather. it will usually start after 3-4 5-second cranks. i let the glow plugs heat for 40 seconds or so.
-starts fine when engine warm
-occasional loss of power, esp above 60mph.. not consistent
-a little oil getting into the air filter, apparently through the crankcase cover vent and also possibly through the air intake manifold?
-some oil and/or fuel visible near injector #1. possibly just small oil leak in crankcase cover seal.
-overall burns about a quart of oil per 15-20 gallons of fuel, highway driving.

i partially melted the rubber sleeve on the fuel tank filler neck w/biodiesel. been running B20-B100.

the glow plugs measure the correct resistance (all around .5 ohms). i also can't find any leaks in the fuel lines. all the hose clamps were tight.

any comments/tips or other ideas are most appreciated. this is what i plan to do/check:

-switch to mobil 1 synthetic 5w30. is that the correct grade? would 0w40 be better?
-check for fuel tank vent blockage: check for physical obstruction and check via tank cap..
-check battery, ground connection, terminals clean
-check glow plug relay fuse
-clean injectors by running on diesel purge or equivalent.
-check fuel filter at tank (the other two were recently replaced)


which of those would be most likely beneficial? please give me some input.. thanks

jeff

'81 240D
'78 volvo 240DL wagon
test drove: '05 CDi. this benz is a racecar!
want to build: VW bus w/ 1.9L TDI engine


Last edited by jeffl; 01-18-2005 at 12:30 AM.
Reply With Quote
  #2  
Old 01-17-2005, 11:41 PM
Banned
 
Join Date: May 2002
Location: Blue Point, NY
Posts: 25,396
Check for 12V at the glow plugs when you turn the key to position #2. The relay may appear to function, but the plugs are getting no juice if the fuse is compromised.

2 quarts of oil per 1000 miles is quite high. How many miles on the engine. What's it's overall condition? Compression?
Reply With Quote
  #3  
Old 01-17-2005, 11:51 PM
Registered User
 
Join Date: Sep 2004
Location: oakland, CA
Posts: 20
its got 155k miles. glow plugs are getting 11.5V each. overall condition is pretty good, was garaged its whole life. engine runs fine.. just recently i drove it 350 miles at 70 mph nonstop. it won't go faster than about 85-90 though, on flat terrain. i haven't check the compression, i'd like to, but have to buy the tools first.

Last edited by jeffl; 01-18-2005 at 12:37 AM.
Reply With Quote
  #4  
Old 01-18-2005, 12:03 AM
Palangi's Avatar
L' Résistance
 
Join Date: Dec 2000
Location: Republique de Banana
Posts: 3,496
A. Please describe exactly how you measured the glow plug resistance.

2. How long since the last valve adjustment?

III. What happens when you run on petro diesel?

D. Any custom plumbing for the biodiesel?
__________________
Palangi

2004 C240 Wagon 203.261 Baby Benz
2008 ML320 CDI Highway Cruiser
2006 Toyota Prius, Saving the Planet @ 48 mpg
2000 F-150, Destroying the Planet @ 20 mpg



TRUMP .......... WHITEHOUSE
HILLARY .........JAILHOUSE
BERNIE .......... NUTHOUSE
0BAMA .......... OUTHOUSE
Reply With Quote
  #5  
Old 01-18-2005, 12:27 AM
Registered User
 
Join Date: Sep 2004
Location: oakland, CA
Posts: 20
glow plug resistance was measured with a standard multi purpose voltage indicator, set to 200 ohms, with one end at the plugs (or at the terminals above the left front wheel well) and the other end on a common, the crankcase cover for example.

no idea about the valve adjustment, but i can try to find out.

no custom plumbing for the biodiesel (yet). what do you recommend, what kind of fuel lines, filters?
Reply With Quote
  #6  
Old 01-18-2005, 12:40 AM
Palangi's Avatar
L' Résistance
 
Join Date: Dec 2000
Location: Republique de Banana
Posts: 3,496
OK, what I was getting at was whether or not you had isolated the glow plugs before measuring, which it sounds like you did.

I would definitely check valve adjustment. A Haynes manual will guide you through that pretty well. Sounds like it may not have been done for a while. The valves will get too tight if not kept in adjustment.

From your other posts, it appears that it has not run right since you got it, is that more or less correct? Did the primer pump leakage get resolved?

You didn't comment on the petro diesel. You may want to switch back to petro diesel for a couple of tanks and see what happens, just to rule out any possible biofuel problems. You need to make sure it runs right on petrodiesel before you jump into biodiesel.
__________________
Palangi

2004 C240 Wagon 203.261 Baby Benz
2008 ML320 CDI Highway Cruiser
2006 Toyota Prius, Saving the Planet @ 48 mpg
2000 F-150, Destroying the Planet @ 20 mpg



TRUMP .......... WHITEHOUSE
HILLARY .........JAILHOUSE
BERNIE .......... NUTHOUSE
0BAMA .......... OUTHOUSE
Reply With Quote
  #7  
Old 01-18-2005, 02:47 AM
Registered User
 
