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 11-13-2011, 04:35 PM
Registered User
 
Join Date: Nov 2011
Posts: 30
Lurking noobster outed...

Hey guys, and gals, just acquired a 1986 300 SDL from Alantbird here on the board. He's in Belen, NM and my wife and I are snowbirds in the Mayhill, NM area, 120 some miles NE of El Paso (we have a 50 acre hobby farm with an on-site wood-fired brick oven pizza restaurant in SW Wisconsin. If anyone wants to work 4.5 months, drive cars on the twisties in the Mississippi River bluff country, let me know, place is for sale). Car runs great, we're at 7200 feet up the Sacramento Mountains and have a few questions on things that need a 'fixin'. It's 1400 miles back and forth, and the fuel mileage was why we bought the car. Our rust-free 1985 Jeep Grand Wagoneer was great for our dogs, but a bit 'spensive to run~!

First, and most important, the heat works only at idle. After searching, I find that the monovalve diaphram is the likely culprit. I've already tried the disconnection of the two-wire plug, no difference. The CCU 'seems' to be working, I can hear the air flow change from upper to lower when I turn the temp thingy, and all the pushbuttons work. So, on the right track?

Also, the car is hard starting when cold outside. I've plugged it in, and, presto, starts right up. However, in milder temps, say, 35 over night, and 50 during the day, it still starts hard cold. I can get it to start, but fuel over-loading creates quite the cloud! Does the car have to be plugged in even in the 35-40 degree overnight temps, have no choice? The ALDA have been disconnected, as well as the EGR.

The sunroof doesn't work, nor do the rear windows, but I have the plastic sliders on order, motors work. Here's a pic!


Reply With Quote
  #2  
Old 11-13-2011, 04:40 PM
aaa aaa is offline
Registered User
 
Join Date: Nov 2008
Posts: 1,075
Quote:
Originally Posted by Grenadiers View Post
First, and most important, the heat works only at idle. After searching, I find that the monovalve diaphram is the likely culprit. I've already tried the disconnection of the two-wire plug, no difference. The CCU 'seems' to be working, I can hear the air flow change from upper to lower when I turn the temp thingy, and all the pushbuttons work. So, on the right track?
Yep.
Quote:
Also, the car is hard starting when cold outside. I've plugged it in, and, presto, starts right up. However, in milder temps, say, 35 over night, and 50 during the day, it still starts hard cold. I can get it to start, but fuel over-loading creates quite the cloud! Does the car have to be plugged in even in the 35-40 degree overnight temps, have no choice? The ALDA have been disconnected, as well as the EGR.
Sounds like glowplugs.
Reply With Quote
  #3  
Old 11-13-2011, 05:12 PM
stcbenz83's Avatar
Mercedes Euro 240D
 
Join Date: Mar 2006
Location: Louisville, KY
Posts: 1,056
Second the glow plugs for sure...
__________________
1983 Euro 240D 277K
2016 Mazda 6
Coming Soon, 2013 Mercedes E350 Bluetec
Formers:
2012- Mazda 3
2007 Outlander- complete pile
1995 E300 Diesel 208K
2007 VW Passat 2.0T 63K SOLD
2003 Jaguar X-type 3.0 Sport Sold 04/11 w/88K
2009 Lexus RX350 9061 miles. Sold 04/09
2008 Mitsubishi Lancer GTS:Totaled Sept.,09 @ 24,000
2003 Infiniti I35 58K Sold
1984 300 turbo diesel 222K
Reply With Quote
  #4  
Old 11-13-2011, 05:30 PM
Registered User
 
Join Date: Jan 2007
Location: WA
Posts: 184
I have a 617 W126 300SD and on the drivers front fender well is a box with the wires from the glow plugs, I believe the same is true for your car. My brother had the same car as you different color. If you pull the top off the black box you will see that there is a multi pined connector with the wires going back to the glow plugs. If you pull the plug you can test the viablilty of the glow plugs using a volt ohm meter, either analog or digital to see how many ohms resistence each glow plug drawing. A new glow plug draws approximately 0.7 ohms (Bosch French GP's) new. In circuit you may have a different reading but it will tell you how many GP's are still working and how many are not working. The most definitive way to test a GP is to remove it and with heavy jumper cables carefully connect the Black wire to the silver body of the GP and the Red wire to the threaded end and watch the tip of the GP get red hot within a few seconds. Best of luck with the new car, this site has a wealth of information for you to learn.
__________________
Gary
OBK #37
Reply With Quote
  #5  
Old 11-13-2011, 05:41 PM
Registered User
 
Join Date: Nov 2011
Posts: 30
Hey all, thanks for the replies. The PO just informed me that he replaced all of the GPs last december. So, I'll check the fender well plug with my ohm meter just in case. dave
__________________
1986 Mercedes 300 SDL
1975 Mercedes 450 SL
1985 Porsche 911
1980 Porsche 924 Turbo
1981 Porsche 924 Turbo
1971 Jeep CJ5 Renegade II
1995 Jeep Wrangler lifted
2001 Ford F350 Diesel to find more junk
2004 Car Trailer, to haul junk that the truck finds.
1993 Damon Challenger, diesel pusher RV
1958 Pam - Loving wife that puts up with the above!
Reply With Quote
  #6  
Old 11-13-2011, 05:47 PM
Registered User
 