Join Date: Sep 2004
Location: oakland, CA
Posts: 20
i ran it on petro diesel for about 3000 miles before introducing biodiesel. ran fine for another 2000 miles on bio.. still runs fine, just this starting problem.

for the valve adjustment, i could give it a try tommorow, assuming i can get the right kind of wrenches, and if you think that's probably the cause of the problem.. or should i try something else first?

as for the last thread about this car, yeah i just replaced the primer pump and it started right up.. as posted in that thread.


thanks for the replyin!

jeff
Reply With Quote
  #8  
Old 01-18-2005, 09:51 PM
Palangi's Avatar
L' Résistance
 
Join Date: Dec 2000
Location: Republique de Banana
Posts: 3,496
Even with tight valves it ought to start at 50 degrees, assuming good glow plugs, good battery and good starter. My gut feeling is that you have fuel system problems. Maybe air in the system, or maybe plugged filters, or maybe even a problem with the fuel itself. Will it start at all? If so, I would get some known good fuel in it and see how it does.
__________________
Palangi

2004 C240 Wagon 203.261 Baby Benz
2008 ML320 CDI Highway Cruiser
2006 Toyota Prius, Saving the Planet @ 48 mpg
2000 F-150, Destroying the Planet @ 20 mpg



TRUMP .......... WHITEHOUSE
HILLARY .........JAILHOUSE
BERNIE .......... NUTHOUSE
0BAMA .......... OUTHOUSE
Reply With Quote
  #9  
Old 01-19-2005, 04:55 AM
Registered User
 
Join Date: Sep 2004
Location: oakland, CA
Posts: 20
>> OK, what I was getting at was whether or not you had isolated the glow plugs before measuring, which it sounds like you did. <<

actually, your first guess turns out to be the right one: i pulled out the glow plugs and retested them, and found 3/4 to have around 15 ohms of resistance. having replaced them, she fired right up.

i don't exactly understand what i did wrong on testing them the first time.. maybe you
can explain the right way?

so thanks again.. i sure was happy when that thing fired so easily. drove home late at night singin casey jones.


j
Reply With Quote
  #10  
Old 01-19-2005, 08:08 AM
Registered User
 
Join Date: Dec 2002
Location: RI shore
Posts: 2,937
Quote:
Originally Posted by jeffl
>>
i don't exactly understand what i did wrong on testing them the first time.. maybe you
can explain the right way?

j
Next time, remove the cover from the glow plug relay, then unplug the connector that goes to the glow plugs. Measure resistance from each of the terminals on the connector to engine ground. This tests each glow plug, it's wire and connection. Also, check the glow plug fuse at the same time to make sure it's not cracked or excessively oxidized.
__________________
'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.
Reply With Quote
  #11  
Old 01-19-2005, 08:34 AM
boneheaddoctor's Avatar
Senior Benz fanatic
 
Join Date: May 2004
Location: Hells half acre (Great Falls, Virginia)
Posts: 16,007
50-60 degree no start is definately a glowplug issue.....my recently acquired parts car was pulled out of a field, had 2 year old diesel in it and it started within 2-3 seconds after a 30 second glow cycle in 18 degree weather.

Now thats better than my good car does............
__________________
Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
---------------------
Section 609 MVAC Certified
---------------------
"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche
Reply With Quote
  #12  
Old 01-19-2005, 08:39 AM
Registered User
 
Join Date: Dec 2002
Location: RI shore
Posts: 2,937
Quote:
Originally Posted by boneheaddoctor
50-60 degree no start is definately a glowplug issue.....my recently acquired parts car was pulled out of a field, had 2 year old diesel in it and it started within 2-3 seconds after a 30 second glow cycle in 18 degree weather.

Now thats better than my good car does............
did you pick up that 79SD someone was trying to GIVE away here on this forum? I hope so.
__________________
'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.
Reply With Quote
  #13  
Old 01-19-2005, 08:46 AM
pberku's Avatar
Registered User
 
Join Date: Oct 2003
Location: Montreal, Canada
Posts: 737
A quick comment on your oil selection. Mobil 1 5W-30, is not approved by Mercedes. Mobil 1 0W-40, and Mobil 1 15W-50 are.

Additionally, Mobil 1 0W40 is approved by Mercedes for year around use.

Phil
__________________
'95 E300 Diesel, 264,000 Miles. [Sold it]

Last edited by pberku; 01-19-2005 at 09:52 AM.
Reply With Quote
  #14  
Old 01-19-2005, 08:56 AM
boneheaddoctor's Avatar
Senior Benz fanatic
 
Join Date: May 2004
Location: Hells half acre (Great Falls, Virginia)
Posts: 16,007
Quote:
Originally Posted by Pete Burton
did you pick up that 79SD someone was trying to GIVE away here on this forum? I hope so.
Thats the one I am talking about........motor needs a little tlc..........as its leaking fuel like a sieve........but any diesel that starts that easy in cold weather with 2 year old fuel..........and likely to be summer fuel at that.....is a great engine.

__________________
Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
---------------------
Section 609 MVAC Certified
---------------------
"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche
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 06:51 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, 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