Join Date: Jan 2002
Posts: 18,350
Is the glow plug light working correctly? Check for voltage to the plugs also when the key is in the glow position.
__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Last edited by vstech; 11-13-2011 at 06:37 PM. Reason: sp
Reply With Quote
  #7  
Old 11-13-2011, 05:53 PM
Registered User
 
Join Date: Nov 2011
Posts: 30
I just today, fixed the non-operating speedo/odo with a gauge cluster bought on ebay. Combined the speedo that worked with a side-gear from the spare cluster for the odo. Now have odo and accurate speedo!

However, the glow plug light was not working when I bought the car, we just listened for the buzz to stop before we started the car. I noticed today with the cluster out, that the light bulb for the glow plug relay was missing. My guess it's attached to the one of the other light 'holes'. Will have to pull gauge cluster once again, and turn key on to see which is the correct light. thanks.

Oh, yeah, what does 'corking' mean?
__________________
1986 Mercedes 300 SDL
1975 Mercedes 450 SL
1985 Porsche 911
1980 Porsche 924 Turbo
1981 Porsche 924 Turbo
1971 Jeep CJ5 Renegade II
1995 Jeep Wrangler lifted
2001 Ford F350 Diesel to find more junk
2004 Car Trailer, to haul junk that the truck finds.
1993 Damon Challenger, diesel pusher RV
1958 Pam - Loving wife that puts up with the above!
Reply With Quote
  #8  
Old 11-13-2011, 06:03 PM
Registered User
 
Join Date: Jan 2002
Posts: 18,350
Should be 'working'.
__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13
Reply With Quote
  #9  
Old 11-13-2011, 06:35 PM
Registered User
 
Join Date: Jan 2007
Location: WA
Posts: 184
If you have not played with MB diesels before, you will find that not all Glow Plugs are good. What you want in your car are Bosch German or French made GP's other manufacturers GP's just do not hold up.
__________________
Gary
OBK #37
Reply With Quote
  #10  
Old 11-13-2011, 06:38 PM
vstech's Avatar
DD MOD, HVAC,MCP,Mac,GMAC
 
Join Date: Mar 2006
Location: Mount Holly, NC
Posts: 26,835
could be a GP relay fuse too.
get the cover off, and get the meter on each screw and hit the key. you should show 0 volts. if you read ANY voltage across the screws, the fuse is bad.
__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!
Reply With Quote
  #11  
Old 11-13-2011, 07:14 PM
aaa aaa is offline
Registered User
 
Join Date: Nov 2008
Posts: 1,075
Or it could be simply not waiting long enough. The buzz has nothing to do with how long you wait for the glowplugs.
Reply With Quote
  #12  
Old 11-13-2011, 08:25 PM
vstech's Avatar
DD MOD, HVAC,MCP,Mac,GMAC
 
Join Date: Mar 2006
Location: Mount Holly, NC
Posts: 26,835
yes, what aaa is saying is the buzz is just a seatbelt warning. the GP's stay on for up to 3 minutes, depending on the model controller.
1. buckle seat belt.
2. turn on key, and listen for the CLICK from the controller.
3. when the click repeats, the plugs have turned off. you can tell by the dome light brightening.
4. start the car, if it starts fast, you've found the issue you've been having.
__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!
Reply With Quote
  #13  
Old 11-13-2011, 09:04 PM
retmil46's Avatar
Registered User
 
Join Date: Jun 2006
Location: Mooresville, NC
Posts: 344
A plug-in digital voltmeter in the cigar lighter can give you a good indication if they're working or not - a healthy set of GP's on a 603 will yank the battery down to 11 volts or below on a cold morning. I don't try cranking over my present 87 300D until the GP's heat up enough that the battery voltage recovers up to around 11.5 volts.
__________________
Just say "NO" to Ethanol - Drive Diesel

Mitchell Oates
Mooresville, NC
'87 300D 212K miles
'87 300D 151K miles - R.I.P. 12/08
'05 Jeep Liberty CRD 67K miles
Grumpy Old Diesel Owners Club
Reply With Quote
  #14  
Old 11-13-2011, 10:25 PM
Registered User
 
Join Date: Sep 2004
Posts: 8,971
Quote:
Originally Posted by vstech View Post
the GP's stay on for up to 3 minutes, depending on the model controller.
If you know of a controller that runs the plugs for three minutes before start, please furnish the part number.
Reply With Quote
  #15  
Old 11-14-2011, 07:01 AM
ngarover's Avatar
Registered User
 
Join Date: Oct 2010
Location: Northern Georgia
Posts: 1,964
I'll second the GP fuse itself. Mine looked good, tested bad.. I was able to use a "modern" fuse from the local parts store to replace, works like a charm now.

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 04:06 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page